72 Commits

Author	SHA1	Message	Date
Andrew Kesterson	2242cfac9f	Unbreak CI: https submodule URLs, and three suites that assumed a display ... CI has never gone green in the retained run history, and every failure is the same 20-second death during checkout: six submodules -- SDL, SDL_image, SDL_mixer, SDL_ttf, jansson, semver -- were registered with git@github.com: SSH URLs, and the runner has no GitHub key. The https submodules (libccd, tg, clay, and the two starfort ones) clone fine in the same run. All six now use https, which is what every stanza added since already did; these are public upstream repositories nothing here pushes to, so SSH bought nothing. Second problem, waiting right behind the first: the character, sprite and tilemap suites were the only three of seventeen that never set the dummy video/audio/software-render hints, so on a headless runner they die in SDL_Init with "No available video device" before testing anything. They now set the same three hints the other fourteen suites set. (How this survived: every local run happens on a machine with a display, and CI never got far enough to run a test.) Pre-flighted locally against every job the workflow defines, headless with no driver variables in the environment, exactly as the runner would: Debug with -Werror and coverage builds clean and all 37 tests pass including the coverage fixtures; RelWithDebInfo with -Werror builds clean and the perf suites pass their budgets at full scale; doxygen Doxyfile exits 0 under FAIL_ON_WARNINGS; and the new ui suite runs under valgrind with zero errors and no leaks. Co-Authored-By: Claude Code (Claude Fable 5, claude-fable-5) <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01KzBDV2fqgnUAcqCKqKvc71	2026-08-02 13:39:17 -04:00
Andrew Kesterson	badaf570ab	Stop a stationary pointer from pinning the menu selection ... A pointer parked over a menu row re-claimed the selection on every frame's declaration, so keyboard navigation fought the mouse sixty times a second and lost -- press Up, and the hover put the selection straight back. Found by the UI demo's scripted tour: its mouse click leaves the pointer resting on the menu, and the Up keystroke that followed did nothing. Hover now moves the selection only on frames the pointer actually moved (or clicked), through a frame-latched motion edge beside the existing press edge. Parking the mouse claims nothing; moving it onto a row still selects, clicking still selects and activates. Regression test drives the exact sequence: click a row, move the selection away by keyboard, redeclare, and assert the stationary pointer stole nothing back. Co-Authored-By: Claude Code (Claude Fable 5, claude-fable-5) <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01KzBDV2fqgnUAcqCKqKvc71	2026-08-02 11:24:57 -04:00
Andrew Kesterson	0679d40ee4	Add the widget helpers: dialog, HUD label, and menu ... The other half of the hybrid decision: an application that wants a dialog box, a score counter or a main menu gets each in one call, without touching a CLAY() macro -- and an application that outgrows them still has clay's whole DSL, because the widgets are nothing but functions that declare the same elements between the same frame bracket. akgl_ui_dialog is the JRPG textbox in one line: bottom panel spanning the layout, AKGL_UI_DIALOG_HEIGHT tall, one-pixel border, wrapped text. The NULL style *is* the textbox palette -- near-black fill, parchment edge and ink, 8px padding -- deliberately, so the widget and the 125-line hand-rolled panel it stands beside in the comparison chapter produce the same picture. Showing and hiding is the frame's business: call it while somebody is talking, don't while nobody is; a declarative frame is the visible flag. akgl_ui_label pins a fit-sized text chip to a corner or the centre, inset by the style's padding. akgl_ui_menu declares a centred vertical menu from a caller-owned struct (no heap layer: it owns no texture, no font, no registry entry), with the selected row drawn inverted, hover moving the selection and the frame-latched press edge activating it. akgl_ui_menu_handle_event drives the same struct from Up/Down/Return and D-pad/South with wrapping, slotting into the event chain after akgl_ui_handle_event; routing events to a menu is the application's focus model, stated rather than invented. Tests cover the dialog's geometry and palette by pixel, label anchoring by quadrant, menu validation, the inverted highlight, keyboard and gamepad wrap/activate/pass-through, and the full two-frame mouse protocol -- click aimed at the second row's real box via Clay_GetElementData, seen by the next frame's declaration as selection plus activation. Co-Authored-By: Claude Code (Claude Fable 5, claude-fable-5) <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01KzBDV2fqgnUAcqCKqKvc71	2026-08-02 11:17:32 -04:00
Andrew Kesterson	566b870a5c	Feed the mouse to the UI and tell the host which events it consumed ... akgl_ui_handle_event is the mouse half of the input story -- keyboard and gamepad stay with the control maps, because keyboard focus is something an application declares rather than something a pointer position implies. It handles motion, left-button presses and releases, the wheel and window resizes; everything else, and everything while the subsystem is inert, reports consumed=false and succeeds, the same pass-everything contract akgl_controller_handle_event already has. The documented call order is UI first, control maps second, skipping on consumed. A press, release or wheel is consumed when the pointer is over any UI element. The hit test asks clay against the layout the previous frame retained -- this frame's does not exist while events are polled, and one frame of staleness is the standard model's accepted cost -- with clay's internal full-screen Clay__RootContainer excluded, because being inside the window is not being over the interface (unexcluded, every click anywhere was consumed; the test that pins this caught it). Pointer state is fed to clay per event, as clay documents; the press edge is latched once per frame_begin for the widgets to come, rather than trusting Clay_PointerData's per-SetPointerState edge, which advances per mouse event. frame_begin also drives Clay_UpdateScrollContainers from the accumulated wheel (32 pixels per notch) and a wall-clock dt. Tests pin the whole contract: pass-through before init, no consumption before any layout exists, press/release inside vs beside a panel, right button ignored, motion never consumed, wheel consumed only over the UI, resize reaching the layout engine, and key events left alone. Co-Authored-By: Claude Code (Claude Fable 5, claude-fable-5) <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01KzBDV2fqgnUAcqCKqKvc71	2026-08-02 11:10:35 -04:00
Andrew Kesterson	3b3bfcbe10	Render clay layouts: fonts, text measurement, executor and the frame bracket ... The UI subsystem now draws. akgl_ui_frame_begin/frame_end bracket one frame's CLAY() declarations: begin clears the error stash and starts the clay layout, end computes it and walks the render commands through a backend -- RECTANGLE as (rounded) fills, BORDER as radius-shortened edge fills plus corner arcs, TEXT through akgl_text_rendertextat one wrapped line per command, IMAGE as an akgl_Sprite's first frame stretched to the bounding box, and the SCISSOR pair through akgl_draw_set_clip, cleared again on any exit so a failed frame cannot leave the world clipped. akgl_ui_font_register maps registry font names onto clay's uint16_t fontIds. The table keeps the *name* and resolves it per use -- fonts are not reference counted, and a cached TTF_Font* would dangle where a name reports "gone" honestly. Clay_TextElementConfig.fontSize is deliberately ignored: libakgl bakes the size into the handle at load, so one face at two sizes is two ids. The measure bridge passes clay's non-NUL-terminated slices straight to SDL_ttf's explicit-length TTF_GetStringSize -- no copy, no scratch. Its signature has no error channel, so failures report zero-by-zero and stash a message that frame_end raises, the same route clay's own void error handler uses; layout errors take precedence over drawing and one bad frame leaves the next one clean. Tests drive real CLAY() layouts through the software renderer and read pixels back: fill placement, border edges with an empty middle, a child clipped by its container, text landing in its colour, slice-vs-whole measurement agreement, fontId table dedupe/refusal/exhaustion, and the bracket's begin/begin, end-without-begin and failure-recovery contracts. Co-Authored-By: Claude Code (Claude Fable 5, claude-fable-5) <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01KzBDV2fqgnUAcqCKqKvc71	2026-08-02 11:06:27 -04:00
Andrew Kesterson	064e6569e8	Add rounded-rect fill, arc stroke and clip-rect drawing primitives ... The UI subsystem's render executor needs all three -- clay emits rectangles with corner radii, per-side borders, and scissor commands -- but they earn their place in draw.h on the same terms as everything else there: a rounded panel, a ring gauge and a clipped viewport are things a game wants with or without a layout engine. akgl_draw_filled_rounded_rect decomposes into three band fills plus four quarter-circle triangle fans through SDL_RenderGeometry, with the radius clamped to half the shorter side. akgl_draw_arc strokes between an outer and inner radius as one triangle strip, stepping in proportion to the swept angle under a fixed vertex cap -- no VLAs, unlike clay's own SDL3 reference renderer. akgl_draw_set_clip wraps SDL_SetRenderClipRect and is the one draw entry point where a NULL rectangle is legal, because that is how a clip is cleared. Pixel-readback tests cover the corner geometry (inside the arc filled, outside it untouched), the radius clamp, the zero-radius fall-through, ring and quarter-arc coverage at mid-stroke, sweep bounds, and clip set/clear round trips. Co-Authored-By: Claude Code (Claude Fable 5, claude-fable-5) <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01KzBDV2fqgnUAcqCKqKvc71	2026-08-02 10:57:23 -04:00
Andrew Kesterson	b7ff54b09f	Vendor clay and bring the UI subsystem up: arena, lifecycle, status band ... clay v0.14 (deps/clay, zlib licence) supplies the layout engine for the new akgl_ui subsystem. Sources-listed rather than add_subdirectory()'d, on the semver/libccd precedent: clay's CMakeLists declares no library target, builds its examples by default, and requires CMake 3.27 against this project's 3.10. src/ui_clay.c is the one CLAY_IMPLEMENTATION translation unit, compiled -w on the vendored-code terms but with clay's symbols deliberately exported -- consumers' CLAY() macros resolve against libakgl.so, and akgl/ui.h warns them never to link a second clay. The subsystem is runtime-optional the way collision is: always compiled in, inert until akgl_ui_init(), which bounds clay to the overridable AKGL_UI_* ceilings, checks Clay_MinMemorySize() against a static BSS arena (no malloc), and refuses with both numbers in the message when it does not fit. Measured: 812544 bytes at the default 1024 elements / 4096 measured words, against a 1 MiB arena. clay's void-callback layout errors are logged as they happen and the first is stashed for the error protocol to raise later. AKGL_ERR_UI joins the status band before AKGL_ERR_LIMIT, named in akgl_error_init. New `ui` test suite covers validation, the init/shutdown lifecycle, and arena exhaustion via the akgl_ui_arena_limit test hook (same contract as akgl_ccd_arena_set_limit). clay.h is installed beside semver.h, its licence beside libccd's, and the headers suite proves akgl/ui.h self-contained -- clay.h compiles clean under -Wall. Co-Authored-By: Claude Code (Claude Fable 5, claude-fable-5) <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01KzBDV2fqgnUAcqCKqKvc71	2026-08-02 10:53:11 -04:00
Andrew Kesterson	6553da812c	Rewrite both tutorials as tutorials ... They read as design commentary: why a choice was made, what the previous state of the project was, which library defect a line works around. That is useful to somebody who already knows the library and useless to somebody trying to build a game, which is who a tutorial is for. Both chapters now open with a screenshot of what the reader is building and a numbered list of the steps to get there, and each step is its own section: what you are trying to achieve, the code that achieves it, and the two or three things about that code that are easy to get wrong. Chapter 20 starts from first principles -- what a sprite, a character, an actor and a tilemap are, and the four error macros -- and chapter 21 assumes it and covers what a top-down game adds. Where a line exists because of a defect, the line comes first and the defect comes after it, with a pointer to the TODO entry that will remove the need. A reader who is copying code should not have to read an apology before they can use it. The library's own history is gone from both. That belongs in the design chapters and in git. Two new docs_examples setups stage the tutorials' own art, so the sprite and character files a reader is shown are loaded exactly as printed rather than through a generic fixture. `json excerpt=` is new for the same reason: a Tiled object is now quoted out of the real map instead of being retyped. Excerpts across docs/ go from 91 to 137. Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01KzBDV2fqgnUAcqCKqKvc71	2026-08-02 08:51:39 -04:00
Andrew Kesterson	4e32328681	Remove the corner helpers akgl_collide_rectangles no longer uses ... akgl_rectangle_points, akgl_collide_point_rectangle, akgl_Point and akgl_RectanglePoints go. They were the intermediate form of an implementation that changed: akgl_collide_rectangles was eight corner-containment tests built on them, and it has been four span comparisons since the cross-case fix. Nothing outside tests/ called either function, and a point-in-rectangle test is four comparisons a caller can write without a struct conversion in front of them. akgl_collide_rectangles stays. It has two correct callers in the sidescroller asking a game-level overlap question -- a coin, a hazard, from an updatefunc -- where a bool is the whole answer and a proxy plus a narrowphase call would be computing a normal nothing reads. TODO.md records the split rather than leaving it to be rediscovered. Public API removal, so 194 exported akgl_ symbols against 196, and the manual's counts move with them. The perf suite loses its rectangle_points row; the all-pairs sweep stays as the control it is now labelled, and PERFORMANCE.md says what 0.8.0 measured against it -- 188.5 us for 32,640 pairs at 256 actors, where a whole step with collision attached is 54.1 us doing strictly more. Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01KzBDV2fqgnUAcqCKqKvc71	2026-08-02 08:09:42 -04:00
Andrew Kesterson	3a6569e384	Build the shape before spawning a proxy from it ... test_reset_and_empty called spawn() with an uninitialized stack akgl_CollisionShape and built it on the next line. akgl_collision_proxy_initialize copies the shape, so grid_insert read uninitialized half-extents to work out which cells to file the proxy under -- eighteen findings inside grid_cellrect, and the test still passed because the proxy_sync two lines later overwrote all of it. Found by scripts/memcheck.sh, which is the only thing that could have found it: the assertion it makes is about the query afterwards, and the query answers correctly either way. Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01KzBDV2fqgnUAcqCKqKvc71	2026-08-02 08:01:17 -04:00
Andrew Kesterson	986c80d0ec	Bump to 0.8.0, close Target 12, and record what is still missing ... Collision changed the collide slot's signature and grew four public structs, so this is an ABI break and the soname moves to libakgl.so.0.8. The manual's counts move with it: 195 functions across 23 headers, 183 of which return an error context. Target 12 -- "collision for 256 actors under 2 ms without the caller writing a broad phase" -- is met. A new benchmark times the whole step with a world attached, which is the number the target is actually about rather than a narrowphase call in isolation: 15.4 us at 64 actors, and 54.1 us at 256 in a purpose-built -DAKGL_MAX_HEAP_ACTOR=256 configuration. Over that 4x range the step grew 3.5x while the all-pairs control grew 15.6x, which is the n-squared the index exists to avoid. Plan item 7 is rewritten to record what shipped and why both partitioners exist; the Construct and Phaser citations stay. Three new TODO entries. Actor rotation, scoped to the five places it touches and the one place it does not -- collision_support is written so rotating `dir` in and the answer back is the whole narrowphase change, and rotational *response* is explicitly a different piece of work. The swept narrowphase FLAG_BULLET reserves, with the tunnelling arithmetic written out so a game can check its own numbers against 1280 px/s. And the ccd arena being single-threaded and sized by measurement at 7,264 bytes per GJK/EPA box pair. Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01KzBDV2fqgnUAcqCKqKvc71	2026-08-02 07:53:30 -04:00
Andrew Kesterson	490e62dbbf	Delete the sidescroller's collision, and let the library do it ... collision.c was 383 lines that re-implemented akgl_physics_simulate's own arithmetic, because movementlogicfunc runs before gravity, drag and the move and so had to predict where the actor would end up. The whole file goes. What replaces it is three lines in main.c, a shape on the player and the blob, and a `collidable` property on the map's terrain layer -- which also retires SS_TERRAIN_LAYER_ID, a compiled-in layer id that broke whenever somebody reordered layers in Tiled. grounded stays a probe rather than becoming a contact test. A contact says something pushed back this step; grounded asks whether there is a floor to push off, and that stays true through the frame after landing. The blob keeps its own wall and ledge probes for the same reason: the resolver does not say which side of the blob it was pushed from, and says nothing at all about a floor that is missing. The summary line now carries the player's resting position, because exiting 0 was not evidence that collision ran. It reports 136.0,160.0 grounded after 240 autoplay frames -- feet at y=192, flush on the surface of terrain row 12. The tutorial's collision section is rewritten around the library's, keeping the quarter-of-a-pixel story as what a predicting resolver costs. The docs harness learns `json excerpt=`, so the map property the chapter quotes is checked against the map. Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01KzBDV2fqgnUAcqCKqKvc71	2026-08-02 07:35:08 -04:00
Andrew Kesterson	fcad2822a9	Measure collision, and say which numbers moved for what reason ... Seven new benchmark rows, budgets set from a measured full-scale run rather than guessed, and the three existing rows the work moved re-recorded from that same run. The all-pairs sweep stays and is relabelled `control:` -- it is the cost a caller paid before the library had a broad phase, measured on the same machine in the same run, which is the only honest way to read a reduction. What the numbers say: - The box fast path is two to seven times cheaper than the general solver, and the disjoint case is cheaper still because the proxies' bounds reject it before any shape arithmetic runs. 9 to 20 ns is what a tile game actually pays. - The grid beats the tree by 2.6x on the same population, which is the argument for the default measured here rather than cited from another engine. The tree also rebuilds on every move and that is not in its row, so a moving scene is worse than 2.6x. - A grid `move` that changes nothing is 11.5 ns. That is the incremental claim in one number. Two rows moved on a backend with **no collision world attached**, so no collision code runs in either, and the commit says so rather than letting the feature take credit: - akgl_Actor grew from 415 to 464 bytes -- a 40-byte shape, an override flag and a proxy pointer. The step sweeps the whole pool, so that is about 3 KB more working set per frame. The empty-pool row is unchanged at 58.7 ns, which is what identifies the cost as per live actor rather than per slot. - Reaching the collision check through CATCH cost more than the check. PASS and CATCH call akerr_valid_error_address, which walks AKERR_ARRAY_ERROR, so an early-returning function is not free when it is reached through one. The no-collision path now routes around the machinery entirely, which took the 64-actor sweep from 2,018.7 ns back to 1,588.5. AGENTS.md records that lesson for writing benchmarks; this is the same thing in production code. The remainder is the struct, and it is paid whether or not a game uses collision. Co-Authored-By: Claude Code <noreply@anthropic.com> Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>	2026-08-02 07:13:53 -04:00
Andrew Kesterson	cf930f68bb	Add a second partitioner, so the vtable is a seam and not a decoration ... A binary space partition on libakstdlib's tree links and lists, registered in the factory as "bsp". It runs the same assertions the grid does, because tests/partition.c is a table over partitioners and adding a row is all it takes to be held to the contract. **Use the grid.** This is here to prove the vtable works and to have something to measure the grid against, and the file says so at the top. It rebuilds whenever the proxy set changes, which is the shape PERFORMANCE.md records Phaser using and capping out around five thousand bodies. It would earn its place in a world with wildly non-uniform object sizes, or one larger than the grid's fixed cell array covers. The difference is visible in the code rather than buried in a benchmark: the grid's `move` compares four integers and returns when a proxy has not left its cells, and this one marks the whole partition stale. The incremental-move assertion in the suite is therefore grid-only, and says why. aksl_tree_iterate is not used, and the file carries the three reasons so the next reader does not rediscover them: it is a complete traversal whose only control signal stops the entire walk, so there is no way to prune a subtree -- which is the only operation a spatial query is made of; it carries no per-node context, and a pruning descent needs each node's bounds and plane; and its breadth-first modes allocate, while only the depth-first ones are malloc-free and those are the ones without pruning. aksl_tree_insert is unusable for a different reason again: it is a comparator-ordered BST, and a spatial insert has to compare a leaf against a plane, which aksl_TreeCompareFunc cannot express. What is used is the link structure and the lists, neither of which allocates, which is why they fit here at all. The descent is an explicit stack rather than recursion, so the depth bound is an array bound the compiler can see -- this library already has one documented way to blow the C stack and does not need a second. Split planes are the median of the item centres on the longer axis, not the spatial midpoint: actors in a tile game cluster on the floor, and a midpoint split gives one empty child and one full one for several levels running. A split that separates nothing degrades the node to a leaf rather than recursing forever on the same set. Co-Authored-By: Claude Code <noreply@anthropic.com> Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>	2026-08-02 07:08:54 -04:00
Andrew Kesterson	5e213061af	Call collide from the simulation, after the move rather than before it ... The collide slot has existed unused since the backend was written. It is wired in now, and its signature changes from (self, a1, a2) to (self, actor, dt): the old shape had nowhere to put a normal, a depth, or a piece of map geometry, and no answer to which of the two actors it was supposed to be resolving. **Resolution runs after `move`.** That is the decision everything else follows from. A resolver called from movementlogicfunc runs before gravity, drag and the move, so it has to predict where the actor will end up -- which means re-implementing the integrator's arithmetic in the game, and being wrong whenever the integrator changes. examples/sidescroller/collision.c carries forty lines of exactly that, and says so. Only `move` is subdivided. Gravity, drag, the thrust integration and the speed ellipse all still run once against the whole dt, and sum(subdt) is dt, so an actor with nothing to collide with takes one sub-step of exactly dt -- `dt/1.0f` is dt exactly in IEEE-754 -- and follows the arithmetic path it always did. That is what lets the integrator stay untouched and every recorded physics number stay valid, and tests/physics.c and tests/physics_sim.c pass unchanged with no world attached. Collision is opt-in. A backend with no collision world costs one comparison per actor per step and does nothing else. Also here: - `self->gravity` was never null-checked and is dereferenced unconditionally, so a hand-built backend with only `move` filled in crashed rather than reporting. - Children are re-snapped in a post-pass, gated on collision being on. The in-loop snap uses whatever position the parent had when the child's slot came up in pool order, which is already sometimes a frame stale; that was harmless while a parent only moved by v*dt and is not once a parent can be pushed out of a wall mid-step. - tests/physics.c's deliberate tripwire has been visited. It asserted that arcade collide always raised AKERR_API, with a comment saying it existed so that implementing collision would have to come back here. What replaces it asserts the opt-in contract instead. - physics_sim.c's hard-coded "%d of 7 simulations" is derived now. A literal goes stale the first time somebody adds a simulation, which is this commit. Three new whole-motion simulations, and the third took two attempts to make honest: - Landing and resting: 0.0000 px of drift over 120 steps after settling. - Walking after landing: 107 px in a second, which is the symptom a player sees when a resting actor is caught on the ground it is standing on. - A fast fall not tunnelling. The first version used gravity, so the step size grew every frame and the actor happened to land *inside* the floor rather than stepping over it -- it passed with sub-stepping disabled and proved nothing. It uses a constant 1200 px/s now, so every step is exactly 60 pixels against a 32-pixel window in which an overlap exists, and the samples miss it cleanly. With sub-stepping the actor stops at y=288; without it, y=1300. Co-Authored-By: Claude Code <noreply@anthropic.com> Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>	2026-08-02 07:05:09 -04:00
Andrew Kesterson	a8526ad55e	Give an actor a say in how it answers a collision ... A seventh behaviour hook, collidefunc, defaulting to akgl_actor_collide_block. Contacts are delivered one actor at a time with the normal already pointing the way that actor has to move, which removes the "which one is a1" ambiguity that made the old physics `collide` slot unimplementable -- and means a game overriding one actor's response never has to reason about the other's. The default moves the actor out along the normal by the penetration depth and removes the component of its motion that was going into the surface. Three things about that are easy to write wrongly, and each has a test that names the symptom rather than the assertion: - **It writes `e` and `t`, never `v`.** akgl_physics_simulate recomputes velocity as `e + t` at the top of every step, so a write to `v` is discarded before anything reads it. Worse than useless: an actor holding a direction into a wall would keep accumulating thrust while standing still and leave at speed the instant the wall ended. Breaking this leaves the fall running at 300 px/s through the floor. - **It removes the component, not the axis.** Zeroing the whole thrust vector costs the actor its motion *along* the surface as well, which is a character scraping a ceiling stopping dead and a character landing on a floor losing its run. Sliding along a wall is the difference between a wall and glue. - **A separating contact is left alone.** An actor already moving out of a surface that gets its velocity zeroed is an actor stuck to a wall it is walking away from, and it reads to a player as the collision grabbing them. `e` and `t` are treated separately rather than as their sum, so an actor pressing into a floor loses its downward gravity without losing the sideways run it is also doing. A sensor is reported and never pushed -- walking through a coin is not being blocked by it. The default deliberately does not pre-load the environmental term with a step of gravity. A resolver running *before* the step has to, or the step it is correcting for re-adds gravity and commits a quarter pixel of penetration, which is invisible and still fatal because every horizontal move then reads as blocked. This library resolves after the move, so the case does not arise; the sidescroller example carries that workaround because it had no choice. Also asserted: the other six hooks survive. A seventh that displaced one of them would be a silent regression somewhere unrelated. Co-Authored-By: Claude Code <noreply@anthropic.com> Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>	2026-08-02 06:47:21 -04:00
Andrew Kesterson	e632abf720	Let a map say which layers are solid, and answer questions about them ... A tile layer with a `collidable` boolean custom property is collision geometry. Before this a game had to hard-code a layer index -- both examples do, because akgl_TilemapLayer does not retain the name Tiled wrote -- and that index changes the moment somebody reorders layers in the editor. Solid tiles are **not** given proxies. At the maximum map size that is a quarter of a million per layer, tens of megabytes of index to describe data that is already a dense grid sitting in the tilemap. The world keeps a borrowed pointer and reads layers[i].data[] over whatever cell range a query covers: nine array reads for a 32-pixel actor on 16-pixel tiles, nothing to build at level load, and nothing to maintain per frame. Static geometry that is not tile-aligned is still an ordinary proxy with AKGL_COLLISION_FLAG_STATIC; both mechanisms exist and tiles use the free one because there are a hundred thousand of them. Four public queries come with it, all of which answer without resolving: solid_at, box_blocked, query_box and settle. They are what a game reaches for when it wants to know rather than to be pushed -- a ledge probe ahead of a walking enemy, a check that a doorway is clear -- and the sidescroller cannot drop its hand-rolled collision without them. akgl_collision_settle is the one worth naming. Resolution stops a shape entering geometry and has nothing to say about one that began inside it: what it does instead is refuse every move, so an actor spawned in a wall is simply stuck. Level authors produce that constantly, so settling walks a shape up a tile at a time and refuses loudly rather than searching forever. Two defects found by writing the tests: - The fixture put an akgl_Tilemap on the stack and segfaulted before the first assertion. It is about 26 MB -- the layer and tileset arrays are sized for the worst case the format allows -- and tilemap.h says so. It is static now, with a comment saying why, because the next person to write a map fixture will reach for a local first as well. - The far-edge nudge used AKGL_COLLISION_EPSILON, which is 1e-6. That is a sensible tolerance on a unit vector and a meaningless one on a map coordinate: `float` carries about seven significant digits, so at a coordinate of 144 the smallest representable step is around 1.5e-5 and `144.0f - 1e-6f` is exactly 144.0f. The nudge did nothing, a box resting flush on the floor read as inside it, and every move it tried looked blocked -- an actor standing on the ground unable to walk. Two different quantities were sharing one constant; the tile one is now its own, at a thousandth of a pixel, which is what the sidescroller example independently arrived at. Both breaks verified: removing the nudge and ignoring the `collidable` bit each turn the suite red with the symptom named. Co-Authored-By: Claude Code <noreply@anthropic.com> Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>	2026-08-02 06:38:12 -04:00
Andrew Kesterson	68e042bd47	Add a pluggable broad phase, and the incremental uniform grid behind it ... akgl_Partitioner is a record of function pointers and an initializer, the same shape as the render and physics backends. `move` is its own slot rather than remove-then-insert, and that is the whole design: a uniform grid's move is a comparison and a return when the proxy has not left the cells it was in, which is the steady state for a walking actor and the permanent state for a static one. Spelling it as remove-and-insert would turn the incremental grid into the rebuild-every-frame tree that PERFORMANCE.md already measured and rejected. The grid is a dense 128x128 array of cell heads over the world, cells keyed on tile size, with two intrusive chains per entry -- one through the cell so a query can walk it, one through the proxy so removal unlinks a whole span without searching. Everything is an int16_t index rather than a pointer, so the structure is relocatable and clearing it is a memset. A proxy covering more cells than AKGL_COLLISION_GRID_MAX_SPAN spills onto one chain every query walks, which is what makes the cell pool's ceiling provable rather than hopeful. tests/partition.c compares every query against a linear scan over the same proxies and asserts containment in one direction, not equality. That asymmetry is the contract: over-reporting costs a narrowphase call, under-reporting is a wall an actor walks through. The suite is a table over partitioners so the same assertions run against every implementation, which is what the second one landing later will be held to. Three deliberate breaks, and two of them were not caught the first time: - Removing the min-cell rule so a shared-cell pair reports repeatedly: caught. - Dropping the unlink in `move`: **not caught**, initially. Stale entries do not produce wrong query answers, because the bounds re-check filters them out -- they leak the cell pool until the grid stops working, on a timescale no unit test reaches by accident. Counting live pool entries across 200 moves is the only thing that sees it, and now does: 505 entries against an expected 5. - Swapping floorf for a truncating cast: **not caught, and correctly so.** Everything below zero is clamped to cell 0 either way, so today the two are indistinguishable. The comment claiming truncation is a defect was overstating it and now says what is actually true: the clamp is the only thing hiding it, and a negative world origin or a relaxed clamp would make it real with no test standing in front of it. Co-Authored-By: Claude Code <noreply@anthropic.com> Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>	2026-08-02 06:29:02 -04:00
Andrew Kesterson	a3cb6ca79a	Answer whether two shapes overlap, and how to undo it ... akgl_collision_test takes two proxies and fills in a contact: a unit normal, a depth, and a point. Three paths, cheapest first. The proxies' bounds reject most pairs in four comparisons and no arithmetic, which is free because the bounds were computed when the proxy was synced. A box against a box is answered in closed form. That is not only cheaper than the general solver, it is *exact*, and the difference shows up where it matters most: an actor resting on a floor wants a normal of precisely (0, -1, 0), and an iterative solver converges to something like (0.0001, -0.99999, 0), which accumulates into a slow sideways creep. A tile game is almost entirely boxes, so this is the path that runs. Everything else goes to ccdMPRPenetration. MPR rather than GJK+EPA because MPR allocates nothing at all, converges in fewer iterations, and its one weakness -- a coarser contact *point* -- is on a field the blocking resolver never reads. EPA stays compiled and available behind the arena for a caller who one day wants an accurate manifold. The header says the point is approximate so nobody builds a damage falloff on it. The normal points out of the second shape and toward the first, so a caller moving `a` along it by `depth` separates the pair. libccd hands back the opposite convention; converting once here saves every resolver from remembering the sign, and getting it backwards would compile, would pass any "do these collide" test, and would drag actors into walls. There is a test that asserts the direction, and inverting the conversion turns it red. AKGL_COLLISION_TEST_PLANAR flattens the normal into the xy plane. The extrusion the setters apply already makes z the most expensive axis, so this is a net for a caller who set a depth by hand -- and the failure it catches is silent: the narrowphase reports a contact, the resolver pushes the actor into the screen, and the actor does not move on screen while remaining inside the floor. It also rescues the degenerate case, two shapes at exactly the same centre, where there is no planar direction at all and a zero-length normal would be a wall that stops nothing. Level authors stack things constantly. Three things the tests found rather than assumed: - The guard has two copies, one per path, and the box one is where it earns its place. Removing both is caught; removing only the iterative one is not, because the iterative solver is seeded from the line between the two centres and so converges to a planar answer on its own for a planar offset. That is measured and written down in the test rather than papered over with a fixture contrived to force it. - A concentric pair has no preferred sign on the degenerate axis, so the test asserts the magnitude of the normal rather than its direction. The first version asserted -1 and failed against an equally correct +1. - The box fast path and the iterative solver are two implementations of one answer, so they are driven over the same arrangements and required to agree on the decision and the axis. A shortcut nothing cross-checks is a shortcut waiting to diverge. Co-Authored-By: Claude Code <noreply@anthropic.com> Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>	2026-08-02 06:18:09 -04:00
Andrew Kesterson	d0b057f47a	Pool collision proxies, and tie one to the life of its actor ... A proxy is what the broad phase will index: an actor's shape, where it is, and the bounds that follow from those. It is a sixth heap layer, two per actor -- one for the actor itself and headroom for static geometry a game registers that is not tile-aligned. Solid *tiles* deliberately get none: the broad phase will read those out of the tilemap's own array, because one proxy per tile is tens of megabytes to index data that is already a grid. The pool follows the existing convention rather than improving on it. akgl_heap_next_collision_proxy finds a free slot and does not claim it; akgl_collision_proxy_initialize claims it. That is TODO.md item 8's asymmetry, and it is kept on purpose: an acquire abandoned before initialization leaks nothing, because the slot still reads as free, and a sixth pool with its own rule would be worse than one defect with five instances. Fixing item 8 means fixing all five together with every call site audited, and that is its own change. The proxy holds a *copy* of the shape rather than a pointer. An actor's own logic may rewrite its shape mid-step -- a character crouching, a projectile arming -- and a broad phase whose bounds came from a shape that has since changed is a bug that only appears when two things happen in the same frame. akgl_heap_release_actor now releases the actor's proxy. Without it the proxy holds a borrowed `owner` into a slot that has just been zeroed, so the broad phase keeps a registration whose owner reads as a free actor, and the next contact against it is a collision with nothing. Verified by removing the release and watching test_proxy_dies_with_its_actor go red. The tests pin the convention as well as the behaviour: that two acquires with no initialize between them return the same slot is asserted, not merely tolerated, so that changing the convention has to change a test that says why it exists. Co-Authored-By: Claude Code <noreply@anthropic.com> Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>	2026-08-01 23:56:21 -04:00
Andrew Kesterson	9056ff06d6	Add collision shapes, on the character and overridable per actor ... A shape is a convex volume positioned relative to an actor's origin. It lives on akgl_Character, so every goblin sharing a character shares one shape definition the way they already share speeds and the state-to-sprite map, and an actor may override it with akgl_Actor::shape_override. The flag is not redundant with an empty shape. "This actor deliberately has no collider" and "this actor has not been given one yet" are different states, and without somewhere to record the difference akgl_actor_set_character cannot tell whether it is allowed to overwrite what it finds. include/akgl/collision.h is a leaf: it names actors and tilemaps as incomplete struct pointers rather than including their headers, because both of those need akgl_CollisionShape by value and a cycle forms otherwise. The `headers` suite compiles it as the first include of a translation unit, so that property is enforced rather than merely intended -- which is why the tilemap types got struct tags two commits ago. The masks are asymmetric and the defaults are the load-bearing part: layermask ACTOR, collidemask STATIC. An actor given a shape and nothing else collides with map geometry and with no other actor. "Everything with a hitbox shoves everything else" would be a surprising default for a town full of scenery and a painful one to discover after the fact; opting in to actor-versus-actor is one bit, opting out of it would have been a hunt through every NPC a game spawns. Every shape gets a z depth, because the narrowphase behind this is three dimensional and answers with the *minimum* separating translation. A thin extrusion makes z the cheapest axis, and an actor pushed along z goes nowhere a player can see while remaining inside the floor -- a collision system reporting success while doing nothing. The ratio of 2 is the smallest for which the z overlap of any two shapes the setters build provably exceeds any planar penetration they can reach. The test for that asserts the inequality across a spread of sizes rather than asserting the constant is 2, so a change to the constant fails here rather than in a game. Two things about that test are worth recording, because the first version had both: - It could not fail. TEST_ASSERT expands to FAIL_BREAK, which reports by `break`ing, and the assertion was inside a nested `for` -- so the break left the loop rather than the ATTEMPT block and the failure evaporated. This is the hazard AGENTS.md documents for CATCH; it applies to the whole family. Verified by setting the ratio to 0.5 and watching the suite still pass, then fixing it and watching it report the 512x512 case by name. - tests/collision_arena.c had the same bug in a loop added in the previous commit, and it is fixed here too. Co-Authored-By: Claude Code <noreply@anthropic.com> Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>	2026-08-01 23:48:05 -04:00
Andrew Kesterson	46232a5ad1	Give libccd a static arena so libakgl still allocates nothing ... libakgl does not call malloc at runtime. That is stated in seven places in the manual and is AGENTS.md's second standing rule, and every object comes from a fixed array in akgl/heap.h. libccd's EPA path does not know that: it builds its expanding polytope out of realloc and free, and ccdGJKPenetration documents a -2 return for when that fails. The alternative was to compile only the three files MPR needs and leave EPA out of the build. That works and it puts a copy of somebody else's source list in this repository, where it rots silently on the next submodule bump. This instead compiles all of libccd and points its allocator at a bump allocator over static BSS, which keeps the promise literally true -- and keeps EPA available rather than amputated, for the day a precise contact manifold is worth having. The arena is reset at the top of each query rather than freed block by block, so the lifetime is one narrowphase call, `free` is a no-op, and allocation is a pointer bump. Exhaustion returns NULL, which libccd already handles by unwinding to -2, which becomes AKGL_ERR_COLLISION naming the high-water mark -- a loud failure with a number in it rather than a silently missed collision, which would be a floor an actor falls through reported as success. One GJK/EPA box pair costs 7,264 bytes, measured and printed by the suite. The 64 KB ceiling is that with about nine times headroom, and the high-water mark is reported so the next reader can re-derive it rather than trust this line. The redirect lives in src/ccd_arena_shim.h, injected with -include, and not in CMake's COMPILE_DEFINITIONS. It was in COMPILE_DEFINITIONS first, and that is a mistake worth recording: CMake cannot carry a function-like macro through a -D, so it dropped __CCD_ALLOC_MEMORY without a diagnostic. libccd went on calling the C library's realloc while the shim's `free` quietly discarded the results -- strictly worse than doing nothing, and invisible, because it leaks rather than crashes. What caught it was insisting the test prove the wiring rather than the outcome. The first version asserted the arena balanced back to zero after a query, which turned out to be the wrong assertion for a different reason -- free is a no-op by design, so it cannot balance -- but a test that had merely checked "two boxes collide" would have passed throughout, against an allocator nothing was using. The suite now asserts what is actually provable: that a query allocates from the arena at all, and that the process survives, since glibc aborts when the real free(3) is handed a pointer it never issued. Also here: AKGL_ERR_COLLISION, with the name registered -- tests/error.c asserts the band and the names agree, and it caught the missing one immediately. -fvisibility=hidden and CCD_STATIC_DEFINE keep every ccd* symbol out of libakgl.so's dynamic table, which `nm -D` confirms is empty; AGENTS.md records a shipped defect where an exported `renderer` was preempted by a same-named symbol elsewhere, and a game linking a system libccd would hit exactly that. Co-Authored-By: Claude Code <noreply@anthropic.com> Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>	2026-08-01 23:29:37 -04:00
Andrew Kesterson	842ef75ddf	Report the overlap akgl_collide_rectangles could not see ... It asked whether either rectangle enclosed one of the other's four corners -- eight akgl_collide_point_rectangle calls, stopping at the first hit. That is a different question from "do these overlap", and it has the wrong answer for one arrangement: a tall thin rectangle crossing a short wide one overlaps in a plus sign with no corner of either inside the other, and all eight tests said no. A long thin platform crossing a tall thin character is exactly that shape, so this is a shape a 2D game produces, not a curiosity. util.h carried an @note describing it and docs/18-utilities.md had a diagram of it, both under the heading of a limitation rather than a defect, and there was no test for it at all -- nor for full containment, nor for a shared edge. It is four comparisons now, on both axes. `<=` rather than `<` because akgl_collide_point_rectangle is inclusive on all four edges and these two have always agreed that touching counts; a span test written with `<` would have silently changed a contract both the header and the manual state. The test was written first and failed on the cross before the fix went in. Two answers change for a caller upgrading, and both are in the header note and the chapter: - The cross reports `true`, which is the point. - The comparison is in float rather than through akgl_Point's int members, so a sub-pixel overlap is no longer truncated away. A pickup test that was accidentally forgiving by up to a pixel is no longer forgiving. Both tutorials use this for coins and hazards; both still pass. Faster as a side effect rather than a goal, and worth recording because the numbers move a documented budget: 24.9 ns -> 6.1 overlapping, 57.9 -> 6.1 disjoint, and the all-pairs sweep over 64 actors 115 us -> 12.2. The disjoint case gained most because it was the one that ran all eight tests before answering. The three moved rows are re-recorded in PERFORMANCE.md and nothing else is. akgl_rectangle_points is untouched by this change and reads 6.1 in the same run against the 4.0 recorded, so 6 ns is this run's floor and the new figure means "too cheap to measure" rather than "exactly 6.1" -- said in the prose so the next reader does not re-baseline the table around it. Co-Authored-By: Claude Code <noreply@anthropic.com> Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>	2026-08-01 23:12:01 -04:00
Andrew Kesterson	943bf4324e	Let a control map listen to any keyboard, and fix the dead arrow keys ... The sidescroller's controls did nothing. `akgl_controller_handle_event` matched `event->key.which == curmap->kbid` exactly, with no way to say "whatever keyboard the player is typing on", so the game did the obvious thing and bound `SDL_GetKeyboards()[0]`. That cannot work. The id a key event *carries* is chosen by the video backend and is not required to be an id `SDL_GetKeyboards()` reports. On X11 without XInput2 every key event carries `SDL_GLOBAL_KEYBOARD_ID`, which is 0, while `SDL_AddKeyboard` registers the attached keyboard as `SDL_DEFAULT_KEYBOARD_ID`, which is 1; with XInput2 the events carry the physical slave device's `sourceid` while `SDL_GetKeyboards()[0]` may be the master. Either way the map matched nothing and every key press was dropped. A `kbid` or `jsid` of 0 now matches any device of that kind. 0 is safe to spend: SDL documents `which` as 0 when the source is unknown or virtual, and joystick ids start at 1, so no real device is 0. A non-zero id still matches only that device, which is what keeps two local players on two keyboards apart, and there is a test for that half too. `util/charviewer.c` already passed 0 and depended on the old behaviour by accident; it works under XInput2 now as well. Two reasons this shipped, both closed: - Every test in tests/controller.c dispatched an event whose id equalled the id the map was bound with, so none of them could see it. - The sidescroller's smoke test called the control handlers directly instead of dispatching events, so it passed against a control map that matched nothing. It now pushes synthetic events through akgl_controller_handle_event from a deliberately non-zero device id and fails if the press does not arrive. Verified by breaking the binding and watching the run exit non-zero. `test_controller_wildcard_device_ids` was written first and failed against the unfixed library with "a map bound to keyboard 0 ignored a key press from device 11", which is the whole reason to trust it now that it passes. The controls were documented, in one sentence. Chapter 19 has a proper table of them, and chapter 15 explains why not to reach for SDL_GetKeyboards(). The header said the match was exact and now says what it does. Co-Authored-By: Claude Code <noreply@anthropic.com> Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>	2026-08-01 21:23:13 -04:00
Andrew Kesterson	8ac291d2dd	Compile, link and run every example in the documentation ... libakgl exports 157 functions and the only user-facing documentation was a FAQ in README.md whose examples did not compile: two unbalanced `PASS()` calls, a `sprite->frameids = [0, 1, 2, 3];` that is not C in any dialect, a stray `9` inside a bitmask expression, an `int screenwidth = NULL`, and -- in the first snippet a reader ever saw -- the exact `strncpy` call AGENTS.md forbids. That is not a reader routing around typos. It is what happens to samples that nothing executes. This is akbasic's documentation harness with the interpreter taken out and the ability to link and run put in. The contract is a set of fence info strings, so an example is ordinary markdown that still highlights on the forge: ```c compiled with -fsyntax-only -Wall -Werror ```c wrap=NAME the same, wrapped in tests/docs_preludes/NAME.pre/.post ```c run=NAME linked against akgl and run headless ```c excerpt=PATH must still appear verbatim in PATH ```c screenshot=NAME also the source of docs/images/NAME.png ```json kind=KIND loaded through the real akgl_*_load_json ```output the exact stdout of the runnable block above it `run=` is why this links at all: -fsyntax-only proves a call typechecks, not that the startup order works or that an ATTEMPT block gives back what it took. `json kind=` exists because the asset formats are documented in prose and read by four loaders with nothing tying the two together -- util/assets/littleguy.json is already invalid against the loader it ships with. A fence with no info string is a hard error, and so is an unknown one. The failure mode this exists to prevent is passing because it quietly ran nothing, so an unannotated block is a missing decision rather than a default. Exit status is the number of failed examples; 2 for a usage error, which is a different thing and has to be distinguishable. Proven to fail on all ten of its failure modes -- untagged fence, non-compiling snippet, stale excerpt, orphan output block, unknown info string, run= output mismatch, invalid JSON, missing figure, a -Werror warning, and a dangling preload= -- because a check that has never failed has not been tested. `-Werror` here although AKGL_WERROR stays off for the library: that option is off so a new compiler's diagnostic cannot break a consumer's build, and a doc snippet is not a consumer. A sample that warns is a sample that teaches the warning. Registered as `docs_examples` and `docs_screenshots`. No docs-path filter in CI, deliberately: documentation goes stale because the code moved, not because somebody edited a chapter. Co-Authored-By: Claude Code <noreply@anthropic.com> Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>	2026-08-01 20:58:11 -04:00
Andrew Kesterson	e4aa6a5084	Take libakerror 2.0.1 and drop the workaround it makes obsolete ... Every libakgl test suite could report success while failing. libakerror's default unhandled-error handler ended in exit(errctx->status), an exit status is one byte wide, and libakgl's band starts at 256 -- so AKGL_ERR_SDL, the most common failure a library built on SDL can have, exited 0 and CTest recorded a pass. tests/character.c aborted at its second of four tests on a bad renderer and was green for months. 0.5.0 worked around that here with TEST_TRAP_UNHANDLED_ERRORS() in tests/testutil.h, and TODO.md ended the entry saying any consumer's suites have the same problem and it was worth raising upstream. It was. 2.0.1 fixes it at the source: akerr_exit() owns the mapping and the default handler calls it, so 0 exits 0, 1 through 255 exit themselves, and anything else exits AKERR_EXIT_STATUS_UNREPRESENTABLE (125). The trap and its 21 call sites are gone. Verified by putting the original failure back rather than by reading the release notes: a FAIL_BREAK(AKGL_ERR_SDL) in tests/character.c's main exits 125 and CTest reports a failure. A standalone consumer raising the same status unhandled exits 125 where it exited 0 before. tests/actor.c installs its own handler and called exit(errctx->status) from it, which is the same defect one layer up. It calls akerr_exit() now. 2.0.0 also makes the error pool and the status registry thread safe, which libakgl needs more than it knew: audio_stream_callback raises error contexts on SDL's audio thread. With an unlocked pool that callback and the main thread could scan AKERR_ARRAY_ERROR at the same time and be handed the same slot. The comment there says so. This is a hard dependency floor, not a preference. 2.0.0 moved __akerr_last_ignored to thread-local storage and made akerr_next_error() return a context that already holds its reference, and both expand at libakgl's call sites -- and at a consumer's, because akerror.h is part of libakgl's public interface. Mixing headers and libraries across that line double-counts every reference and never returns a pool slot. The soname moved to libakerror.so.2; include/akgl/error.h now also feature- tests AKERR_EXIT_STATUS_UNREPRESENTABLE, which is the narrowest probe for 2.0.1 since libakerror publishes no version macro. 0.7.0 for that reason: libakgl's own ABI is unchanged, but the one it re-exports through its headers is not. TODO.md records the pkg-config gap this makes sharper -- akgl.pc names no dependencies at all, so nothing tells a pkg-config consumer which libakerror it needs. Clean build, 26/26 ctest, memcheck clean, warning-clean at -Wall -Werror. libakgl.so.0.7 links libakerror.so.2. Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01B8T5FAYXE8HEJqFLCYwNNc	2026-08-01 13:05:43 -04:00
Andrew Kesterson	1b90f2ebd5	Report the failures libakstdlib's wrappers were already catching ... Updates deps/libakstdlib to 669b2b3. That commit is a TODO entry rather than new code, so the interesting part is what libakgl was not yet calling: it links libakstdlib and uses ten of its wrappers while calling the raw libc function at a good many more sites. Four of those were carrying a real defect. akgl_game_save checked every write and threw away the close. Every write goes through aksl_fwrite, and for a record this size all of them land in stdio's buffer -- nothing reaches the device until the close flushes it, so a full disk, an exceeded quota or an NFS server going away is reported only there. The function returned success over a savegame that was never written. aksl_fclose surfaces it. tests/game.c reaches the path through /dev/full, which accepts writes and fails at the flush; against the unfixed code the test reports "expected a failure, got success" with ENOSPC. The close has to drop the FILE * before the status is examined, because fclose(3) disassociates the stream either way and CLEANUP would close it again. Written the other way round it aborted in glibc with "double free detected in tcache" the first time a close actually failed, which is how that ordering was found. akgl_game_load's end-of-file check used fgetc(3), which spells "end of file" and "the read failed" with the same EOF -- a disk error there read as a clean end and passed the check it was meant to fail. aksl_fgetc tells them apart. Extracted to require_at_eof, because inverting the sense of a call inline needs a nested ATTEMPT whose break binds to the wrong switch. Two snprintf sites were truncating under a silenced -Wformat-truncation. The compiler was right about both. The tileset one handed the shortened path to IMG_LoadTexture, so a length error was reported as a missing file, with SDL naming a path the caller never wrote. Both use aksl_snprintf now and the suppression is gone; nothing in the tree uses those macros any more. tests/tilemap.c covers the join, and against the unfixed code it gets AKGL_ERR_SDL where it wants AKERR_OUTOFBOUNDS. The two src/game.c strncpy sites the fixed-width copy sweep missed -- the savegame name field and the libversion stamp -- use aksl_strncpy and sizeof rather than a repeated 32. Also makes tests/physics_sim.c deterministic. It placed gravity_time at "now - dt" and let the real clock supply the step, so a machine busy enough to deschedule the process between that store and the SDL_GetTicksNS() inside simulate got a longer step. It went red once, under a parallel ctest. It now sets max_timestep to the step it wants and gravity_time to zero, so the bound supplies the step and the scheduler cannot reach it. TODO.md records what is deliberately not adopted: the pure-arithmetic wrappers, which can only fail on NULL and which the tree already spells two ways, and the collections, which the registries do not want because SDL owns the property-set lifetime. AGENTS.md has the rule and the fclose ordering trap. 26/26 ctest, memcheck clean, warning-clean at -Wall -Werror. Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01B8T5FAYXE8HEJqFLCYwNNc	2026-08-01 12:36:36 -04:00
Andrew Kesterson	147ab7dc78	Fix three arcade physics defects the unit tests could not see ... tests/physics_sim.c runs the arcade backend the way a game does -- a Mario-esque jump and fall, Zelda-style top-down walking, and a run reversed at full speed -- and prints what the actor actually did. tests/physics.c already checked that akgl_physics_simulate does the arithmetic it claims. Every one of these got past it. The first step was however long the level took to load. gravity_time was never initialized and dt was unbounded, so a 250 ms load produced a 250 ms step: 100 px of fall where a 60 Hz frame under the same gravity is 0.44 px, straight through whatever was underneath. Both initializers seed the clock, and simulate bounds dt to max_timestep -- a new physics.max_timestep property, default 0.05 s, read like gravity and drag. Zero disables the bound. The field replaces the dead timer_gravity, so the struct is the same size. Releasing a vertical key cancelled gravity. The _off handlers zeroed ay, ey, ty and vy together, and ey is where the arcade backend accumulates gravity -- tapping down mid-jump stopped the character in the air. They clear ax/tx (or ay/ty) and nothing else now. Velocity was never theirs to clear either: simulate recomputes v as e + t every step. Diagonal movement was 41% too fast. Thrust was capped per axis, so an actor holding two directions got both caps at once and travelled their diagonal. It is capped as a vector against the sx/sy/sz ellipse, which also keeps a character whose horizontal and vertical top speeds differ moving at the ratio it asked for. An axis with a zero max speed stays out of the magnitude and is forced to zero, as the old clamp did. Each fix was checked by reverting it and confirming the simulation goes red: 100.1 px, vy 0.0 after a down tap, and 141% diagonal respectively. tests/actor.c and tests/physics.c pinned the old behaviour in both places and now assert the new contract. Bumped to 0.6.0: akgl_PhysicsBackend changed. TODO.md records the four things the simulations found and this does not fix -- no terminal velocity, no deceleration on release, Euler's frame-rate dependence, and a drag coefficient large enough to invert velocity. 26/26 ctest, memcheck clean, warning-clean at -Wall -Werror. Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01B8T5FAYXE8HEJqFLCYwNNc	2026-08-01 12:10:53 -04:00
Andrew Kesterson	4d80664cd9	Build clean under -Wall, with -Werror in CI only ... TODO.md item 37 said the cast sweep buys nothing until the build turns on the warnings those casts suppress. This is that precondition, and the argument turned out to be right with evidence: -Wall found three genuine signedness mismatches in sprite.c, where uint32_t width, height and speed were passed straight to akgl_get_json_integer_value(..., int *). A cast would have silenced all three. Fixing them properly also turned up that speed is scaled by a million into a 32-bit field, so anything past 4294 ms overflowed rather than being held. The other real finding was ten -Wstringop-truncation warnings, every one a fixed-width strncpy. Those leave a name field unterminated when the input fills it -- and those fields are registry keys, handed to strcmp and SDL property calls that do not stop at the field. Same overread class fixed twice already this release. All ten now use aksl_strncpy from akstdlib, which always terminates and never NUL-pads, bounded to size - 1 so an over-long name still truncates rather than being refused. staticstring.h documented the old strncpy semantics explicitly and has been rewritten to match. Two sites in game.c are deliberately left on strncpy: both stage into a pre-zeroed buffer for the savegame's fixed-width fields, where the NUL padding is part of the format. Neither is flagged. sprite.c also had a memcpy of a full 128-byte field from a NUL-terminated string, which reads past the end of any shorter name. Not flagged by anything; found while converting its neighbours. -Werror is an option, default OFF, on only in the cmake_build and performance CI jobs. libakgl is consumed with add_subdirectory -- akbasic does exactly that -- so a target-level -Werror turns every diagnostic a newer compiler invents into a broken build for somebody else. The warning set is not even stable across build types here: an -O2 build reports ten warnings that -O0 and -fsyntax-only do not, because they need the middle end. The two jobs that set it are one of each. -Wextra is deliberately not adopted. It adds 22 findings, 17 inherent to the design: 13 -Wunused-parameter from backend vtables and SDL callbacks that must match a signature, and 4 -Wimplicit-fallthrough from libakerror's own PROCESS/HANDLE/HANDLE_GROUP, which fall through by design. Filed upstream as deps/libakerror TODO item 8; the submodule bump carries it. deps/semver/semver.c is listed directly in add_library, so the target's PRIVATE options reach it. Exempted with -w so a future semver update cannot fail this build -- verified by forcing -Wextra -Werror and watching our files fail while semver compiled clean. Verified: RelWithDebInfo, Debug and coverage builds all clean under -Werror; -Werror actually fails on a planted unused variable; an embedded consumer with AKGL_WERROR unset still configures and builds. 25/25 pass, memcheck clean, reindent --check, check_api_surface and check_error_protocol clean. Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>	2026-08-01 09:18:52 -04:00
Andrew Kesterson	28fa929f6a	Make savegames, optional array elements, empty text and coverage work ... Closes Known-and-still-open items 7 and 13, and Defects items 18, 25 and 27. The savegame name tables carry no length prefix, so writer and reader have to agree on a field width exactly. The writer used each object's own maximum name length -- 512 for a spritesheet, a filename -- and the reader used AKGL_ACTOR_MAX_NAME_LENGTH for all four. Four AKGL_GAME_SAVE_*_NAME_WIDTH constants drive both sides now. The failure turned out to be worse than "cannot be read back": a reader stepping the wrong width does not run off anything, it finds a run of zeros inside an entry, stops early, and reports success with silently wrong maps. A test asserting only that the load succeeded passed against the broken reader. So akgl_game_load checks it is at EOF once the tables are read, which turns a width disagreement into AKERR_IO instead of a corruption. That is the assertion the new roundtrip test -- the first with all four registries populated -- hangs on. akgl_get_json_with_default gains a third HANDLE_GROUP for AKERR_OUTOFBOUNDS, which is what the array index accessors report, so "this element is optional" works for an array element and not only for an object member. The arm goes above the one holding the memcpy: HANDLE_GROUP emits no break and every arm falls into that body. That test needed a second attempt. with_default returns *the context it was given* when it does not handle the status, so TEST_EXPECT_OK -- which releases whatever the statement returns -- double-released it against a CLEANUP block that released it too, and a double-released context corrupts the failure rather than reporting it. The first draft passed against the unfixed library. akgl_text_rendertextat returns success without rasterizing for the empty string, matching akgl_text_measure, which has always accepted it. The check sits after the font and backend guards, so drawing nothing still refuses what drawing something refuses. tests/text.c had this case written and unasserted waiting for the two halves of the header to agree. character_load_json_state_int_from_strings guards dest rather than testing states twice. Not asserted: the function is static with one call site that passes a real pointer, so the guard cannot fire, and reaching it from a test would mean giving it external linkage purely for that. Both gcovr invocations take the build tree as an explicit positional search path. gcovr searches --root when given none, which is the source directory, where build trees live; --object-directory does not narrow it. Verified by building two instrumented trees with a source edit between them: the old invocation fails with "Got function write_exact on multiple lines: 46, 48" and exits 64, the new one exits 0 and the full coverage run passes with the stale tree still present. 25/25 pass, reindent --check, check_api_surface and check_error_protocol clean. Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>	2026-08-01 07:34:51 -04:00
Andrew Kesterson	913834a3af	Draw actors at their sprite's height, and update each one once a frame ... Closes Defects item 26 and Performance item 32. akgl_actor_render set dest.h from curSprite->width, so every actor was drawn square and a non-square sprite was stretched or squashed. Invisible in the fixtures because they are all square, so tests/actor.c gets a 48x24 sprite and a render backend whose draw_texture records the rectangle it is handed instead of drawing it. That recording backend is the first coverage akgl_actor_render has had at all -- every other test in the file stubs renderfunc out. akgl_game_update looped over AKGL_TILEMAP_MAX_LAYERS with the actor sweep nested inside it and never compared an actor's layer to the layer it was on, so every live actor's updatefunc ran sixteen times a frame. The sweep is hoisted out: updating an actor is not a per-layer operation, and akgl_render_2d_draw_world already walks the layers for the half that is. AKGL_ITERATOR_OP_LAYERMASK is honoured rather than ignored now, so a caller who wants one layer can still ask, and gets each of those actors once. Counting is the assertion, deliberately. The defect was invisible in the frame total because the tilemap blits are three orders of magnitude larger, so a timing test would have measured the rasterizer. tests/game.c counts calls into a stub updatefunc and reports 16 against the old code. PERFORMANCE.md records the timing side as what it honestly is: the gap between the akgl_game_update and draw_world rows of the same run, 92 us before and noise in both directions after. The absolute table is not re-taken -- a later run on this machine read every row about 15% high, including rows nothing has touched. 25/25 pass, reindent --check clean. Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>	2026-08-01 07:34:27 -04:00
Andrew Kesterson	9c2f80bcb9	Give back every pooled string and sprite reference the loaders take ... Closes Defects items 20, 22, 23 and 29, and the residual of item 38. The tilemap load leak was five pooled strings per load; the property-lookup fix in an earlier commit took it to two, and the last two were each a claim with no matching release -- the string every layer's `type` was read into, and the dirname the map's relative paths resolve against. tests/tilemap.c asserts the pool is exactly where it started after one load/release cycle and after 64. Finding those two was a matter of dumping the contents of every still-claimed slot after a cycle rather than reading the code again; 'tilelayer' and an assets directory named themselves immediately. Same file, same class, fixed with it: akgl_tilemap_load_layer_objects released its scratch string after reading each object's name and then kept using the slot, because akgl_get_json_string_value reuses a non-NULL destination without taking another reference. The slot was free while still live, so any other claim could have been handed it. akgl_character_sprite_add wrote over an existing binding without releasing the sprite it displaced, so a character that rebinds a state while alive leaked a sprite slot per rebind -- teardown only gives back what the map holds at the end. The new reference is taken before the write and given back if the write fails, so there is no window where a sprite is bound with nothing behind it. The write was unchecked too. Three failure-path leaks moved into CLEANUP blocks: akgl_render_2d_init's two pooled strings, akgl_controller_open_gamepads' enumeration array, and akgl_text_rendertextat's surface and texture -- the last being a leak per frame on a HUD line. akgl_text_unloadallfonts() closes every font in the registry and destroys it, which is what item 38 left open. Deliberately not a whole akgl_game_shutdown: tearing down the mixer, SDL_ttf and SDL in the right order is a design question, and this is the part that was simply missing. It is a new public symbol, which 0.5.0 already covers -- this release has not shipped. Every fix has a test that fails against the old code. 25/25 pass, memcheck clean, reindent --check, check_api_surface and check_error_protocol all clean. Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>	2026-08-01 07:33:55 -04:00
Andrew Kesterson	8a90cbf275	Drop the perf suite's lowfpsfunc workaround, and record item 31 ... akgl_game_update_fps installs the default itself now, so the benchmark no longer has to. Leaving the hook NULL there is what keeps that true. Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>	2026-08-01 07:33:38 -04:00
Andrew Kesterson	21d69192e3	Report the failures that used to be crashes ... Closes Defects items 30 and 31 and Known-and-still-open items 1, 2, 5, 9 and 11. Both string accessors in json_helpers.c ended their ATTEMPT block with FINISH(errctx, false), which swallows the failure, and then strncpy'd through the pointer akgl_heap_next_string never set. So the one condition the pool exists to report -- it is full, which in practice means something is not releasing -- arrived as a segfault somewhere else entirely. It is FINISH(errctx, true) now, and tests/json_helpers.c claims every slot and asserts AKGL_ERR_HEAP comes back out of both. That test segfaults against the old code, which is also how the tilemap leak test in the previous commit confirmed this one. akgl_tilemap_release tested layers[i].texture and destroyed tilesets[i].texture, so every tileset texture was freed twice on one release and no image layer's texture was freed at all. Pointers are cleared as they go, so a second release is safe instead of a use-after-free. akgl_game_update_fps called game.lowfpsfunc() unguarded, on a path taken on frame one because fps is 0 for the first second. Only akgl_game_init installs it, and renderer.h documents the other path deliberately -- a host that owns its window binds a backend instead. It installs the default when it finds NULL. akgl_controller_pushmap and akgl_controller_default checked only the upper bound, so a negative id indexed before akgl_controlmaps. The two test-harness helpers were quietly worthless. akgl_render_and_compare drew t1 on both passes, so it always reported a match and every image assertion built on it asserted nothing; and akgl_compare_sdl_surfaces memcmp'd s1->pitch * s1->h bytes out of both surfaces without checking that the second was the same size, so a smaller one was read past its end. Both fixed, both tested. tests/util.c also now calls the collide-point test it has defined and never run. 25/25 pass, memcheck clean, reindent --check and check_error_protocol clean. Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>	2026-08-01 07:33:37 -04:00
Andrew Kesterson	230278d303	Bound every array a data file can index ... Closes Defects items 16 and 17 and Known-and-still-open item 6. All three let an asset file, or a caller's argument, write past a fixed array. akgl_sprite_load_json took its frame count straight from the document and wrote that many entries into a 16-byte frameids -- through a uint32_t * cast of a uint8_t *, so each write touched four bytes and the overrun reached four bytes past the array, into the rest of akgl_Sprite and then the next pool slot. The count is checked first now, each id is read into an int and narrowed deliberately, and a frame number too large for a uint8_t is refused rather than truncated into an index for a different tile. The tilemap loader had the same shape twice: objects[j] with no check against AKGL_TILEMAP_MAX_OBJECTS_PER_LAYER and tilesets[i] with none against AKGL_TILEMAP_MAX_TILESETS. akgl_tilemap_load_layers already bounded its own loop, so the pattern was in the same file. The object one is the reachable half -- 128 objects is not a large object layer. akgl_string_initialize zeroed sizeof(akgl_String) starting at `data`, which begins after the refcount in front of it, so it ran four bytes past the end of the object and onto the *next* slot's refcount -- the field the allocator reads to decide whether a slot is free. Same file, same class, fixed with it: akgl_string_copy accepted a count larger than the buffers, reading past one pool slot and writing past another, which the header documented as behaviour. Every case has a test that fails against the old code, with five new fixtures. Exactly-the-maximum is asserted alongside one-past in each, so the bound cannot be fixed by making the limit off by one. 25/25 pass, memcheck clean, reindent --check clean. Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>	2026-08-01 07:33:37 -04:00
Andrew Kesterson	19530f6a97	Fix the type, macro and state-table defects, and the leftover debris ... Closes internal-consistency items 19 through 36, 38 and 41. Item 37, the ~180 redundant casts, is deliberately left open with its reasoning in TODO.md: the benefit only arrives once the build turns on the warnings those casts suppress, and doing it before that is churn across the two files with the most outstanding functional defects. The two that were real bugs are in the actor state table. AKGL_ACTOR_STATE_STRING_NAMES was declared [AKGL_ACTOR_MAX_STATES+1] and defined [32], so a consumer trusting the declared bound read past the object; and indices 11 and 12 were named UNDEFINED_11 and UNDEFINED_12 where actor.h has MOVING_IN and MOVING_OUT, so no character JSON could bind a sprite to either state. tests/registry.c now walks the whole table -- every entry non-NULL, every entry resolving to its own bit, no two entries sharing a name. The bitmask macros are parenthesized and AKGL_BITMASK_CLEAR has lost the semicolon inside its body. Writing tests/bitmasks.c for that turned up something worth knowing: the obvious test does not catch it. For a bit that is set, the misparse `!(mask & bit) == bit` gives the same answer as the correct one. It only diverges for an unset bit whose value is not 1, and that is the shape the suite uses now. akgl_draw_background was the last public function outside the error protocol. It takes a backend like everything else in draw.h, restores the draw colour it found, and is tested -- TODO.md had it filed under "needs the offscreen renderer harness", which was never true; what it needed was to stop reading the global. All eight registry initializers go through one helper, so the seven that leaked an SDL_PropertiesID on every call after the first no longer do. Fixed in the same place because it is the same function: akgl_registry_init never called akgl_registry_init_properties, which made akgl_set_property a silent no-op for anyone not going through akgl_game_init -- Defects, Known and still open item 3. Also: AKGL_COLLIDE_RECTANGLES (three open parens, two closes) and akgl_Frame deleted, float32_t/float64_t used consistently, the developer-specific debug logging removed from the controller inner loop, the abandoned SDL_GetBasePath comments removed, nine unused locals removed, and dst renamed to dest. akgl_game_update's default flags no longer OR the same bit twice. That changes nothing today, and the reason is Performance item 32: the loop never reads either bit, which is why every actor is updated sixteen times a frame. Still open. 25/25 pass, memcheck clean, reindent --check clean. Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>	2026-08-01 07:33:36 -04:00
Andrew Kesterson	76ea04205c	Stop returning past CLEANUP, and validate the arguments every sibling validates ... Closes internal-consistency items 16 and 17. Ten *_RETURN macros sat inside ATTEMPT blocks, which return past CLEANUP and skip every release in it. The one that mattered was the success path of akgl_get_json_tilemap_property: it leaked two of the string pool's 256 entries on every lookup that *found* what it was asked for, and a map load does that several times per layer. tests/tilemap.c now runs each of its three paths -- found, absent, wrong type -- twice the pool size and asserts the pool is where it started. Against the old code that test does not merely fail, it segfaults, which is Defects item 30 seen from the outside: pool exhaustion arriving as a NULL strncpy rather than as AKGL_ERR_HEAP. Two of the conversions needed more than swapping the macro. In akgl_get_json_tilemap_property a plain break would have fallen through to the "property not found" FAIL_RETURN after FINISH, reporting a miss for something found, so the success path sets a flag. In akgl_collide_rectangles the eight early exits are followed by `*collide = false;`, which would have overwritten the hit that broke out; each corner test writes the flag itself, so that line is gone rather than moved. The same function also released its scratch string once per loop iteration while continuing to use it, so the slot was free while still live -- one claim now covers the whole scan. akgl_controller_default is the other behavioural one: its SUCCEED_RETURN was the last statement in the ATTEMPT block, so the path that falls out of FINISH reached the closing brace of a non-void function. scripts/check_error_protocol.py keeps both rules enforced -- a *_RETURN inside ATTEMPT, and a return out of a HANDLE block -- as the error_protocol test. Neither produces a compiler diagnostic and neither fails a test run until the pool it drains is empty, which is why both have already shipped once. For item 17: the eight typed JSON accessors that validated their container and then wrote through dest unconditionally now check key and dest as the two string accessors always did; the null physics backend checks its actors like the arcade one; and akgl_render_2d_frame_start, _frame_end and _shutdown check self, which the first two read straight through. tests/renderer.c calls all three with NULL, which segfaulted before. 25/25 pass, memcheck clean, reindent --check clean. Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>	2026-08-01 07:33:35 -04:00
Andrew Kesterson	3a262bee54	Give every exported function a declaration, and check that it stays that way ... Closes internal-consistency items 7 through 15. Nineteen non-static functions were in the ABI with no declaration anywhere, so no consumer could call them and any consumer could collide with them. The four gamepad_handle_* functions are the ones that mattered: controller.h declared akgl_controller_handle_button_down and three siblings that did not exist, so anything compiled against the header alone failed to link. The definitions carry the declared names now, which also closes Defects -> Known and still open item 10, and their documentation moved to the header. The rest are either declared under a "part of the internal API" block -- akgl_game_save_actors and akgl_game_load_versioncmp, which tests/game.c had to declare for itself, plus six tilemap loader helpers the untested-loader work wants to reach -- or static, which is what the four save iterators and load_objectnamemap should always have been. akgl_path_relative_from is deleted: declared nowhere, called from nowhere, never wrote its output, and leaked a pooled string on every call, so it closes Known and still open item 4 and item 40 by ceasing to exist. scripts/check_api_surface.sh keeps it closed. It reads the built library's dynamic symbol table and every public header with comments stripped, and fails on an exported akgl_* symbol that is declared nowhere. Stripping comments is the whole point -- four of these were mentioned in controller.h prose, which is how they went unnoticed. The pool-size ceilings are defined once, in heap.h, so the #ifndef override hook fires for the first time; actor.h, sprite.h and character.h were defining the same four unconditionally from headers heap.h includes above its own guard. tests/header_pool_override.c fails the compile if that regresses. Also here: (void) rather than () on the twelve no-argument entry points, AKERR_NOIGNORE only on declarations, static helpers with the akgl_ prefix dropped, and the six parameter-name mismatches. akgl_get_json_with_default had its two contexts swapped rather than merely misspelled -- the incoming one was `err` and its own was `e`, which is the name reserved for an incoming one. 24/24 pass, reindent --check clean. Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>	2026-08-01 07:33:35 -04:00
Andrew Kesterson	9924d74dcc	Namespace every exported symbol, and bump to 0.5.0 ... Closes internal-consistency items 1 through 6, 12 and 13. Every include guard is _AKGL_<FILE>_H_, every in-project header include is angled, and every exported function, type and global carries the akgl_ prefix. This is an ABI break; the soname goes to libakgl.so.0.5. TODO.md carries the full rename table. The renames were driven by renaming each declaration and letting the compiler find the uses, not by pattern substitution: renderer, physics and camera are also parameter and struct-member names, and a sed would have rewritten map->physics and every akgl_RenderBackend *renderer parameter without a word. Item 4 turned out not to be cosmetic. The library exported a global called renderer and tests/character.c defined an SDL_Renderer *renderer of its own; the executable's definition preempted the library's, akgl_sprite_load_json read a SDL_Renderer * through an akgl_RenderBackend *, and every texture load in that suite failed. The suite reported success anyway, because libakerror's unhandled-error handler ends in exit(errctx->status), exit keeps only the low byte, and AKGL_ERR_SDL is exactly 256. So character had been green while running one of its four tests, and every suite in the tree was unable to fail on the most common status in a library built on SDL. Both are fixed. tests/testutil.h gains TEST_TRAP_UNHANDLED_ERRORS(), which collapses any status a byte cannot carry onto 1, and every suite installs it. character binds a real backend with akgl_render_2d_bind. Its fourth test then runs for the first time and fails on a defect it has asserted all along, so akgl_heap_release_character now walks state_sprites with AKGL_ITERATOR_OP_RELEASE and destroys the property set before zeroing the slot -- TODO.md Defects item 21 and half of Carried over item 1. AKGL_TIME_ONESEC_MS said "one second in milliseconds" and held 1000000, so akgl_game_state_lock waited roughly sixteen minutes rather than one second. It is AKGL_TIME_ONEMS_NS now, the budget is its own named constant, and tests/game.c holds the mutex from a second thread to assert the wait -- the contended path had no coverage at all. Headers are self-contained and it is enforced: AKGL_PUBLIC_HEADERS drives both install() and a generated translation unit per header, so a header that ships is a header that is checked. Writing that found registry.h, which used SDL_PropertiesID in eight declarations and included no SDL header. 23/23 suites pass, memcheck is clean, reindent --check is clean. Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>	2026-08-01 07:33:35 -04:00
Andrew Kesterson	fb58bb01b0	Fix every memory defect the checker found, and bump to 0.4.0 ... Six findings, all of them libakgl's, all closed. The memcheck run is clean. Not one of the four json_load_file calls in src/ was ever matched by a json_decref, so every asset load abandoned its parsed document: 1.5 KB per sprite, 2.1 KB per character, 9 KB per load of the 2x2 fixture map, and on the order of a megabyte for a real one. Each loader now releases it in the CLEANUP block it already had, on the success path as well as the failure one. akgl_registry_load_properties needed its loop moved inside the ATTEMPT block first: props is a borrowed reference into the document and is read after the block ends, so every exit from that loop leaked the whole tree. akgl_get_property copied a fixed AKGL_MAX_STRING_LENGTH bytes out of what SDL handed back, which is SDL's strdup of the value -- four bytes for "0.0". That read up to 4 KiB past the end of somebody else's allocation on every property read, returned whatever was there past the terminator, and would have faulted on a value that landed at the end of a page. It copies the value and its terminator now, and refuses a value too long for an akgl_String rather than truncating it into an unterminated buffer. The header note that described the overread as a quirk describes correct behaviour instead. The four savegame name tables wrote a fixed-width field starting at the registry key, and SDL sizes that allocation to the name. They read past it on every entry and put what they found into the save file: up to half a kilobyte of this process's heap per registered object, in a file a player might send to somebody. They stage through a zeroed buffer now, and a negative-array-size typedef fails the build if a table's width ever outgrows it. akgl_controller_list_keyboards never freed the array SDL_GetKeyboards allocated for it. A font could be opened and published and never handed back -- there was no way to close one, so a game that changed fonts between scenes leaked ten kilobytes each time, and loading over a live name leaked the font it displaced. akgl_text_unloadfont is that missing half, and akgl_text_loadfont calls it when it replaces a name, after the new font has opened so a failed reload leaves the caller with the font they had. A new public symbol takes the version to 0.4.0 and the soname with it: an 0.3 consumer cannot be handed this library and told it is the same ABI. tests/registry.c fills a destination with a sentinel and asserts the bytes past the terminator survive a read, which fails against the old copy. tests/text.c covers unload, double unload, unloading a name that was never registered, and replacement closing the displaced font. The JSON releases have no test of their own and cannot sensibly have one -- nothing in the public API can observe a jansson refcount -- so the memcheck run is their test, which is an argument for gating it rather than against. The two remaining findings are in deps/semver's own unit test, which is vendored. They are suppressed by function name, so a rewrite of those cases comes back as a finding. Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>	2026-07-31 15:49:11 -04:00
Andrew Kesterson	af304dc2f9	Check memory with the suites that already exist ... `cmake --build build --target memcheck` runs every registered CTest suite under valgrind. There are no new test programs, and there should not be any: tests/benchutil.h notices valgrind in LD_PRELOAD and drops the benchmark scale to 0.0005, which turns the perf suites into the broadest path coverage in the tree at a cost valgrind can survive. A benchmark walks one path a hundred thousand times; a leak check wants every path walked once. Same binaries, one flag apart, and the whole run is about thirty seconds. scripts/memcheck.sh wraps `ctest -T memcheck` because that command records defects and still exits 0, which cannot gate anything. It also forces the headless drivers, so the vendor GPU stack is never loaded -- that removes thousands of unfixable findings inside amdgpu_dri.so without suppressing anything, and it is what the suites are written for anyway. Only definite losses, invalid accesses and uninitialised reads count; "still reachable" is what SDL and FreeType keep for the process lifetime and says nothing about this library. The three suppressions in scripts/valgrind.supp are each a decision that a finding belongs to somebody else. Six defects, all filed in TODO.md under "Memory checking", the first of which is the one that matters: not one of the four json_load_file calls in src/ is ever matched by a json_decref, so every asset load abandons its parsed document -- 1.5 KB per sprite, 2.1 KB per character, 9 KB per load of the 2x2 fixture map, and on the order of a megabyte for a real one. A game that reloads a level on death leaks a level's worth of JSON every time. akgl_get_property also reads up to 4 KiB past the end of every property value it copies, and the savegame name tables read past the end of every registry key and write what they find into the file. tests/util.c zeroes three fixtures it used to leave as stack garbage. The library was never at fault there -- the tests handed it uninitialised floats and then made one real call with them -- but sixteen findings of noise in a new gate is how a gate gets ignored. The unit suites' TIMEOUT goes from 30 to 300 because CTest applies the same property to the checked run, where everything is twenty times slower. Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>	2026-07-31 14:59:57 -04:00
Andrew Kesterson	bcd49fc5b1	Measure the library: perf suites, a recorded baseline, and targets ... tests/perf.c and tests/perf_render.c drive the hot paths hard enough to time them -- pool acquire and release at both ends of the scan, the registry, the state-to-sprite lookup, the per-actor update and render, the physics sweep, an all-pairs collision sweep, the JSON accessors, path resolution, the drawing primitives, text, asset loading, a screenful of tiles, and a whole frame through akgl_game_update. They are registered like any other suite but carry the `perf` label, so `ctest -L perf` runs only them and `-LE perf` leaves them out. Every measurement is held to a budget at roughly ten times the recorded baseline, enforced only in an optimized build at full scale. Three things had to be got right before the numbers meant anything, and each was wrong first: - No error checking inside the clock. PASS and CATCH call akerr_valid_error_address, which walks AKERR_ARRAY_ERROR -- more work than several of the calls being measured. - Flush the renderer before stopping it. SDL batches, so the first version measured queueing, reported a tilemap frame 250 times faster than it is, and paid the real cost at teardown inside SDL_DestroyTexture. - A drawing benchmark needs a raw-SDL control doing the same pixel work with the same access pattern. With one, akgl_tilemap_draw turns out to cost 0.2% of the frame it appeared to own: 16.26 ms against a control's 16.23 ms for the same 1200 blits. The rasterizer is the frame. PERFORMANCE.md records the baseline, the frame budget it adds up to, and what the numbers say -- including that the string pool's acquire is 64x slower full than empty because it is a megabyte of PATH_MAX buffers, that a handled missing-sprite condition costs nine times the update it replaces, that text rasterizes and throws away a texture on every call, and that 28 MB of the library's BSS is one akgl_Tilemap. TODO.md gains a Performance section: five defects the stress tests found that the unit suites do not reach (a tilemap load leaking five pooled strings, two JSON accessors that turn pool exhaustion into a segfault rather than AKGL_ERR_HEAP, akgl_game_update crashing without akgl_game_init, and its actor update sweep running once per tilemap layer), and eighteen targets with today's number and whether it is met. Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>	2026-07-31 14:24:05 -04:00
Andrew Kesterson	c6227545a6	Release the error context when a path resolves against its root ... akgl_path_relative took its ENOENT branch by returning from inside the HANDLE block, which skips the RELEASE_ERROR that FINISH ends with. The handled context was never given back, so one entry of AKERR_ARRAY_ERROR was lost per call and the 129th call hit "Unable to pull an error context from the array!" and exited the process. That branch is not an edge case: every asset path inside a tilemap is resolved relative to the map's own directory, so it is taken several times per map load. A game that loaded fifty levels died in the loader. It was found by a benchmark that loaded the fixture map in a loop, which is the first thing in this tree to call it more than a hundred times. The fallback now runs after FINISH, so the context is released on the way past. tests/util.c resolves AKERR_MAX_ARRAY_ERROR * 2 paths through the branch and asserts the pool is where it started -- against the old code that test does not fail, it terminates the suite. Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>	2026-07-31 14:23:47 -04:00
Andrew Kesterson	57bf1c7649	Include actor.h from controller.h so the header compiles on its own ... controller.h declares three handler pointers taking an akgl_Actor * and included nothing that declares that type, so any translation unit reaching for it before akgl/actor.h failed with "unknown type name 'akgl_Actor'". src/controller.c never noticed because it includes akgl/game.h first, and tests/controller.c carried a comment explaining the workaround. Included rather than forward-declared: akgl_Actor is a typedef of a named struct and repeating a typedef is C11, not C99. It closes no cycle -- actor.h reaches only types.h and character.h. tests/headers.c is a whole suite for one #include on purpose. A second #include after the first proves nothing about the second, because by then the first has dragged its dependencies in; covering another header means another file shaped like this one. Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>	2026-07-31 12:53:09 -04:00
Andrew Kesterson	a3eada1b3f	Carry modifiers and composed text in the keystroke ring ... The ring held a keycode and dropped the rest of the event, so a line editor built on akgl_controller_poll_key() could not reach a single shifted character: no double quote, no colon, no parenthesis, and no lower case. The modifier state was discarded two layers below the caller, and polling SDL_GetModState() at read time cannot recover it -- the key is long released by then, which is the point of a ring. akgl_Keystroke carries the keycode, the modifiers and the UTF-8 text SDL composed, and akgl_controller_poll_keystroke() hands back all three. akgl_controller_poll_key() is unchanged for its callers: a game asking whether the up arrow was pressed already gets what it wants. The text comes from SDL_EVENT_TEXT_INPUT, which is the only correct way to get a character out of SDL, and is attached to the press still waiting for it -- tracked with a flag rather than by "whatever entry is newest", so a press dropped by a full buffer cannot hand its text to an older key. Text with no press behind it (an IME commit, a dead key) is buffered on its own with keycode 0, and the keycode-only poller discards those on the way past. Oversized text is cut on a code point boundary, and a sequence the string ends in the middle of is dropped rather than read past its terminator. Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>	2026-07-31 12:52:38 -04:00
Andrew Kesterson	34a076b851	Add akgl_audio_sweep for a note that changes pitch ... BASIC's SOUND ramps a tone's pitch toward a limit, and nothing here could do it. Faking it from the caller means re-issuing tones from its own step loop, which ties audible pitch to how often that loop runs -- a siren that changes shape with the frame rate. The step has to be taken on the mixer's frame counter, which only this library can see. akgl_audio_sweep(voice, from_hz, to_hz, step_hz, ms) steps once every 1/60 second, the rate the machine this vocabulary comes from used, which divides 44100 exactly so a step always lands on a whole frame. Direction comes from the two frequencies rather than the sign of the step, the last step clamps to the target, and equal frequencies are a held tone rather than an error. akgl_audio_tone() is the same start path with a step of 0, so a voice reused for a plain tone stops sweeping. A swept voice accumulates its phase instead of deriving it from the frame counter: deriving assumes a constant frequency and would jump the waveform at every step. tests/audio.c drives the mixer by hand and asserts the exact frame the pitch moves on. Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>	2026-07-31 12:52:21 -04:00
Andrew Kesterson	42b53dcb20	Check the renderer backend before drawing text ... akgl_text_rendertextat() called renderer->draw_texture() with no check on the global renderer, its sdl_renderer or the function pointer itself, so a backend that has an SDL_Renderer but was never bound segfaults on the first line of text -- the state akgl_render_bind2d() exists to get a host out of. All three are now checked, with AKERR_NULLPOINTER as the draw entry points report, and checked before anything is rasterized rather than after. tests/text.c grows a software renderer with a bound backend and covers all three refusals plus the successful draw, wrapped and unwrapped: src/text.c goes from 58% to 100% line coverage. A made-up SDL_Renderer pointer is not enough to test this -- SDL refuses the bogus handle on its own and the call fails for the wrong reason, which a deleted check survives. Also documents what the tests found: SDL_ttf refuses the empty string, so drawing an empty line is an error while measuring one is not. Filed in TODO.md rather than pinned in the suite. Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>	2026-07-31 12:52:20 -04:00
Andrew Kesterson	ede3452c49	Split akgl_render_bind2d out of akgl_render_init2d ... A host that owns its own window -- an embedded interpreter, which must not create one -- wants the six 2D function pointers without the window, the camera and the property registry that came with them. Until now the only options were to let libakgl own the window or to assign the vtable by hand. akgl_render_bind2d() installs the methods and nothing else, deliberately leaving self->sdl_renderer alone so a caller's own renderer survives it and a caller without one gets a backend that reports AKERR_NULLPOINTER rather than crashing. akgl_render_init2d() calls it once its window exists. tests/renderer.c is new and needs no display: the binding, frame start and end, both draw_texture paths and the draw_mesh stub against a software renderer under the dummy video driver. src/renderer.c goes from 10% line coverage to 56%. Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>	2026-07-31 12:51:58 -04:00
Andrew Kesterson	42b60f725d	Close the test gaps mutation testing found in audio and draw ... A mutation smoke run scored src/audio.c at 50% and src/draw.c at 70% and named three real holes: - Nothing asserted that an unconfigured voice is audible, which is the entire reason the voice table defaults to a square wave at full level instead of a zeroed struct. Deleting the defaults survived. - No envelope test used a non-zero attack and decay together, so the decay measuring from the start of the note rather than from the end of the attack survived. - The circle was only checked at its four axis points, which a mis-signed octant reflection survives. It now checks that every plotted pixel has a mirror in the other three quadrants. Also adds a backend that exists but was never given an SDL_Renderer, which is the state a host is in between allocating one and initializing it; every draw entry point has to report it rather than dereference it. audio 50% -> 75%, draw 70% -> 90%. The survivors are recorded in TODO.md and are honestly untestable from here. Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>	2026-07-31 07:30:18 -04:00
Andrew Kesterson	2a3ca48d8f	Synthesise tones on three voices ... There was no audio API at all: SDL3_mixer was vendored and AKGL_REGISTRY_MUSIC was declared, but nothing opened a mixer, and a mixer plays recordings anyway. BASIC 7.0's SOUND, PLAY, ENVELOPE and VOL describe notes, so this adds a tone generator -- three voices, five waveforms, an ADSR envelope each, mixed to one float stream and fed to an SDL_AudioStream. The voice table works whether or not a device is open. akgl_audio_init connects it to one; a host that owns its own audio pipeline can call akgl_audio_mix instead. That is also what makes the tests deterministic: a device pulls samples on SDL's audio thread whenever it likes, so tests/audio.c mixes by hand and only opens a device in its last test. Phase is computed from the frame counter rather than accumulated, because a float increment of hz/44100 added 44100 times a second walks a held note off pitch. A voice that has never been configured defaults to a square wave at full level, since a zeroed voice would have a sustain of 0.0 and make no sound with no error to explain why. Voices summing past full scale are clamped rather than scaled, so one voice plays at the level it was asked for. Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>	2026-07-31 07:13:18 -04:00