Commit Graph

85 Commits

Author SHA1 Message Date
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
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
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
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
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
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
06f8e03a03 Give the tilemap types struct tags so they can be forward-declared
`typedef struct { ... } akgl_Tilemap;` declares no struct tag, so
`struct akgl_Tilemap` does not exist and no header can forward-declare it. That
is fine while every consumer includes tilemap.h, and it is a blocker the moment
a leaf header needs to name the type without pulling it in -- which the coming
collision header does, since tilemap.h reaches physics.h and a cycle forms
otherwise.

All four types in the file get a tag rather than just akgl_Tilemap: they are
siblings declared the same way in the same header, and tagging one of four is
the kind of inconsistency that makes the next reader wonder what is special
about it.

Layout-identical and no behaviour: a tag names a type, it does not change one.
Full suite, reindent and doxygen unchanged.

sprite.h and iterator.h declare their types the same way and are deliberately
left alone; nothing needs to forward-declare them yet.

Co-Authored-By: Claude Code <noreply@anthropic.com>
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
2026-08-01 23:13:17 -04:00
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
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
cc757ab578 Fix the two Doxygen errors that were failing the docs build
`Doxyfile` sets `WARN_AS_ERROR = FAIL_ON_WARNINGS` and CI builds the docs as a
step of `cmake_build`, so both of these failed the job:

- `akgl_character_initialize` documented `@param basechar` for a parameter the
  declaration spells `obj`. This is exactly the mismatch AGENTS.md warns about
  under Naming Conventions -- "parameter names must match between the
  declaration and the definition, Doxygen publishes the header spelling" -- and
  it cost two errors, one for the argument that does not exist and one for the
  argument left undocumented.
- `require_at_eof` asked for an explicit link to `#AKERR_EOF`. That symbol is
  libakerror's and `Doxyfile`'s INPUT is `include/akgl src`, so the link can
  never resolve. Backticks say the same thing to a reader without asking
  Doxygen to find a page it does not have.

`doxygen Doxyfile` now exits 0 with no diagnostics.

Co-Authored-By: Claude Code <noreply@anthropic.com>
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
2026-08-01 20:57:26 -04:00
e4aa6a5084 Take libakerror 2.0.1 and drop the workaround it makes obsolete
Some checks failed
libakgl CI Build / cmake_build (push) Failing after 20s
libakgl CI Build / performance (push) Failing after 19s
libakgl CI Build / memory_check (push) Failing after 15s
libakgl CI Build / mutation_test (push) Failing after 17s
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
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
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
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
b0a4e36ded Regenerate the controller database with the fixed generator
A deliberate standalone commit, as AGENTS.md asks for this file.

Content is byte-identical -- 2255 mappings, not one changed -- which is the
point: it demonstrates the rewritten mkcontrollermappings.sh produces exactly
what the old one did on the success path. The only differences are the $(date)
stamp and the include guard, which is _AKGL_SDL_GAMECONTROLLERDB_H_ now so it
matches every other header in include/akgl/.

That rename was made in the generator rather than by hand, per the rule about
generated files, and the tracked copy carries it so the next regeneration shows
no spurious diff.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
2026-08-01 07:34:50 -04:00
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
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
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
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
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
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
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
5dfa49482c Guard the add_test shadow on being top-level again
CMake chains command overrides one level deep: a second override rebinds
_add_test to the first and the builtin becomes unreachable to everyone. So two
projects in one tree cannot both shadow add_test, and akbasic has to shadow it
first for libakerror and libakstdlib -- which left its own registrations
recursing to CMake's depth limit.

The unconditional shadow arrived with the vendored-dependency fix in 18399f2.
That half stays; only the guard comes back.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
2026-07-31 16:54:48 -04:00
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
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
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
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
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
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
f0858b0d38 Document what the functions actually do instead of that they can fail
The Doxygen comments were generated from the declarations, so 217 @throws
lines across 21 headers read "When the corresponding validation or operation
fails" and told a caller nothing beyond the status name. The @param lines were
the same shape: every output was "Output destination populated by the
function", every instance "Object to initialize, inspect, or modify".

Rewritten against the implementations, following the pattern libakstdlib
already uses:

- @throws names the condition. akgl_sprite_load_json separated AKERR_KEY
  (absent) from AKERR_TYPE (present, wrong type) from AKERR_OUTOFBOUNDS
  (filename too long, or array indexed past its end), and gained AKGL_ERR_SDL
  and AKGL_ERR_HEAP, which it raises and never declared.
- Parameters say whether they are required, what a NULL means, and what is
  written on a failure path. Where an argument is not checked, the doc says so:
  akgl_heap_next_actor's dest is a crash on NULL, not an error, and
  akgl_render_2d_frame_start dereferences self before testing it.
- The conventions move up to the file blocks so the per-function docs stay
  short. json_helpers.h states once that absence is an error here and that
  json_t * results are borrowed; heap.h explains the pool model and the
  acquire asymmetry; physics.h carries the thrust/environmental/velocity table.
- Struct fields, enum values, macros and exported globals are documented,
  including the dead ones - sprite_w/sprite_h, movetimer, p_scale and
  timer_gravity are read by nothing, and say so.

Also fixes ten comments in error.h and audio.h that opened with /** rather
than /**<, so Doxygen attached them to the following entity and rendered the
text as part of the macro's value. Verified against the generated HTML.

Comments only - no declaration changed. Doxygen builds clean under
WARN_AS_ERROR, scripts/reindent.sh --check passes, 19/19 suites pass.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
2026-07-31 11:23:15 -04:00
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
dba0f8db89 Draw shapes immediately against a renderer
BASIC 7.0's graphics verbs -- DRAW, BOX, CIRCLE, PAINT, SSHAPE and GSHAPE -- all
plot against the current screen right now rather than adding to a scene, and
draw.h had exactly one function in it. This adds akgl_draw_point, _line, _rect,
_filled_rect, _circle, _flood_fill, _copy_region and _paste_region, each taking
the akgl_RenderBackend the host already initialized.

Color is an argument rather than a current-color global, so there is no second
copy of state to disagree with the caller's own, and each call restores the
renderer's draw color when it is done. SDL3 has no circle and no flood fill: the
circle is a midpoint circle, and the fill reads the target back, walks the
region with a fixed 4096-entry span stack, and blits back only the bounding box
of what changed. Exhausting that stack reports AKERR_OUTOFBOUNDS and says in the
header that the region is left partially filled.

tests/draw.c draws into a 64x64 software renderer under the dummy video driver
and reads the pixels back, so it needs no display and no offscreen harness.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
2026-07-31 07:05:36 -04:00
1ddc64010a Let a caller take keystrokes without owning the event loop
akbasic's GET and GETKEY ask "is there a keystroke waiting, yes or no" and must
not require the interpreter to pump SDL events itself. akgl_controller_poll_key
drains one key per call from a fixed 32-entry ring that
akgl_controller_handle_event fills, so the host keeps pumping and the embedded
interpreter reads at its own pace. akgl_controller_flush_keys discards a
backlog.

The recording happens before the control-map scan, not after: that scan returns
as soon as a binding claims the event, so recording afterwards would have
dropped exactly the keys a game also acts on. A full buffer refuses the newest
keystroke rather than overwriting the oldest, so a caller reading a line gets
what was typed first.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
2026-07-31 06:57:50 -04:00
17e6e04c79 Measure rendered text without drawing it
akbasic needs the advance width of one character cell to build a terminal-style
text surface, and the wrapped size to know where a string crosses the right
margin. akgl_text_measure and akgl_text_measure_wrapped report both over
TTF_GetStringSize and TTF_GetStringSizeWrapped; neither needs a renderer, so
this half of the text subsystem is testable without the offscreen harness.

A negative wrap length is refused with AKERR_OUTOFBOUNDS: SDL_ttf reads it as a
very large unsigned width and quietly stops wrapping, which would return a
measurement that is wrong rather than an error the caller can see.

Also fixes akgl_text_loadfont, which checked name twice and passed an unchecked
filepath to TTF_OpenFont (TODO item 39).

The fixture font is a 10 KB monospaced ASCII subset of Liberation Mono, renamed
because "Liberation" is a Reserved Font Name; see
tests/assets/akgl_test_mono.LICENSE.txt. Monospaced so the suite can assert
width("AAAA") == 4 * width("A") rather than hardcode glyph metrics.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
2026-07-31 06:55:25 -04:00
c5a7b6053d Derive the library version from one place and give the .so a soname
The version was written down twice and agreed with itself by luck.
AKGL_VERSION was hand-maintained in include/akgl/game.h, and nothing
connected it to the build, which had no version at all:

- project() declared no VERSION, so the @PROJECT_VERSION@ substitution
  in akgl.pc.in expanded to nothing and every installed akgl.pc shipped
  an empty Version field. pkg-config --modversion returned "" and
  --atleast-version could not work at all.
- libakgl.so had no VERSION or SOVERSION, so there was no soname and no
  symlink chain. A stale libakgl could be paired with new headers
  silently, which is the failure libakerror added its own soname to
  prevent.
- MY_LIBRARY_VERSION at CMakeLists.txt:288 was never set anywhere. It
  built main_lib_dest as "lib/akgl-", and main_lib_dest was then never
  read. Dead line, removed.

project(akgl VERSION 0.1.0) is now the only place the number appears. It
drives the generated include/akgl/version.h, the shared library VERSION
and SOVERSION, and the Version field in akgl.pc. Held at 0.1.0 to match
the constant it replaces, so akgl_game_load_versioncmp still compares
savegames against the same value.

include/akgl/version.h is generated by configure_file from version.h.in
and publishes AKGL_VERSION, AKGL_VERSION_MAJOR/MINOR/PATCH and
AKGL_VERSION_AT_LEAST(major, minor, patch). That macro is the point:
libakstdlib could not write that test against libakerror, which
publishes no version macro, and had to feature-test on
AKERR_FIRST_CONSUMER_STATUS instead. game.h now includes the generated
header rather than defining the version itself, so consumers see
AKGL_VERSION exactly where they saw it before.

While the major version is 0 the soname carries major.minor, giving
libakgl.so.0.1. A plain SOVERSION 0 would assert that 0.1.0 and 0.2.0
are ABI-interchangeable, and they are not -- the preceding commit alone
added akgl_error_init. At 1.0.0 the soname becomes the major alone,
matching libakerror.

akgl_version() in src/version.c reports the version of the libakgl that
is actually linked, where AKGL_VERSION reports what the caller compiled
against. Comparing the two is the only way to catch a stale shared
library on the loader path; the macro alone cannot see it. It returns a
string rather than an akerr_ErrorContext * because it cannot fail, for
the same reason akerr_name_for_status does.

Add tests/version.c: the string and the numeric components must describe
one version, the linked library must agree with the headers, and
AKGL_VERSION_AT_LEAST must order correctly at the major, minor and patch
boundaries. Verified out of band that bumping project() to 1.2.3 moves
version.h, akgl.pc and the soname together, and that an install produces
the libakgl.so -> .so.0.1 -> .so.0.1.0 chain with SONAME libakgl.so.0.1.

Also ignore include/akgl/version.h. include/ precedes the build tree on
the include path, so a stray copy there would shadow the generated one
and pin every consumer to whatever version it was generated at.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
2026-07-30 22:36:50 -04:00
9b124f2e27 Migrate to the libakerror 1.0.0 status registry
libakerror 1.0.0 replaced the consumer-sized status-name array with a
private registry and made status-code ownership explicit and enforced.
AKERR_MAX_ERR_VALUE and __AKERR_ERROR_NAMES are gone, and the registry
entry points raise akerr_ErrorContext * instead of returning int. See
deps/libakerror/UPGRADING.md.

The break was not only source-level. libakgl's codes sat at
AKERR_LAST_ERRNO_VALUE + 18 through + 22, and 1.0.0 claimed exactly
those five offsets for its own AKERR_STATUS_* registry codes, so every
AKGL_ERR_* was aliasing a libakerror status. HANDLE(e,
AKGL_ERR_LOGICINTERRUPT) at physics.c:222 would have swallowed a
foreign-name refusal.

- Move the band to AKERR_FIRST_CONSUMER_STATUS (256) as fixed offsets,
  so a libc that grows an errno cannot move the codes, and add
  AKGL_ERR_OWNER, AKGL_ERR_LIMIT and AKGL_ERR_COUNT to describe it.
- Reserve the range and register the names through the owned entry
  points, PASS-ing each: these are AKERR_NOIGNORE, and the old
  akerr_name_for_status calls discarded failure silently.
- Drop the AKERR_MAX_ERR_VALUE=256 compile definition.
- Guard on AKERR_FIRST_CONSUMER_STATUS in include/akgl/error.h, which
  now includes <akerror.h> so the guard is reliable. The embedded build
  is fine, but the find_package path can pick up a stale installed
  header, and 1.0.0 has an soname, so that pairing is an ABI mismatch
  rather than a compile problem. Same guard libakstdlib already carries.

Registration also moves out of akgl_heap_init into a new akgl_error_init
in src/error.c. It was in the heap pool's initializer only because that
was the first thing akgl_game_init called, and the upgrade turned five
fire-and-forget name calls into a library-wide ownership claim that can
fail. That placement was hiding a defect: game.c raises AKGL_ERR_SDL
when SDL_CreateMutex fails, five lines before akgl_heap_init ran, so the
earliest error path in the library was guaranteed to print "Unknown
Error". akgl_error_init is now the first statement in akgl_game_init.

Callers that drive subsystems directly must call akgl_error_init first;
it is idempotent, so ordering it precisely is not required. The eleven
test suites that relied on akgl_heap_init to name their statuses now
call it explicitly, or their failure messages would have degraded to
"Unknown Error".

Add tests/error.c: assert every code reads back its registered name,
that the name table and AKGL_ERR_COUNT agree, that a foreign owner is
refused with AKERR_STATUS_NAME_FOREIGN and AKERR_STATUS_RANGE_OVERLAP,
and that repeating the init is a no-op. That last one is a live
constraint, not a triviality -- libakerror treats only an identical
reservation as a repeat, so a subset or superset raises.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
2026-07-30 22:20:28 -04:00
28bde4176d Reindent all C sources to the canonical stroustrup style
Mechanical whitespace-only change across src/, include/, tests/, and
util/, applied with scripts/reindent.sh. No behavioral change.

Most files already conformed. The genuine outliers indented at 2 columns
(json_helpers.c, util.c from akgl_rectangle_points onward, assets.c,
staticstring.c, akgl_actor_add_child, util.h, staticstring.h) or used
spaces where the canonical form is a tab (draw.c). cc-mode also re-aligns
line-continuation backslashes in multi-line macros to its default
c-backslash-column, which is required for the tree to be a fixed point of
the indenter.

Verified whitespace-only: `git diff -w` over this change is empty apart
from three trailing blank lines removed at EOF in src/heap.c,
src/registry.c, and tests/tilemap.c. The build produces no new errors and
ctest is unchanged at 13/14, with `character` still the one intentional
failure.

The tree is now a fixed point of `scripts/reindent.sh --check`.

include/akgl/SDL_GameControllerDB.h is generated and excluded.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
2026-07-30 18:17:37 -04:00
549b27d3eb Document the libakgl API with Doxygen
Add file, structure, global, and function documentation across all libakgl-owned headers and sources, including parameter contracts and likely AKERR/AKGL_ERR exceptions. Add a strict Doxyfile and build the generated API documentation in Gitea CI with warnings treated as failures.

Co-authored-by: Codex (GPT-5) <noreply@openai.com>
2026-07-30 01:10:31 -04:00
cf9ebb206f Repair embedded dependency build and test setup
Isolate vendored test registration, namespace project error codes, and update dependency revisions. Fix mutable sprite path handling, out-of-tree fixtures, and charviewer initialization while documenting the outstanding character-to-sprite refcount bug.

Co-authored-by: Codex (GPT-5) <noreply@openai.com>
2026-07-29 18:17:08 -04:00
652ee4cdf3 Tilemaps can now load their own physics engines from map properties. The gravity for the arcade simulation is acting a little funny when populated from the map properties. 2026-06-02 17:11:16 -04:00
9fed59c4c8 Abstract the global renderer, physics, camera and gamemap objects behind a pointer, so you can swap in and out different ones as needed 2026-06-02 13:15:26 -04:00
941eeb2493 Got the physics system applying gravity and drag correctly. (Mostly? Seems like it? Seems good.) 2026-05-26 16:45:04 -04:00
314ce5e10d Physics simulation engine implemented, basic cases (null and 2d SideScroller) works 2026-05-26 10:36:31 -04:00
d87c5d2c20 More rendering subsystem breakout, added a physics subsystem, everything now fires from akgl_game_update() for the user 2026-05-25 21:29:18 -04:00
6314ad7f26 Start abstracting the rendering backend away to make it easier to switch to GPU rendering later 2026-05-24 21:59:29 -04:00
8f613397d6 Loading sprites and tiles both work correctly with relative paths, now using akgl_path_relative* helpers 2026-05-24 19:57:57 -04:00
980bbc56fb Fixed loading of tilesets and images from tilemaps to correctly use relative paths. 2026-05-24 10:28:35 -04:00
e3edd5b855 Add a method that automatically opens gamepads so they will send events 2026-05-21 21:43:51 -04:00
f695a035c8 Add a low FPS callback to aid in debugging, and fix a huge memory leak in akgl_text_rendertextat 2026-05-15 11:07:31 -04:00
73b1a4cab0 Make perspective scale work more explicitly from properties 2026-05-13 23:36:49 -04:00