A grid row is a NUL-terminated string, and `putchar_at()` wrote the character,
advanced and terminated -- so `CHAR 1, 40, 1, "#"` on an otherwise empty row
stored the `#` at column 40 with `text[1][0]` still `'\0'`, and the render loop,
which stops at the terminator, drew nothing at all.
The silent nothing is the trap. The write succeeded, the cursor moved, the
stdout mirror showed the character, and only the window stayed blank -- so the
program looked right everywhere except where it mattered. The documented
truncation on the way *back* is fine and is unaffected.
`putchar_at()` now fills the gap with spaces before storing.
**Padded there rather than in `sink_moveto()`**, which TODO.md proposed: this way
`moveto` stays read-only -- the objection that entry raised against its own
suggestion -- and a row is only ever padded when a character actually arrives.
The pad fills from the terminator rather than replacing it. The buffer is not
cleared between rows, so replacing only the terminator would expose the tail of
whatever longer row used to be there: writing "ABCDEFGHIJ", truncating it to
"ABCX", then writing at column 7 must give "ABCX Z" and not "ABCX FGZ".
tests/akgl_backends.c asserts all three cases, and the middle one keeps the
truncation pinned.
TODO.md section 6 item 32, struck.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
0.5.0 gives every exported symbol the akgl_ prefix, which is the first libakgl
release to break this project's source rather than only its ABI. The soname goes
to libakgl.so.0.5 and include/akbasic/akgl.h asserts the floor.
What moved here: akgl_render_bind2d is akgl_render_2d_bind,
akgl_sprite_sheet_coords_for_frame is akgl_spritesheet_coords_for_frame, the
renderer, camera and window globals carry the prefix, and _akgl_renderer and
_akgl_camera are akgl_default_renderer and akgl_default_camera.
The renames were applied by site rather than by pattern, because renderer is also
a parameter name in src/sprite_akgl.c and a struct member throughout
src/frontend_akgl.c -- a substitution would have rewritten both without a word.
That is the same trap upstream describes hitting, and it is worth knowing that
the defect behind the rename was not cosmetic: an exported global called renderer
collided with a test's own variable, the executable's definition preempted the
library's, and every texture load in that suite failed while the suite passed.
0.5.0 also fixes libakgl defect 26, which was one of the two reasons
src/sprite_akgl.c installs its own renderfunc: akgl_actor_render took its
destination height from the sprite's width, drawing a 24x21 Commodore sprite as a
24x24 square. The renderfunc stays, because the other reason has not moved -- an
actor carries one scalar scale and SPRITE has separate x- and y-expand bits --
but the comments and TODO.md deviation 40 no longer claim a defect that is fixed.
Every documentation figure re-renders byte-identical under the new library, which
is what says the sprite and drawing paths did not move underneath them.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
The graphics verbs documented a coordinate transform that did not exist. With
SCALE off a coordinate went straight to akgl_draw_* as a pixel address, so an
800x600 window drew a C128 listing into its corner and left the rest unused --
while the chapter said coordinates were 320x200 and stretching to fit was the
host's business.
akbasic_GraphicsBackend gains a size entry point, require_graphics() asks it
before every verb that draws so a resized window is honoured between two
statements, and 320x200 becomes the fallback for a backend that leaves it NULL.
It is the record's one optional member, so a host written against the old header
keeps the behaviour it had.
SCALE now maps onto the device, and RGR(1)/RGR(2) report the drawing surface so
a program can use a window whose size it did not choose. RGR(0) is BASIC 7.0's
own field, the GRAPHIC mode.
SCALE also mapped xmax onto the width rather than onto the last pixel, so
SCALE 1, 319, 199 followed by DRAW 1, 319, 199 drew nothing at all -- one pixel
past the surface. Fixed in the same line, because it is what makes "SCALE gives
a C128 listing the whole window" true rather than nearly true.
The akgl test renders against a 128x128 target, deliberately smaller than the
old constants: a SCALE still dividing by them misses it entirely rather than
landing somewhere plausible.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Closes groups A, C, D, E, F, H and J of TODO.md section 4, plus RESTORE and
RENUMBER, and closes section 6 -- all seventeen reference defects. Seven of
those turned out to have been fixed or never ported and nobody had written it
down; the audit records the evidence for each.
Two of the seventeen were real. math_plus mutated its left operand when the
operand was mutable, so A# + 1 could modify A#; it was gated on FOR/NEXT
coverage because NEXT relied on the mutation, so tests/for_next.c came first
and NEXT now writes the counter back itself. And the binary operators summed
both numeric fields of their right operand, which no BASIC program can reach
-- that one needed a test written against the value API.
Writing the tests turned up eight defects nobody had listed. Seven are fixed:
IF A = 2 THEN was a parse error; only == worked
IF ... AND ... was a parse error, because a condition parsed as one relation
IF A = 1 OR B = 2 THEN was silently always false, and so was IF A THEN
EXIT before any NEXT restarted the program and exhausted the variable pool
READ never found a DATA line above it, and swallowed the lines between
PRINT 2 + 2 at the prompt was filed as program text instead of answering
a short read discarded its bytes, so COPY produced empty files
every verb taking an argument list said "peek() returned nil token!" on none
The eighth is not fixed and cannot be quietly: a FOR whose step overshoots
runs its body one extra time, and FOR I = 1 TO 1 runs it zero times. The two
errors cancel for a step of 1, which is why neither was noticed. Correcting
them changes the expected output of a checked-in acceptance file, and
tests/reference/README.md forbids editing one to suit this interpreter. It is
tests/for_semantics.c in AKBASIC_KNOWN_FAILING_TESTS, asserting the correct
contract, and TODO.md items 19 and 20.
Sprites are real libakgl actors with a renderfunc of their own, because
akgl_actor_render draws every sprite square and an actor has no per-axis
scale. Both are filed upstream. SPRSAV takes an image file, an SSHAPE handle
or a 63-element integer array -- a string here cannot hold a zero byte.
Verbs that need hardware that does not exist are refused by name with the
reason rather than faked: SYS, HEADER, COLLECT, BACKUP, BOOT, FILTER, and
DIRECTORY, which is refused for a missing libakstdlib wrapper filed upstream.
94 tests in the default build, 93 with SDL, 94 under ASan and UBSan, doxygen
clean. The Go acceptance corpus stayed green throughout.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
0.3.0 closed all ten API gaps this port had filed. The four workarounds go
with them: the CMake block that declared libakgl's vendored dependencies by
hand, the akgl/actor.h include in three files, and the six vtable pointers
assigned by hand in two more, now akgl_render_bind2d().
Two gaps were capabilities rather than inconveniences, and both are now real:
The line editor takes the composed UTF-8 text the ring carries in preference
to the keycode, so shifted characters, keyboard layouts, compose keys and dead
keys all work. A double quote can be typed, which means a BASIC string literal
can be typed -- the sharp end of the old limitation. Letters are no longer
folded to upper case.
SOUND's dir/min/step reach akgl_audio_sweep instead of being refused. dir 3
sweeps once rather than oscillating and TODO.md section 5 says so. A backend
with no sweep still refuses the swept note and plays the held one.
The adaptors now carry an AKGL_VERSION_AT_LEAST(0, 3, 0) floor, verified by
temporarily demanding 0.4.0 and watching it fire.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
src/sink_akgl.c, src/graphics_akgl.c, src/audio_akgl.c and src/input_akgl.c, in
the akbasic_akgl target, which is the only thing here that links SDL.
-DAKBASIC_WITH_AKGL=ON had never been configured in this repository before, and
it now builds and passes.
The sink is what section 3 has been waiting on. Its character grid comes from
akgl_text_measure(font, "A", &w, &h), the direct equivalent of the reference's
font.SizeUTF8("A") and the call that did not exist until 42b60f7. Wrapping is
done on the character grid rather than by handing SDL_ttf a wraplength, because
the cursor has to land somewhere definite: a program that PRINTs a long string
and then PRINTs again expects the second to start on the row after the first
ended, and only the code that placed the characters knows which row that is.
tests/akgl_backends.c draws into a 128x128 software renderer under the dummy
video driver and reads the pixels back -- the pattern deps/libakgl/tests/draw.c
established, which needs no display and no offscreen harness. It asserts the
seam rather than libakgl's own behaviour: a BASIC line in, a lit pixel of the
right colour out.
Four things in libakgl had to be worked around to get here. All four are
commented at their site with "filed upstream" and recorded in TODO.md section 3:
- An embedded libakgl requires SDL, SDL_image, SDL_mixer, SDL_ttf and jansson to
be *installed*. It builds its own vendored copies only when it is top-level,
and they are sitting right there in deps/libakgl/deps. Every lookup is guarded
with if(NOT TARGET ...), so this adds those five subdirectories before
add_subdirectory(deps/libakgl) -- the same trick and the same ordering
requirement akerror::akerror and akstdlib::akstdlib already need.
- akgl/controller.h does not compile on its own: it declares handlers taking an
akgl_Actor * and includes nothing that declares the type.
- There is no way to attach a 2D backend to a renderer you already have.
akgl_render_init2d() installs the vtable but also creates its own window and
writes the camera global, so it belongs to the akgl_game_init() path -- which
is exactly the path an embedding host is not on. The test assigns the six
pointers by hand.
- akgl_text_rendertextat() segfaults on a backend whose vtable is empty; it
reaches through renderer->draw_texture without checking it. Same class of
defect 42b60f7's own commit added a draw test for.
The sink's readline reports end of input rather than reading: a drawn text layer
is not a source of lines, and INPUT through one wants a line editor built on the
keystroke ring. EOF rather than an error is the contract sink.h states, so INPUT
already handles it. That editor is the next piece of work there.
70/70 core ctest with no SDL on the include path, 71/71 with the akgl suite,
clean under -Wall -Wextra, doxygen clean.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
