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>
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>
