Andrew Kesterson
9b9dd09c5a
Groups G, I and E are unblocked but cannot be written yet: the core library is free of SDL and builds with no libakgl present, so a graphics verb cannot call akgl_draw_* and a sound verb cannot call akgl_audio_*. This adds what they call instead. Three records of function pointers -- akbasic_GraphicsBackend, _AudioBackend and _InputBackend -- in the same shape as akbasic_TextSink, and the same shape libakgl uses for akgl_RenderBackend. akbasic_runtime_set_devices() attaches any subset; all three may be NULL and that is the standalone driver's normal state, so a runtime with no backends still comes up and still prints. A verb that needs one it was not given raises the new AKBASIC_ERR_DEVICE rather than dereferencing a NULL vtable. Two decisions worth stating. The graphics record has no circle entry point: BASIC 7.0's CIRCLE takes two radii, an arc range, a rotation and a degree increment, which makes it a polygon by definition, so it will be built from line calls rather than from akgl_draw_circle. And coordinates are double rather than an integer pixel address, because SCALE makes them fractional and rounding at each verb rather than once at the backend accumulates drift along a polyline. akbasic_runtime_settime() is how SOUND, PLAY and TEMPO get a clock without the library reading one. Section 1.6 forbids blocking or owning a loop, so the caller that owns the frame owns the time -- which is what libakgl already does, since akgl_actor_logic_changeframe takes curtimems as an argument. Left unset it is zero and every duration expires immediately: audible, but never a hang. AKBASIC_ERR_LAST is a sentinel rather than a status, so tests/error_codes.c walks every code looking for an unnamed one without anybody remembering to widen the loop when a code is added. tests/mockdevice.h records every backend call as a formatted line. The graphics and audio verbs emit nothing a golden file can compare, so that log is where their assertions have to live -- and since it needs no SDL, the whole of groups G, I and E stays testable in the default build. 62/62 ctest, clean under -Wall -Wextra, doxygen clean. Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
12 KiB
12 KiB