snark13
c71e249a4e
First substantive commit: the entire Sprinter C compiler tree on top of
the bare README+gitignore initial commit.
What's in here:
bin/sprinter-cc — driver script invoking SDCC + linker + mkexe
libc/ — Sprinter-specific libc layer over ESTEX/BIOS
(conio, gfx, io, mem, stdio + headers)
runtime/ — crt0 variants (default/small/banked/minimal)
+ heap + bank trampolines
toolchain/ — mkexe (SprintEXE packer, C + tests)
examples/ — 30 demo programs (gfx, file I/O, env, time, …)
lib/Makefile — builds the libc archive (sprinter.lib)
docs/ — converted Sprinter manuals + asm reference samples
third_party/ — solid-c reference compiler dump + sdcc setup script
release_docs/ — packaging / release notes
gitignore overhaul:
• Drop dangerous blanket patterns: *.asm (would hide docs/samples/*.asm)
and *.exe (case-insensitive match was hiding third_party/solid-c/*.EXE
on macOS APFS). Replaced with examples/*/*.{asm,exe,…} and lib/*.lib.
• Restore tracking of toolchain/mkexe/tests/{one,big}.bin — those are
INPUT fixtures, not build outputs.
• Collapse the duplicated SDCC/C/Sdcc sections into one section per
concern (build outputs / vendored / OS-junk).
• Add .sprinter-cc-*/, build/ (catches lib/build/ too), .claude/.
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
64 lines
1.8 KiB
C
64 lines
1.8 KiB
C
/*
|
||
* gfx_font.c — bitmap-font management shared by the 256- and 16-colour
|
||
* text renderers.
|
||
*
|
||
* Format (ZX-Spectrum-compatible): 256 glyphs × 8 rows × 1 byte = 2 KB,
|
||
* INTERLEAVED row-major —
|
||
* offset = row * 256 + char_code
|
||
* so row 0 of every glyph occupies bytes 0x000..0x0FF, row 1 occupies
|
||
* 0x100..0x1FF, etc. Each row byte is MSB-first (bit 7 = leftmost px).
|
||
*
|
||
* The default source is BIOS WIN_GET_ZG (fn 0xB8) — the active system
|
||
* character generator. Programs may override with gfx_set_font().
|
||
*
|
||
* Lazy initialisation: gfx_text_256.c / gfx_text_16.c call _gfx_font_ensure
|
||
* on first use so a pure-graphics program doesn't pay the BIOS call.
|
||
*
|
||
* The font pointer and the buffer are exported to the two text renderers
|
||
* via _gfx_font_ptr (extern), which always points at valid data once
|
||
* _gfx_font_ensure has been called.
|
||
*/
|
||
|
||
#include <gfx.h>
|
||
#include <stdint.h>
|
||
|
||
#define FONT_BYTES 2048
|
||
|
||
static uint8_t _gfx_font_buf[FONT_BYTES];
|
||
const uint8_t *_gfx_font_ptr = _gfx_font_buf;
|
||
static uint8_t _gfx_font_loaded = 0;
|
||
|
||
/* BIOS WIN_GET_ZG (0xB8): DE = destination, returns 2 KB. */
|
||
static void bios_get_zg(uint8_t *dest) __naked
|
||
{
|
||
(void)dest;
|
||
__asm
|
||
push ix ; BIOS clobbers IX
|
||
ex de, hl ; DE = dest (HL was arg)
|
||
xor a ; font 0 (default)
|
||
ld c, #0xB8
|
||
rst #0x08
|
||
pop ix
|
||
ret
|
||
__endasm;
|
||
}
|
||
|
||
void gfx_load_default_font(void)
|
||
{
|
||
bios_get_zg(_gfx_font_buf);
|
||
_gfx_font_ptr = _gfx_font_buf;
|
||
_gfx_font_loaded = 1;
|
||
}
|
||
|
||
void gfx_set_font(const uint8_t *font)
|
||
{
|
||
_gfx_font_ptr = font;
|
||
_gfx_font_loaded = 1;
|
||
}
|
||
|
||
/* Called from text renderers — loads the default font on first use. */
|
||
void _gfx_font_ensure(void)
|
||
{
|
||
if (!_gfx_font_loaded) gfx_load_default_font();
|
||
}
|