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| author | Kartik K. Agaram <vc@akkartik.com> | 2021-06-12 21:28:43 -0700 |
|---|---|---|
| committer | Kartik K. Agaram <vc@akkartik.com> | 2021-06-12 21:41:02 -0700 |
| commit | b78bff9307de43e7d7f1dc66b4f367b3d3d81449 (patch) | |
| tree | 6d2a04ceada2bc7f72b00ab7fcdb60e34b70d588 /101screen.subx | |
| parent | 0dda332ce36f751b8431fd30cbf7f42501e85800 (diff) | |
| download | mu-b78bff9307de43e7d7f1dc66b4f367b3d3d81449.tar.gz | |
extract a helper to render fonts outside video RAM
Diffstat (limited to '101screen.subx')
| -rw-r--r-- | 101screen.subx | 35 |
1 files changed, 24 insertions, 11 deletions
diff --git a/101screen.subx b/101screen.subx index 2aab293d..22ce490c 100644 --- a/101screen.subx +++ b/101screen.subx @@ -9,30 +9,43 @@ pixel-on-real-screen: # x: int, y: int, color: int # . prologue 55/push-ebp 89/<- %ebp 4/r32/esp + # + (pixel-on-screen-buffer *Video-memory-addr *(ebp+8) *(ebp+0xc) *(ebp+0x10)) +$pixel-on-real-screen:end: + # . epilogue + 89/<- %esp 5/r32/ebp + 5d/pop-to-ebp + c3/return + +# 'buffer' here is not a valid Mu type: a naked address without a length. +pixel-on-screen-buffer: # buffer: (addr byte), x: int, y: int, color: int + # . prologue + 55/push-ebp + 89/<- %ebp 4/r32/esp # . save registers 50/push-eax 51/push-ecx # bounds checks - 8b/-> *(ebp+8) 0/r32/eax + 8b/-> *(ebp+0xc) 0/r32/eax 3d/compare-eax-and 0/imm32 - 7c/jump-if-< $pixel-on-real-screen:end/disp8 + 7c/jump-if-< $pixel-on-screen-buffer:end/disp8 3d/compare-eax-and 0x400/imm32/screen-width=1024 - 7d/jump-if->= $pixel-on-real-screen:end/disp8 - 8b/-> *(ebp+0xc) 0/r32/eax + 7d/jump-if->= $pixel-on-screen-buffer:end/disp8 + 8b/-> *(ebp+0x10) 0/r32/eax 3d/compare-eax-and 0/imm32 - 7c/jump-if-< $pixel-on-real-screen:end/disp8 + 7c/jump-if-< $pixel-on-screen-buffer:end/disp8 3d/compare-eax-and 0x300/imm32/screen-height=768 - 7d/jump-if->= $pixel-on-real-screen:end/disp8 + 7d/jump-if->= $pixel-on-screen-buffer:end/disp8 # eax = y*1024 + x - 8b/-> *(ebp+0xc) 0/r32/eax + 8b/-> *(ebp+0x10) 0/r32/eax c1/shift 4/subop/left %eax 0xa/imm8 - 03/add-> *(ebp+8) 0/r32/eax + 03/add-> *(ebp+0xc) 0/r32/eax # eax += location of frame buffer - 03/add-> *Video-memory-addr 0/r32/eax + 03/add-> *(ebp+8) 0/r32/eax # *eax = color - 8b/-> *(ebp+0x10) 1/r32/ecx + 8b/-> *(ebp+0x14) 1/r32/ecx 88/byte<- *eax 1/r32/CL -$pixel-on-real-screen:end: +$pixel-on-screen-buffer:end: # . restore registers 59/pop-to-ecx 58/pop-to-eax |