diff options
| author | Kartik Agaram <vc@akkartik.com> | 2021-01-15 20:30:07 -0800 |
|---|---|---|
| committer | Kartik Agaram <vc@akkartik.com> | 2021-01-15 20:30:07 -0800 |
| commit | 6e36ce06dd035408d43a6599b75b933a0709cc78 (patch) | |
| tree | b5b90ee59b5387036d311096fed1c96aa588cacb /baremetal/101screen.subx | |
| parent | 20d6be52405130930fde9ca5bb5e95131ba4e659 (diff) | |
| download | mu-6e36ce06dd035408d43a6599b75b933a0709cc78.tar.gz | |
7521 - new plan for tests
It's not really manageable to make the fake screen pixel-oriented. Feels excessive to compare things pixel by pixel when we will mostly be writing text to screen. It'll also make expected screen assertions more difficult to manage. So I'm not sure how to make assertions about pixels for now. Instead we'll introduce fake screens at draw-grapheme.
Diffstat (limited to 'baremetal/101screen.subx')
| -rw-r--r-- | baremetal/101screen.subx | 56 |
1 files changed, 25 insertions, 31 deletions
diff --git a/baremetal/101screen.subx b/baremetal/101screen.subx index 225efeec..5a26a86a 100644 --- a/baremetal/101screen.subx +++ b/baremetal/101screen.subx @@ -1,44 +1,38 @@ # Primitives for screen control. +# +# We need to do this in machine code because Mu doesn't have global variables +# yet (for the start of video memory). == code -pixel: # screen: (addr screen), x: int, y: int, color: int +pixel-on-real-screen: # x: int, y: int, color: int # . prologue 55/push-ebp 89/<- %ebp 4/r32/esp # . save registers 50/push-eax 51/push-ecx - # ecx = screen - 8b/-> *(ebp+8) 1/r32/ecx - 81 7/subop/compare %ecx 0/imm32 - { - 75/jump-if-!= break/disp8 - # bounds checks - 8b/-> *(ebp+0xc) 0/r32/eax - 3d/compare-eax-and 0/imm32 - 7c/jump-if-< $pixel:end/disp8 - 3d/compare-eax-and 0x400/imm32/1024 - 7d/jump-if->= $pixel:end/disp8 - 8b/-> *(ebp+0x10) 0/r32/eax - 3d/compare-eax-and 0/imm32 - 7c/jump-if-< $pixel:end/disp8 - 3d/compare-eax-and 0x300/imm32/768 - 7d/jump-if->= $pixel:end/disp8 - # eax = y*1024 + x - 8b/-> *(ebp+0x10) 0/r32/eax - c1/shift 4/subop/left %eax 0xa/imm8 - 03/add-> *(ebp+0xc) 0/r32/eax - # eax += location of frame buffer - 03/add-> *0x7f28 0/r32/eax - # *eax = color - 8b/-> *(ebp+0x14) 1/r32/ecx - 88/byte<- *eax 1/r32/CL - # return - eb $pixel:end/disp8 - } - # TODO: fake screen -$pixel:end: + # bounds checks + 8b/-> *(ebp+8) 0/r32/eax + 3d/compare-eax-and 0/imm32 + 7c/jump-if-< $pixel-on-real-screen:end/disp8 + 3d/compare-eax-and 0x400/imm32/1024 + 7d/jump-if->= $pixel-on-real-screen:end/disp8 + 8b/-> *(ebp+0xc) 0/r32/eax + 3d/compare-eax-and 0/imm32 + 7c/jump-if-< $pixel-on-real-screen:end/disp8 + 3d/compare-eax-and 0x300/imm32/768 + 7d/jump-if->= $pixel-on-real-screen:end/disp8 + # eax = y*1024 + x + 8b/-> *(ebp+0xc) 0/r32/eax + c1/shift 4/subop/left %eax 0xa/imm8 + 03/add-> *(ebp+8) 0/r32/eax + # eax += location of frame buffer + 03/add-> *0x7f28 0/r32/eax # unsafe + # *eax = color + 8b/-> *(ebp+0x10) 1/r32/ecx + 88/byte<- *eax 1/r32/CL +$pixel-on-real-screen:end: # . restore registers 59/pop-to-ecx 58/pop-to-eax |