diff options
Diffstat (limited to 'src/battle/anim')
| -rw-r--r-- | src/battle/anim/water.c | 83 |
1 files changed, 12 insertions, 71 deletions
diff --git a/src/battle/anim/water.c b/src/battle/anim/water.c index d3e037272..135ed43cb 100644 --- a/src/battle/anim/water.c +++ b/src/battle/anim/water.c @@ -684,36 +684,24 @@ void sub_80D3D68(u8 taskId) case 0: for (i = 0; i < task->data[4]; i++) { - /* - It would be odd for the scanline buffers to follow ASM literal - and be initialized in reverse. Experimentation based upon how - compilers in general load variables and pointers showed that - they were initialized this way. - - foo = bar = baz -> foo = (bar = baz) - */ - gScanlineEffectRegBuffers[0][i] = - gScanlineEffectRegBuffers[1][i] = task->data[2]; + /* variable initialization isn't literal to ASM */ + gScanlineEffectRegBuffers[0][i] = gScanlineEffectRegBuffers[1][i] = task->data[2]; } for (i = task->data[4]; i < task->data[5]; i++) { - gScanlineEffectRegBuffers[0][i] = - gScanlineEffectRegBuffers[1][i] = task->data[1]; + gScanlineEffectRegBuffers[0][i] = gScanlineEffectRegBuffers[1][i] = task->data[1]; } for (i = task->data[5]; i < 160; i++) { - gScanlineEffectRegBuffers[0][i] = - gScanlineEffectRegBuffers[1][i] = task->data[2]; + gScanlineEffectRegBuffers[0][i] = gScanlineEffectRegBuffers[1][i] = task->data[2]; } if (task->data[4] == 0) { - gScanlineEffectRegBuffers[0][i] = - gScanlineEffectRegBuffers[1][i] = task->data[1]; + gScanlineEffectRegBuffers[0][i] = gScanlineEffectRegBuffers[1][i] = task->data[1]; } else { - gScanlineEffectRegBuffers[0][i] = - gScanlineEffectRegBuffers[1][i] = task->data[2]; + gScanlineEffectRegBuffers[0][i] = gScanlineEffectRegBuffers[1][i] = task->data[2]; } params.dmaDest = (vu16 *)REG_ADDR_BLDALPHA; params.dmaControl = SCANLINE_EFFECT_DMACNT_16BIT; @@ -1313,63 +1301,16 @@ void sub_80D4D64(struct Sprite *sprite, s32 xDiff, s32 yDiff) s16 randomSomethingY; something = sprite->data[0] / 2; - // Without the weird hack? you are about to see below, regalloc acts funny here... + // regalloc acts strange here... combinedX = sprite->pos1.x + sprite->pos2.x; combinedY = sprite->pos1.y + sprite->pos2.y; - /* - Then goes back to normal at this exact point. Something must have existed here - that lined up regalloc properly. Whatever it was, it's not the traditional if - (0) or do {} while (0). Nor is it localvar++--. It's something completely obscene. - - Upon random experiments, there was an observation about how parameters affected - regalloc in ways more bizarre than local variables. xDiff++; xDiff--; had actually - changed the regalloc immensely: - - mov r2, #0x2e - ldrsh r1, [r0, r2] - lsr r2, r1, #0x1f - add r1, r1, r2 - lsl r1, r1, #0xf - lsr r1, r1, #0x10 - str r1, [sp] - - ldrh r3, [r0, #0x24] - mov r8, r3 - ldrh r1, [r0, #0x20] - add r8, r8, r1 - mov r2, r8 - lsl r2, r2, #0x10 - lsr r2, r2, #0x10 - mov r8, r2 - - ldrh r6, [r0, #0x26] - ldrh r0, [r0, #0x22] - add r6, r6, r0 - lsl r6, r6, #0x10 - lsr r6, r6, #0x10 - - compared to doing the same to a local variable, where there was no change at - all. It's more similar to the actual ASM, but not quite, telling us that - something did indeed poke xDiff, but not through mathematical statements. - The only ideal possibility to turn to in this situation now would be an if - statement. - */ - if (xDiff) + + // ...then goes back to normal right here. + // Nothing but this appears to reproduce the behavior. + if (xDiff) // yDiff works too, but not sprite. { - /* - if (xDiff) by itself won't match, so something needs to - be in here. - - Virtually nothing what you are about to see is in the - assembly, you just have to to come up a strange variety - of compile time scenarios, question reality, and see if - something happens. - */ - // This absolutely needs to be a negation of some kind. - u8 unk = -unk; // ...this is what I came up with. It matches. - // i = -i; // This matches too. It might just work on any uninitialized. + u8 unk = -unk; // this can be any sort of negation } - // by the way, yDiff works for the if case too, but oddly not sprite. randomSomethingY = yDiff + (Random() % 10) - 5; randomSomethingX = -xDiff + (Random() % 10) - 5; |