GB Video: Improved video timings

This commit is contained in:
Jeffrey Pfau 2016-09-25 19:18:46 -07:00
parent 59e61c31ea
commit c4cfff4581
3 changed files with 10 additions and 7 deletions

View File

@ -21,6 +21,7 @@ Misc:
- All: Only update version info if needed
- FFmpeg: Encoding cleanup
- GB Memory: Initialize RAM pattern for GBC
- GB Video: Improved video timings
0.5.0: (2016-09-19)
Features:

View File

@ -110,7 +110,7 @@ int32_t GBVideoProcessEvents(struct GBVideo* video, int32_t cycles) {
video->p->memory.io[REG_LY] = video->ly;
video->stat = GBRegisterSTATSetLYC(video->stat, lyc == video->ly);
if (video->ly < GB_VIDEO_VERTICAL_PIXELS) {
video->nextMode = GB_VIDEO_MODE_2_LENGTH;
video->nextMode = GB_VIDEO_MODE_2_LENGTH + (video->p->memory.io[REG_SCX] & 7);
video->mode = 2;
if (!GBRegisterSTATIsHblankIRQ(video->stat) && GBRegisterSTATIsOAMIRQ(video->stat)) {
video->p->memory.io[REG_IF] |= (1 << GB_IRQ_LCDSTAT);
@ -142,7 +142,8 @@ int32_t GBVideoProcessEvents(struct GBVideo* video, int32_t cycles) {
if (video->ly == GB_VIDEO_VERTICAL_TOTAL_PIXELS + 1) {
video->ly = 0;
video->p->memory.io[REG_LY] = video->ly;
video->nextMode = GB_VIDEO_MODE_2_LENGTH;
// TODO: Cache SCX & 7 in case it changes during mode 2
video->nextMode = GB_VIDEO_MODE_2_LENGTH + (video->p->memory.io[REG_SCX] & 7);
video->mode = 2;
if (GBRegisterSTATIsOAMIRQ(video->stat)) {
video->p->memory.io[REG_IF] |= (1 << GB_IRQ_LCDSTAT);
@ -175,11 +176,12 @@ int32_t GBVideoProcessEvents(struct GBVideo* video, int32_t cycles) {
video->dotCounter = 0;
video->nextEvent = GB_VIDEO_HORIZONTAL_LENGTH;
video->x = 0;
video->nextMode = GB_VIDEO_MODE_3_LENGTH_BASE + video->objMax * 12;
// TODO: Estimate sprite timings better
video->nextMode = GB_VIDEO_MODE_3_LENGTH_BASE + video->objMax * 11 - (video->p->memory.io[REG_SCX] & 7);
video->mode = 3;
break;
case 3:
video->nextMode = GB_VIDEO_MODE_0_LENGTH_BASE - video->objMax * 12;
video->nextMode = GB_VIDEO_MODE_0_LENGTH_BASE - video->objMax * 11;
video->mode = 0;
if (GBRegisterSTATIsHblankIRQ(video->stat)) {
video->p->memory.io[REG_IF] |= (1 << GB_IRQ_LCDSTAT);

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@ -19,9 +19,9 @@ enum {
GB_VIDEO_VERTICAL_TOTAL_PIXELS = GB_VIDEO_VERTICAL_PIXELS + GB_VIDEO_VBLANK_PIXELS,
// TODO: Figure out exact lengths
GB_VIDEO_MODE_2_LENGTH = 78,
GB_VIDEO_MODE_3_LENGTH_BASE = 160,
GB_VIDEO_MODE_0_LENGTH_BASE = 218,
GB_VIDEO_MODE_2_LENGTH = 83,
GB_VIDEO_MODE_3_LENGTH_BASE = 158,
GB_VIDEO_MODE_0_LENGTH_BASE = 215,
GB_VIDEO_HORIZONTAL_LENGTH = GB_VIDEO_MODE_0_LENGTH_BASE + GB_VIDEO_MODE_2_LENGTH + GB_VIDEO_MODE_3_LENGTH_BASE,