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add support for writing to VCount. incl. fucked-up display and altering framerate accordingly.

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This commit is contained in:
StapleButter
2017-05-10 02:21:02 +02:00
parent 63e15d2480
commit f54f54fb7e
6 changed files with 72 additions and 36 deletions
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60
src/GPU.cpp
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@ -30,6 +30,8 @@ namespace GPU
#define FRAME_CYCLES (LINE_CYCLES * 263)
u16 VCount;
u32 NextVCount;
u16 TotalScanlines;
u16 DispStat[2], VMatch[2];
@ -50,9 +52,6 @@ u8* VRAM[9] = {VRAM_A, VRAM_B, VRAM_C, VRAM_D, VRAM_E, VRAM_F, VRAM_G, VRAM_H, V
u8 VRAMCNT[9];
u8 VRAMSTAT;
//u32 VRAM_Base[9];
//u32 VRAM_Mask[9];
u32 VRAMMap_LCDC;
u32 VRAMMap_ABG[0x20];
@ -95,6 +94,8 @@ void DeInit()
void Reset()
{
VCount = 0;
NextVCount = -1;
TotalScanlines = 0;
DispStat[0] = 0;
DispStat[1] = 0;
@ -607,6 +608,7 @@ void DisplaySwap(u32 val)
void StartFrame()
{
TotalScanlines = 0;
StartScanline(0);
}
@ -615,23 +617,37 @@ void StartHBlank(u32 line)
DispStat[0] |= (1<<1);
DispStat[1] |= (1<<1);
if (line < 192) NDS::CheckDMAs(0, 0x02);
if (VCount < 192) NDS::CheckDMAs(0, 0x02);
if (DispStat[0] & (1<<4)) NDS::SetIRQ(0, NDS::IRQ_HBlank);
if (DispStat[1] & (1<<4)) NDS::SetIRQ(1, NDS::IRQ_HBlank);
if (line < 262)
if (VCount < 262)
NDS::ScheduleEvent(NDS::Event_LCD, true, (LINE_CYCLES - HBLANK_CYCLES), StartScanline, line+1);
else
NDS::ScheduleEvent(NDS::Event_LCD, true, (LINE_CYCLES - HBLANK_CYCLES), FinishFrame, line+1);
}
void FinishFrame(u32 lines)
{
TotalScanlines = lines;
}
void StartScanline(u32 line)
{
VCount = line;
if (line == 0)
VCount = 0;
else if (NextVCount != -1)
VCount = NextVCount;
else
VCount++;
NextVCount = -1;
DispStat[0] &= ~(1<<1);
DispStat[1] &= ~(1<<1);
if (line == VMatch[0])
if (VCount == VMatch[0])
{
DispStat[0] |= (1<<2);
@ -640,7 +656,7 @@ void StartScanline(u32 line)
else
DispStat[0] &= ~(1<<2);
if (line == VMatch[1])
if (VCount == VMatch[1])
{
DispStat[1] |= (1<<2);
@ -649,12 +665,12 @@ void StartScanline(u32 line)
else
DispStat[1] &= ~(1<<2);
GPU2D_A->CheckWindows(line);
GPU2D_B->CheckWindows(line);
GPU2D_A->CheckWindows(VCount);
GPU2D_B->CheckWindows(VCount);
if (line >= 2 && line < 194)
if (VCount >= 2 && VCount < 194)
NDS::CheckDMAs(0, 0x03);
else if (line == 194)
else if (VCount == 194)
NDS::StopDMAs(0, 0x03);
if (line < 192)
@ -664,7 +680,8 @@ void StartScanline(u32 line)
// properly would be too much trouble given barely anything
// uses FIFO display
// (TODO, eventually: emulate it properly)
NDS::CheckDMAs(0, 0x04);
if (VCount < 192)
NDS::CheckDMAs(0, 0x04);
if (line == 0)
{
@ -676,7 +693,8 @@ void StartScanline(u32 line)
GPU2D_A->DrawScanline(line);
GPU2D_B->DrawScanline(line);
}
else if (line == 262)
if (VCount == 262)
{
// frame end
@ -685,7 +703,7 @@ void StartScanline(u32 line)
}
else
{
if (line == 192)
if (VCount == 192)
{
// VBlank
DispStat[0] |= (1<<0);
@ -703,7 +721,7 @@ void StartScanline(u32 line)
GPU2D_B->VBlank();
GPU3D::VBlank();
}
else if (line == 215)
else if (VCount == 215)
{
GPU3D::VCount215();
}
@ -722,4 +740,14 @@ void SetDispStat(u32 cpu, u16 val)
VMatch[cpu] = (val >> 8) | ((val & 0x80) << 1);
}
void SetVCount(u16 val)
{
// VCount write is delayed until the next scanline
// TODO: how does the 3D engine react to VCount writes while it's rendering?
// TODO: also check the various DMA types that can be involved
NextVCount = val;
}
}