newppu - process grayscale (and maybe deemph, not sure) on a per-pixel basis to fix the FF1 polygon effect (fixes #529)

1 files changed, 51 insertions, 11 deletions

diff --git a/src/ppu.cpp b/src/ppu.cpp
index 01a03a79..89bd1af9 100644
--- a/src/ppu.cpp
+++ b/src/ppu.cpp
@@ -57,6 +57,7 @@
 

 #define PPU_status  (PPU[2])

 

+#define READPALNOGS(ofs)    (PALRAM[(ofs)])

 #define READPAL(ofs)    (PALRAM[(ofs)] & (GRAYSCALE ? 0x30 : 0xFF))

 #define READUPAL(ofs)   (UPALRAM[(ofs)] & (GRAYSCALE ? 0x30 : 0xFF))

 

@@ -1987,6 +1988,7 @@ void runppu(int x) {
 struct BGData {

 	struct Record {

 		uint8 nt, pecnt, at, pt[2], qtnt;

+		uint8 ppu1[8];

 

 		INLINE void Read() {

 			NTRefreshAddr = RefreshAddr = ppur.get_ntread();

@@ -1998,7 +2000,12 @@ struct BGData {
 			}

 			pecnt = (RefreshAddr & 1) << 3;

 			nt = CALL_PPUREAD(RefreshAddr);

-			runppu(kFetchTime);

+			ppu1[0] = PPU[1];

+			runppu(1);

+			ppu1[1] = PPU[1];

+			runppu(1);

+

+

 

 			RefreshAddr = ppur.get_atread();

 			at = CALL_PPUREAD(RefreshAddr);

@@ -2010,37 +2017,57 @@ struct BGData {
 			at <<= 2;

 			//horizontal scroll clocked at cycle 3 and then

 			//vertical scroll at 251

+			ppu1[2] = PPU[1];

 			runppu(1);

 			if (PPUON) {

 				ppur.increment_hsc();

 				if (ppur.status.cycle == 251)

 					ppur.increment_vs();

 			}

+			ppu1[3] = PPU[1];

 			runppu(1);

 

 			ppur.par = nt;

 			RefreshAddr = ppur.get_ptread();

 			if (PEC586Hack) {

 				pt[0] = CALL_PPUREAD(RefreshAddr | pecnt);

-				runppu(kFetchTime);

+				ppu1[4] = PPU[1];

+				runppu(1);

+				ppu1[5] = PPU[1];

+				runppu(1);

 				pt[1] = CALL_PPUREAD(RefreshAddr | pecnt);

-				runppu(kFetchTime);

+				ppu1[6] = PPU[1];

+				runppu(1);

+				ppu1[7] = PPU[1];

+				runppu(1);

 			} else if (QTAIHack && (qtnt & 0x40)) {

 				pt[0] = *(CHRptr[0] + RefreshAddr);

-				runppu(kFetchTime);

+				ppu1[4] = PPU[1];

+				runppu(1);

+				ppu1[5] = PPU[1];

+				runppu(1);

 				RefreshAddr |= 8;

 				pt[1] = *(CHRptr[0] + RefreshAddr);

-				runppu(kFetchTime);

+				ppu1[6] = PPU[1];

+				runppu(1);

+				ppu1[7] = PPU[1];

+				runppu(1);

 			} else {

 				if (ScreenON)

 					RENDER_LOG(RefreshAddr);

 				pt[0] = CALL_PPUREAD(RefreshAddr);

-				runppu(kFetchTime);

+				ppu1[4] = PPU[1];

+				runppu(1);

+				ppu1[5] = PPU[1];

+				runppu(1);

 				RefreshAddr |= 8;

 				if (ScreenON)

 					RENDER_LOG(RefreshAddr);

 				pt[1] = CALL_PPUREAD(RefreshAddr);

-				runppu(kFetchTime);

+				ppu1[6] = PPU[1];

+				runppu(1);

+				ppu1[7] = PPU[1];

+				runppu(1);

 			}

 		}

 	};

@@ -2216,7 +2243,7 @@ int FCEUX_PPU_Loop(int skip) {
 							pixel = ((pt[0] >> (7 - bgpx)) & 1) | (((pt[1] >> (7 - bgpx)) & 1) << 1) | bgdata.main[bgtile].at;

 						}

 						if (renderbg)

-							pixelcolor = READPAL(pixel);

+							pixelcolor = READPALNOGS(pixel);

 

 						//look for a sprite to be drawn

 						bool havepixel = false;

@@ -2261,12 +2288,25 @@ int FCEUX_PPU_Loop(int skip) {
 								spixel |= (oam[2] & 3) << 2;

 

 								if (rendersprites)

-									pixelcolor = READPAL(0x10 + spixel);

+									pixelcolor = READPALNOGS(0x10 + spixel);

 							}

 						}

 

-						*ptr++ = PaletteAdjustPixel(pixelcolor);

-						*dptr++= PPU[1]>>5; //grab deemph

+						//apply grayscale.. kind of clunky

+						//really we need to read the entire palette instead of just ppu1

+						//this will be needed for special color effects probably (very fine rainbows and whatnot?)

+						//are you allowed to chang the palette mid-line anyway? well you can definitely change the grayscale flag as we know from the FF1 "polygon" effect

+						if(bgdata.main[xt+2].ppu1[xp]&1)

+							pixelcolor &= 0x30;

+

+						//this does deemph stuff inside it.. which is probably wrong...

+						*ptr = PaletteAdjustPixel(pixelcolor);

+

+						ptr++;

+

+						//grab deemph..

+						//I guess this works the same way as the grayscale, ideally?

+						*dptr++ = bgdata.main[xt+2].ppu1[xp]>>5;

 					}

 				}

 			}