Palette mirror fix (#81)

* ppuview and memview fixes for palette mirroring
* New PPU $2001 rendering off palette mirroring fixed

src/debug.h

@@ -113,7 +113,7 @@ extern void IncrementInstructionsCounters();
 
 //internal variables that debuggers will want access to
 extern uint8 *vnapage[4],*VPage[8];
-extern uint8 PPU[4],PALRAM[0x20],SPRAM[0x100],VRAMBuffer,PPUGenLatch,XOffset;
+extern uint8 PPU[4],PALRAM[0x20],UPALRAM[3],SPRAM[0x100],VRAMBuffer,PPUGenLatch,XOffset;
 extern uint32 FCEUPPU_PeekAddress();
 extern uint8 READPAL_MOTHEROFALL(uint32 A);
 extern int numWPs;

src/drivers/win/memview.cpp

@@ -147,6 +147,7 @@ void FindNext();
 void OpenFindDialog();
 static int GetFileData(uint32 offset);
 static int WriteFileData(uint32 offset,int data);
+static void PalettePoke(uint32 addr, uint8 data);
 
 
 HWND hMemView, hMemFind;
@@ -1013,7 +1014,7 @@ void InputData(char *input){
 			if((addr >= 0x2000) && (addr < 0x3F00))
 				vnapage[(addr>>10)&0x3][addr&0x3FF] = data[i]; //todo: this causes 0x3000-0x3f00 to mirror 0x2000-0x2f00, is this correct?
 			if((addr >= 0x3F00) && (addr < 0x3FFF))
-				PALRAM[addr&0x1F] = data[i];
+				PalettePoke(addr,data[i]);
 		} else if (EditingMode == MODE_NES_OAM)
 		{
 			addr &= 0xFF;
@@ -1049,7 +1050,7 @@ if(EditingMode == MODE_NES_PPU){
 addr &= 0x3FFF;
 if(addr < 0x2000)VPage[addr>>10][addr] = data; //todo: detect if this is vrom and turn it red if so
 if((addr > 0x2000) && (addr < 0x3F00))vnapage[(addr>>10)&0x3][addr&0x3FF] = data; //todo: this causes 0x3000-0x3f00 to mirror 0x2000-0x2f00, is this correct?
-if((addr > 0x3F00) && (addr < 0x3FFF))PALRAM[addr&0x1F] = data;
+if((addr > 0x3F00) && (addr < 0x3FFF)) PalettePoke(addr,data);
 }
 if(EditingMode == MODE_NES_FILE)ApplyPatch(addr,1,(uint8 *)&data);
 CursorStartAddy++;
@@ -1915,7 +1916,7 @@ LRESULT CALLBACK MemViewCallB(HWND hwnd, UINT message, WPARAM wParam, LPARAM lPa
 					i &= 0x3FFF;
 					if(i < 0x2000) bar[i] = VPage[(i)>>10][(i)];
 					else if(i < 0x3F00) bar[i] = vnapage[(i>>10)&0x3][i&0x3FF];
-					else bar[i] = PALRAM[i&0x1F];
+					else bar[i] = READPAL_MOTHEROFALL(i & 0x1F);
 				}
 				dumpToFile(bar, sizeof(bar));
 				return 0;
@@ -1952,7 +1953,7 @@ LRESULT CALLBACK MemViewCallB(HWND hwnd, UINT message, WPARAM wParam, LPARAM lPa
 						if((addr >= 0x2000) && (addr < 0x3F00))
 							vnapage[(addr>>10)&0x3][addr&0x3FF] = v; //todo: this causes 0x3000-0x3f00 to mirror 0x2000-0x2f00, is this correct?
 						if((addr >= 0x3F00) && (addr < 0x3FFF))
-							PALRAM[addr&0x1F] = v;
+							PalettePoke(addr,v);
 					}
 				}
 				return 0;
@@ -2394,3 +2395,25 @@ void OpenFindDialog()
 		hMemFind = CreateDialog(fceu_hInstance,"MEMVIEWFIND",hMemView,MemFindCallB);
 	return;
 }
+
+void PalettePoke(uint32 addr, uint8 data)
+{
+	data = data & 0x3F;
+	addr = addr & 0x1F;
+	if ((addr & 3) == 0)
+	{
+		addr = (addr & 0xC) >> 2;
+		if (addr == 0)
+		{
+			PALRAM[0x00] = PALRAM[0x04] = PALRAM[0x08] = PALRAM[0x0C] = data;
+		}
+		else
+		{
+			UPALRAM[addr-1] = UPALRAM[0x10|(addr-1)] = data;
+		}
+	}
+	else
+	{
+		PALRAM[addr] = data;
+	}
+}

src/drivers/win/ppuview.cpp

@@ -29,13 +29,15 @@ HWND hPPUView;
 
 extern uint8 *VPage[8];
 extern uint8 PALRAM[0x20];
+extern uint8 UPALRAM[3];
 
 int PPUViewPosX, PPUViewPosY;
 bool PPUView_maskUnusedGraphics = true;
 bool PPUView_invertTheMask = false;
 int PPUView_sprite16Mode = 0;
 
-static uint8 palcache[36] = { 0xFF }; //palette cache
+static uint8 pallast[32+3] = { 0 }; // palette cache for change comparison
+static uint8 palcache[36] = { 0 }; //palette cache for drawing
 uint8 chrcache0[0x1000], chrcache1[0x1000], logcache0[0x1000], logcache1[0x1000]; //cache CHR, fixes a refresh problem when right-clicking
 uint8 *pattern0, *pattern1; //pattern table bitmap arrays
 uint8 *ppuv_palette;
@@ -177,18 +179,17 @@ void FCEUD_UpdatePPUView(int scanline, int refreshchr)
 	}
 
 	// update palette only if required
-	if (memcmp(palcache, PALRAM, 32) != 0)
+	if ((memcmp(pallast, PALRAM, 32) != 0) || (memcmp(pallast+32, UPALRAM, 3) != 0))
 	{
-		// bbit note: let para know that this if is useless and
+		memcpy(pallast, PALRAM, 32);
-		// will not work because of the lines below that change
+		memcpy(pallast+32, UPALRAM, 3);
-		// palcache which will make it not equal next time
 
 		// cache palette content
 		memcpy(palcache,PALRAM,32);
 		palcache[0x10] = palcache[0x00];
-		palcache[0x14] = palcache[0x00];
+		palcache[0x04] = palcache[0x14] = UPALRAM[0];
-		palcache[0x18] = palcache[0x00];
+		palcache[0x08] = palcache[0x18] = UPALRAM[1];
-		palcache[0x1C] = palcache[0x00];
+		palcache[0x0C] = palcache[0x1C] = UPALRAM[2];
 
 		//draw palettes
 		for (y = 0; y < PALETTEHEIGHT; y++)
@@ -220,7 +221,6 @@ void FCEUD_UpdatePPUView(int scanline, int refreshchr)
 			}
 			pbitmap += ((32*4*3)-6);
 		}
-		memcpy(palcache,PALRAM,32);        //palcache which will make it not equal next time
 	}
 
 	DrawPatternTable(pattern0,chrcache0,logcache0,pindex0);
@@ -428,7 +428,8 @@ INT_PTR CALLBACK PPUViewCallB(HWND hwndDlg, UINT uMsg, WPARAM wParam, LPARAM lPa
 			PPUViewSkip=100;
 
 			//clear cache
-			memset(palcache,0,32);
+			memset(pallast,0,32+3);
+			memset(palcache,0,36);
 			memset(chrcache0,0,0x1000);
 			memset(chrcache1,0,0x1000);
 			memset(logcache0,0,0x1000);
@@ -537,7 +538,6 @@ INT_PTR CALLBACK PPUViewCallB(HWND hwndDlg, UINT uMsg, WPARAM wParam, LPARAM lPa
 					mouse_x = (mouse_x - paletteDestX) / 32;
 					mouse_y = (mouse_y - paletteDestY) / 32;
 					int ix = (mouse_y<<4)|mouse_x;
-					if ((ix & 0x10) && !(ix & 0x03)) ix = 0; // palcache 0x10/14/18/1C is bogus $00 values
 					sprintf(str,"Palette: $%02X",palcache[ix]);
 					SetDlgItemText(hwndDlg,LBL_PPUVIEW_TILE1,"Tile:");
 					SetDlgItemText(hwndDlg,LBL_PPUVIEW_TILE2,"Tile:");

src/ppu.cpp

@@ -2198,7 +2198,7 @@ int FCEUX_PPU_Loop(int skip) {
 							{
 								pixel = addr & 0x1F;
 							}
-							pixelcolor = PALRAM[pixel];
+							pixelcolor = READPAL_MOTHEROFALL(pixel);
 						}
 
 						//generate the BG data