fixes to tiled extended BGs. support for 256color/direct bitmap BGs.

GPU2D.cpp

@@ -303,7 +303,6 @@ void GPU2D::DrawBG_Text(u32 line, u16* dst, u32 bgnum)
     u16 yoff = BGYPos[bgnum] + line;
 
     u32 widexmask = (bgcnt & 0x4000) ? 0x100 : 0;
-    //u32 ymask = (bgcnt & 0x8000) ? 0x1FF : 0xFF;
 
     extpal = (bgcnt & 0x0080) && (DispCnt & 0x40000000);
 
@@ -455,16 +454,89 @@ void GPU2D::DrawBG_Extended(u32 line, u16* dst, u32 bgnum)
     u32 extpal;
 
     u32 coordmask;
+    u32 yshift;
     switch (bgcnt & 0xC000)
     {
-    case 0x0000: coordmask = 0x07800; break;
+    case 0x0000: coordmask = 0x07800; yshift = 7; break;
-    case 0x4000: coordmask = 0x0F800; break;
+    case 0x4000: coordmask = 0x0F800; yshift = 8; break;
-    case 0x8000: coordmask = 0x1F800; break;
+    case 0x8000: coordmask = 0x1F800; yshift = 9; break;
-    case 0xC000: coordmask = 0x3F800; break;
+    case 0xC000: coordmask = 0x3F800; yshift = 10; break;
     }
 
+    u32 overflowmask;
+    if (bgcnt & 0x2000) overflowmask = 0;
+    else                overflowmask = ~(coordmask | 0x7FF);
+
     extpal = (DispCnt & 0x40000000);
 
+    s16 rotA = BGRotA[bgnum-2];
+    s16 rotB = BGRotB[bgnum-2];
+    s16 rotC = BGRotC[bgnum-2];
+    s16 rotD = BGRotD[bgnum-2];
+
+    s32 rotX = BGXCenter[bgnum-2];
+    s32 rotY = BGYCenter[bgnum-2];
+
+    // hax
+    rotX += line*rotB;
+    rotY += line*rotD;
+
+    if (bgcnt & 0x0080)
+    {
+        // bitmap modes
+
+        if (Num) tileset = (u8*)GPU::VRAM_BBG[((bgcnt & 0x003C) >> 2)];
+        else     tileset = (u8*)GPU::VRAM_ABG[((bgcnt & 0x003C) >> 2)];
+        if (!tileset) return;
+
+        coordmask |= 0x7FF;
+
+        if (bgcnt & 0x0004)
+        {
+            // direct color bitmap
+
+            u16* bitmap = (u16*)tileset;
+
+            for (int i = 0; i < 256; i++)
+            {
+                if (!((rotX|rotY) & overflowmask))
+                {
+                    u16 color = bitmap[(((rotY & coordmask) >> 8) << yshift) + ((rotX & coordmask) >> 8)];
+
+                    if (color & 0x8000)
+                        dst[i] = color;
+                }
+
+                rotX += rotA;
+                rotY += rotC;
+            }
+        }
+        else
+        {
+            // 256-color bitmap
+
+            if (Num) pal = (u16*)&GPU::Palette[0x400];
+            else     pal = (u16*)&GPU::Palette[0];
+
+            for (int i = 0; i < 256; i++)
+            {
+                if (!((rotX|rotY) & overflowmask))
+                {
+                    u8 color = tileset[(((rotY & coordmask) >> 8) << yshift) + ((rotX & coordmask) >> 8)];
+
+                    if (color)
+                        dst[i] = pal[color];
+                }
+
+                rotX += rotA;
+                rotY += rotC;
+            }
+        }
+    }
+    else
+    {
+        // shitty mode
+
         if (Num)
         {
             tileset = (u8*)GPU::VRAM_BBG[((bgcnt & 0x003C) >> 2)];
@@ -504,30 +576,13 @@ void GPU2D::DrawBG_Extended(u32 line, u16* dst, u32 bgnum)
         u16* curpal;
         u8* pixels;
 
-    s16 rotA = BGRotA[bgnum-2];
+        yshift -= 3;
-    s16 rotB = BGRotB[bgnum-2];
-    s16 rotC = BGRotC[bgnum-2];
-    s16 rotD = BGRotD[bgnum-2];
-
-    s32 rotX = BGXCenter[bgnum-2];
-    s32 rotY = BGYCenter[bgnum-2];
-
-    // hax
-    rotX += line*rotB;
-    rotY += line*rotD;
-
-    if (bgcnt & 0x0080)
-    {
-        // bitmap modes
-        // TODO
-    }
-    else
-    {
-        // shitty mode
 
         for (int i = 0; i < 256; i++)
         {
-            curtile = tilemap[((rotY & coordmask) >> 5) + ((rotX & coordmask) >> 11)];
+            if (!((rotX|rotY) & overflowmask))
+            {
+                curtile = tilemap[(((rotY & coordmask) >> 11) << yshift) + ((rotX & coordmask) >> 11)];
                 curpal = pal;
                 if (extpal) curpal += ((curtile & 0xF000) >> 4);
                 pixels = tileset + ((curtile & 0x03FF) << 6);
@@ -544,6 +599,7 @@ void GPU2D::DrawBG_Extended(u32 line, u16* dst, u32 bgnum)
 
                 if (color)
                     dst[i] = curpal[color];
+            }
 
             rotX += rotA;
             rotY += rotC;

NDS.cpp

@@ -274,7 +274,7 @@ void Reset()
     // test
     //LoadROM();
     //LoadFirmware();
-    NDSCart::LoadROM("rom/nsmb.nds");
+    NDSCart::LoadROM("rom/raving.nds");
 
     Running = true; // hax
 }

melonDS.depend

@@ -10,7 +10,7 @@
 
 1481161027 c:\documents\sources\melonds\types.h
 
-1486143063 source:c:\documents\sources\melonds\nds.cpp
+1486162025 source:c:\documents\sources\melonds\nds.cpp
 	<stdio.h>
 	<string.h>
 	"NDS.h"
@@ -86,7 +86,7 @@
 	"NDS.h"
 	"SPI.h"
 
-1486144037 source:c:\documents\sources\melonds\gpu2d.cpp
+1486162082 source:c:\documents\sources\melonds\gpu2d.cpp
 	<stdio.h>
 	<string.h>
 	"NDS.h"