move viewport transform to polygon setup

3 files changed, 84 insertions, 89 deletions

diff --git a/GPU3D.cpp b/GPU3D.cpp
index b10f1b1..ed1ab52 100644
--- a/GPU3D.cpp
+++ b/GPU3D.cpp
@@ -217,7 +217,7 @@ u32 CurRAMBank;
 u32 ClearAttr1, ClearAttr2;
 
 u32 FlushRequest;
-u32 FlushAttributes, CurFlushAttributes;
+u32 FlushAttributes;
 
 
 
@@ -293,7 +293,6 @@ void Reset()
 
     FlushRequest = 0;
     FlushAttributes = 0;
-    CurFlushAttributes = 0;
 
     SoftRenderer::Reset();
 }
@@ -456,7 +455,6 @@ void ClipSegment(Vertex* outbuf, Vertex* vout, Vertex* vin)
     INTERPOLATE(TexCoords[1]);
 
     mid.Clipped = true;
-    mid.ViewportTransformDone = false;
 
 #undef INTERPOLATE
     *outbuf = mid;
@@ -765,6 +763,7 @@ void SubmitPolygon()
     if (NumPolygons >= 2048 || NumVertices+c > 6144)
     {
         LastStripPolygon = NULL;
+        // TODO: set DISP3DCNT overflow flag
         return;
     }
 
@@ -805,13 +804,79 @@ void SubmitPolygon()
 
     for (int i = clipstart; i < c; i++)
     {
-        CurVertexRAM[NumVertices] = clippedvertices[1][i];
-        poly->Vertices[i] = &CurVertexRAM[NumVertices];
+        Vertex* vtx = &CurVertexRAM[NumVertices];
+        *vtx = clippedvertices[1][i];
+        poly->Vertices[i] = vtx;
 
         NumVertices++;
         poly->NumVertices++;
+
+        // viewport transform
+        s32 posX, posY, posZ;
+        s32 w = vtx->Position[3];
+        if (w == 0)
+        {
+            posX = 0;
+            posY = 0;
+            posZ = 0;
+            w = 0x1000;
+        }
+        else
+        {
+            posX = (((s64)(vtx->Position[0] + w) * Viewport[2]) / (((s64)w) << 1)) + Viewport[0];
+            posY = (((s64)(-vtx->Position[1] + w) * Viewport[3]) / (((s64)w) << 1)) + Viewport[1];
+
+            if (FlushAttributes & 0x2) posZ = w;
+            else                       posZ = (((s64)vtx->Position[2] * 0x800000) / w) + 0x7FFEFF;
+        }
+
+        if      (posX < 0)        posX = 0;
+        else if (posX > 256)      posX = 256;
+        if      (posY < 0)        posY = 0;
+        else if (posY > 192)      posY = 192;
+        if      (posZ < 0)        posZ = 0;
+        else if (posZ > 0xFFFFFF) posZ = 0xFFFFFF;
+
+        vtx->FinalPosition[0] = posX;
+        vtx->FinalPosition[1] = posY;
+        vtx->FinalPosition[2] = posZ;
+        vtx->FinalPosition[3] = w;
+
+        vtx->FinalColor[0] = vtx->Color[0] >> 12;
+        if (vtx->FinalColor[0]) vtx->FinalColor[0] = ((vtx->FinalColor[0] << 4) + 0xF);
+        vtx->FinalColor[1] = vtx->Color[1] >> 12;
+        if (vtx->FinalColor[1]) vtx->FinalColor[1] = ((vtx->FinalColor[1] << 4) + 0xF);
+        vtx->FinalColor[2] = vtx->Color[2] >> 12;
+        if (vtx->FinalColor[2]) vtx->FinalColor[2] = ((vtx->FinalColor[2] << 4) + 0xF);
     }
 
+    // determine bounds of the polygon
+    u32 vtop = 0, vbot = 0;
+    s32 ytop = 192, ybot = 0;
+    s32 xtop = 256, xbot = 0;
+
+    for (int i = 0; i < c; i++)
+    {
+        Vertex* vtx = poly->Vertices[i];
+
+        if (vtx->FinalPosition[1] < ytop || (vtx->FinalPosition[1] == ytop && vtx->FinalPosition[0] < xtop))
+        {
+            xtop = vtx->FinalPosition[0];
+            ytop = vtx->FinalPosition[1];
+            vtop = i;
+        }
+        if (vtx->FinalPosition[1] > ybot || (vtx->FinalPosition[1] == ybot && vtx->FinalPosition[0] > xbot))
+        {
+            xbot = vtx->FinalPosition[0];
+            ybot = vtx->FinalPosition[1];
+            vbot = i;
+        }
+    }
+
+    poly->VTop = vtop; poly->VBottom = vbot;
+    poly->YTop = ytop; poly->YBottom = ybot;
+    poly->XTop = xtop; poly->XBottom = xbot;
+
     if (PolygonMode >= 2)
         LastStripPolygon = poly;
     else
@@ -845,7 +910,6 @@ void SubmitVertex()
     }
 
     vertextrans->Clipped = false;
-    vertextrans->ViewportTransformDone = false;
 
     VertexNum++;
     VertexNumInPoly++;
@@ -1562,9 +1626,7 @@ void VBlank()
 {
     if (FlushRequest)
     {
-        SoftRenderer::DispCnt = DispCnt;
-        SoftRenderer::AlphaRef = AlphaRef;
-        SoftRenderer::RenderFrame(CurFlushAttributes, CurVertexRAM, CurPolygonRAM, NumPolygons);
+        SoftRenderer::RenderFrame(CurVertexRAM, CurPolygonRAM, NumPolygons);
 
         CurRAMBank = CurRAMBank?0:1;
         CurVertexRAM = &VertexRAM[CurRAMBank ? 6144 : 0];
@@ -1574,7 +1636,6 @@ void VBlank()
         NumPolygons = 0;
 
         FlushRequest = 0;
-        CurFlushAttributes = FlushAttributes;
     }
 }
 
diff --git a/GPU3D.h b/GPU3D.h
index e2948bf..c1adc2f 100644
--- a/GPU3D.h
+++ b/GPU3D.h
@@ -36,8 +36,6 @@ typedef struct
     s32 FinalPosition[4];
     s32 FinalColor[3];
 
-    bool ViewportTransformDone;
-
 } Vertex;
 
 typedef struct
@@ -52,9 +50,14 @@ typedef struct
     bool FacingView;
     bool Translucent;
 
+    u32 VTop, VBottom; // vertex indices
+    s32 YTop, YBottom; // Y coords
+    s32 XTop, XBottom; // associated X coords
+
 } Polygon;
 
 extern u32 DispCnt;
+extern u32 AlphaRef;
 extern s32 Viewport[4];
 extern u32 ClearAttr1, ClearAttr2;
 
@@ -81,14 +84,11 @@ void Write32(u32 addr, u32 val);
 namespace SoftRenderer
 {
 
-extern u32 DispCnt;
-extern u32 AlphaRef;
-
 bool Init();
 void DeInit();
 void Reset();
 
-void RenderFrame(u32 attr, Vertex* vertices, Polygon* polygons, int npolys);
+void RenderFrame(Vertex* vertices, Polygon* polygons, int npolys);
 u32* GetLine(int line);
 
 }
diff --git a/GPU3D_Soft.cpp b/GPU3D_Soft.cpp
index 1566ee8..5c9dc8e 100644
--- a/GPU3D_Soft.cpp
+++ b/GPU3D_Soft.cpp
@@ -27,9 +27,6 @@ namespace GPU3D
 namespace SoftRenderer
 {
 
-u32 DispCnt;
-u32 AlphaRef;
-
 u32 ColorBuffer[256*192];
 u32 DepthBuffer[256*192];
 u32 AttrBuffer[256*192];
@@ -336,77 +333,14 @@ u32 RenderPixel(Polygon* polygon, s32 x, s32 y, s32 z, u8 vr, u8 vg, u8 vb, s16
     return r | (g << 8) | (b << 16) | (a << 24);
 }
 
-void RenderPolygon(Polygon* polygon, u32 wbuffer)
+void RenderPolygon(Polygon* polygon)
 {
     int nverts = polygon->NumVertices;
     bool isline = false;
 
-    int vtop = 0, vbot = 0;
-    s32 ytop = 192, ybot = 0;
-    s32 xtop = 256, xbot = 0;
-
-    // process the vertices, transform to screen coordinates
-    // find the topmost and bottommost vertices of the polygon
-
-    for (int i = 0; i < nverts; i++)
-    {
-        Vertex* vtx = polygon->Vertices[i];
-
-        if (!vtx->ViewportTransformDone)
-        {
-            s32 posX, posY, posZ;
-            s32 w = vtx->Position[3];
-            if (w == 0)
-            {
-                posX = 0;
-                posY = 0;
-                posZ = 0;
-                w = 0x1000;
-            }
-            else
-            {
-                posX = (((s64)(vtx->Position[0] + w) * Viewport[2]) / (((s64)w) << 1)) + Viewport[0];
-                posY = (((s64)(-vtx->Position[1] + w) * Viewport[3]) / (((s64)w) << 1)) + Viewport[1];
-
-                if (wbuffer) posZ = w;
-                else         posZ = (((s64)vtx->Position[2] * 0x800000) / w) + 0x7FFEFF;
-            }
-
-            if      (posX < 0)   posX = 0;
-            else if (posX > 256) posX = 256;
-            if      (posY < 0)   posY = 0;
-            else if (posY > 192) posY = 192;
-            if      (posZ < 0)        posZ = 0;
-            else if (posZ > 0xFFFFFF) posZ = 0xFFFFFF;
-
-            vtx->FinalPosition[0] = posX;
-            vtx->FinalPosition[1] = posY;
-            vtx->FinalPosition[2] = posZ;
-            vtx->FinalPosition[3] = w;
-
-            vtx->FinalColor[0] = vtx->Color[0] >> 12;
-            if (vtx->FinalColor[0]) vtx->FinalColor[0] = ((vtx->FinalColor[0] << 4) + 0xF);
-            vtx->FinalColor[1] = vtx->Color[1] >> 12;
-            if (vtx->FinalColor[1]) vtx->FinalColor[1] = ((vtx->FinalColor[1] << 4) + 0xF);
-            vtx->FinalColor[2] = vtx->Color[2] >> 12;
-            if (vtx->FinalColor[2]) vtx->FinalColor[2] = ((vtx->FinalColor[2] << 4) + 0xF);
-
-            vtx->ViewportTransformDone = true;
-        }
-
-        if (vtx->FinalPosition[1] < ytop || (vtx->FinalPosition[1] == ytop && vtx->FinalPosition[0] < xtop))
-        {
-            xtop = vtx->FinalPosition[0];
-            ytop = vtx->FinalPosition[1];
-            vtop = i;
-        }
-        if (vtx->FinalPosition[1] > ybot || (vtx->FinalPosition[1] == ybot && vtx->FinalPosition[0] > xbot))
-        {
-            xbot = vtx->FinalPosition[0];
-            ybot = vtx->FinalPosition[1];
-            vbot = i;
-        }
-    }
+    int vtop = polygon->VTop, vbot = polygon->VBottom;
+    s32 ytop = polygon->YTop, ybot = polygon->YBottom;
+    s32 xtop = polygon->XTop, xbot = polygon->XBottom;
 
     if (ytop > 191) return;
 
@@ -837,7 +771,7 @@ void RenderPolygon(Polygon* polygon, u32 wbuffer)
     }
 }
 
-void RenderFrame(u32 attr, Vertex* vertices, Polygon* polygons, int npolys)
+void RenderFrame(Vertex* vertices, Polygon* polygons, int npolys)
 {
     u32 polyid = (ClearAttr1 >> 24) & 0x3F;
 
@@ -900,13 +834,13 @@ void RenderFrame(u32 attr, Vertex* vertices, Polygon* polygons, int npolys)
     for (int i = 0; i < npolys; i++)
     {
         if (polygons[i].Translucent) continue;
-        RenderPolygon(&polygons[i], attr&0x2);
+        RenderPolygon(&polygons[i]);
     }
 
     for (int i = 0; i < npolys; i++)
     {
         if (!polygons[i].Translucent) continue;
-        RenderPolygon(&polygons[i], attr&0x2);
+        RenderPolygon(&polygons[i]);
     }
 }