some debuts of 3D drawing.

it can draw non-strip polygons, filled with a fixed color. oh and it doesn't work if they're facing back.

6 files changed, 183 insertions, 9 deletions

diff --git a/GPU2D.cpp b/GPU2D.cpp
index 906be66..5168402 100644
--- a/GPU2D.cpp
+++ b/GPU2D.cpp
@@ -290,7 +290,7 @@ void GPU2D::DrawScanlineBGMode(u32 line, u32* spritebuf, u16* dst)
             if (DispCnt & 0x0100)
             {
                 if ((!Num) && (DispCnt & 0x8))
-                    {} // TODO
+                    DrawBG_3D(line, dst);
                 else
                     DrawBG_Text(line, dst, 0);
             }
@@ -333,6 +333,25 @@ void GPU2D::DrawScanline_Mode1(u32 line, u16* dst)
 }
 
 
+void GPU2D::DrawBG_3D(u32 line, u16* dst)
+{
+    // TODO: scroll, etc
+
+    u8* src = GPU3D::GetLine(line);
+    for (int i = 0; i < 256; i++)
+    {
+        // TODO: color buffer should be 18bit!!
+
+        u8 r = *src++;
+        u8 g = *src++;
+        u8 b = *src++;
+        u8 a = *src++;
+        if (a == 0) continue;
+
+        dst[i] = (r >> 1) | ((g >> 1) << 5) | ((b >> 1) << 10);
+    }
+}
+
 void GPU2D::DrawBG_Text(u32 line, u16* dst, u32 bgnum)
 {
     u16 bgcnt = BGCnt[bgnum];
diff --git a/GPU2D.h b/GPU2D.h
index 3f767ea..ced8879 100644
--- a/GPU2D.h
+++ b/GPU2D.h
@@ -59,6 +59,7 @@ private:
     template<u32 bgmode> void DrawScanlineBGMode(u32 line, u32* spritebuf, u16* dst);
     void DrawScanline_Mode1(u32 line, u16* dst);
 
+    void DrawBG_3D(u32 line, u16* dst);
     void DrawBG_Text(u32 line, u16* dst, u32 num);
     void DrawBG_Extended(u32 line, u16* dst, u32 bgnum);
 
diff --git a/GPU3D.cpp b/GPU3D.cpp
index 1ee350e..a40e685 100644
--- a/GPU3D.cpp
+++ b/GPU3D.cpp
@@ -1169,6 +1169,11 @@ void VBlank()
     NumPolygons = 0;
 }
 
+u8* GetLine(int line)
+{
+    return SoftRenderer::GetLine(line);
+}
+
 
 u8 Read8(u32 addr)
 {
diff --git a/GPU3D.h b/GPU3D.h
index d65fa9a..d9e7e1a 100644
--- a/GPU3D.h
+++ b/GPU3D.h
@@ -36,6 +36,8 @@ typedef struct
 
 } Polygon;
 
+extern s32 Viewport[4];
+
 bool Init();
 void DeInit();
 void Reset();
@@ -45,6 +47,7 @@ void CheckFIFOIRQ();
 void CheckFIFODMA();
 
 void VBlank();
+u8* GetLine(int line);
 
 u8 Read8(u32 addr);
 u16 Read16(u32 addr);
@@ -61,6 +64,7 @@ void DeInit();
 void Reset();
 
 void RenderFrame(Vertex* vertices, Polygon* polygons, int npolys);
+u8* GetLine(int line);
 
 }
 
diff --git a/GPU3D_Soft.cpp b/GPU3D_Soft.cpp
index 38d3539..9c057e9 100644
--- a/GPU3D_Soft.cpp
+++ b/GPU3D_Soft.cpp
@@ -32,7 +32,7 @@ u8 ColorBuffer[256*192 * 4];
 
 bool Init()
 {
-    //
+    return true;
 }
 
 void DeInit()
@@ -46,9 +46,148 @@ void Reset()
 }
 
 
+void RenderPolygon(Polygon* polygon)
+{
+    int nverts = polygon->NumVertices;
+
+    int vtop, vbot;
+    s32 ytop = 191, ybot = 0;
+    s32 scrcoords[10][3];
+
+    // find the topmost and bottommost vertices of the polygon
+
+    for (int i = 0; i < nverts; i++)
+    {
+        Vertex* vtx = polygon->Vertices[i];
+
+        s32 scrX = (((vtx->Position[0] + 0x1000) * Viewport[2]) >> 13) + Viewport[0];
+        s32 scrY = (((vtx->Position[1] + 0x1000) * Viewport[3]) >> 13) + Viewport[1];
+        if (scrX > 255) scrX = 255;
+        if (scrY > 191) scrY = 191;
+
+        scrcoords[i][0] = scrX;
+        scrcoords[i][1] = 191 - scrY;
+        scrcoords[i][2] = 0; // TODO: Z
+
+        if (scrcoords[i][1] < ytop)
+        {
+            ytop = scrcoords[i][1];
+            vtop = i;
+        }
+        if (scrcoords[i][1] > ybot)
+        {
+            ybot = scrcoords[i][1];
+            vbot = i;
+        }
+    }
+
+    // draw, line per line
+
+    int lcur = vtop, rcur = vtop;
+    int lnext, rnext;
+    s32 lstep, rstep;
+    //s32 xmin, xmax;
+
+    lnext = lcur + 1;
+    if (lnext >= nverts) lnext = 0;
+    rnext = rcur - 1;
+    if (rnext < 0) rnext = nverts - 1;
+
+    /*if ((scrcoords[lnext][1] - scrcoords[lcur][1]) == 0) lstep = 0; else
+    lstep = ((scrcoords[lnext][0] - scrcoords[lcur][0]) << 12) / (scrcoords[lnext][1] - scrcoords[lcur][1]);
+    if ((scrcoords[rnext][1] - scrcoords[rcur][1]) == 0) rstep = 0; else
+    rstep = ((scrcoords[rnext][0] - scrcoords[rcur][0]) << 12) / (scrcoords[rnext][1] - scrcoords[rcur][1]);*/
+
+    //xmin = scrcoords[lcur][0] << 12;
+    //xmax = scrcoords[rcur][0] << 12;
+
+    for (s32 y = ytop; y <= ybot; y++)
+    {
+        if (y == scrcoords[lnext][1] && y < ybot)
+        {
+            lcur++;
+            if (lcur >= nverts) lcur = 0;
+
+            lnext = lcur + 1;
+            if (lnext >= nverts) lnext = 0;
+
+            //lstep = ((scrcoords[lnext][0] - scrcoords[lcur][0]) << 12) / (scrcoords[lnext][1] - scrcoords[lcur][1]);
+            //xmin = scrcoords[lcur][0] << 12;
+        }
+
+        if (y == scrcoords[rnext][1] && y < ybot)
+        {
+            rcur--;
+            if (rcur < 0) rcur = nverts - 1;
+
+            rnext = rcur - 1;
+            if (rnext < 0) rnext = nverts - 1;
+
+            //rstep = ((scrcoords[rnext][0] - scrcoords[rcur][0]) << 12) / (scrcoords[rnext][1] - scrcoords[rcur][1]);
+            //xmax = scrcoords[rcur][0] << 12;
+        }
+
+        s32 lfactor, rfactor;
+
+        if (scrcoords[lnext][1] == scrcoords[lcur][1])
+            lfactor = 0;
+        else
+            lfactor = ((y - scrcoords[lcur][1]) << 12) / (scrcoords[lnext][1] - scrcoords[lcur][1]);
+
+        if (scrcoords[rnext][1] == scrcoords[rcur][1])
+            rfactor = 0;
+        else
+            rfactor = ((y - scrcoords[rcur][1]) << 12) / (scrcoords[rnext][1] - scrcoords[rcur][1]);
+
+        s32 xmin = scrcoords[lcur][0] + (((scrcoords[lnext][0] - scrcoords[lcur][0]) * lfactor) >> 12);
+        s32 xmax = scrcoords[rcur][0] + (((scrcoords[rnext][0] - scrcoords[rcur][0]) * rfactor) >> 12);
+
+        for (s32 x = xmin; x <= xmax; x++)
+        {
+            u8* pixel = &ColorBuffer[((256*y) + x) * 4];
+            pixel[0] = 0;
+            pixel[1] = 63;
+            pixel[2] = 0;
+            pixel[3] = 31;
+        }
+    }
+
+    // test
+    /*for (int i = 0; i < nverts; i++)
+    {
+        Vertex* vtx = polygon->Vertices[i];
+
+        s32 scrX = (((vtx->Position[0] + 0x1000) * Viewport[2]) >> 13) + Viewport[0];
+        s32 scrY = (((vtx->Position[1] + 0x1000) * Viewport[3]) >> 13) + Viewport[1];
+        if (scrX > 255) scrX = 255;
+        if (scrY > 191) scrY = 191;
+
+        u8* pixel = &ColorBuffer[((256*scrY) + scrX) * 4];
+        pixel[0] = 0;
+        pixel[1] = 63;
+        pixel[2] = 0;
+        pixel[3] = 31;
+    }*/
+}
+
 void RenderFrame(Vertex* vertices, Polygon* polygons, int npolys)
 {
-    //
+    // TODO: render translucent polygons last
+
+    for (int i = 0; i < 256*192; i++)
+    {
+        ((u32*)ColorBuffer)[i] = 0x1F000000;
+    }
+
+    for (int i = 0; i < npolys; i++)
+    {
+        RenderPolygon(&polygons[i]);
+    }
+}
+
+u8* GetLine(int line)
+{
+    return &ColorBuffer[line * 256 * 4];
 }
 
 }
diff --git a/melonDS.depend b/melonDS.depend
index c13ca03..7c0308e 100644
--- a/melonDS.depend
+++ b/melonDS.depend
@@ -10,7 +10,7 @@
 
 1481161027 c:\documents\sources\melonds\types.h
 
-1486730943 source:c:\documents\sources\melonds\nds.cpp
+1486778178 source:c:\documents\sources\melonds\nds.cpp
 	<stdio.h>
 	<string.h>
 	"NDS.h"
@@ -24,7 +24,7 @@
 	"RTC.h"
 	"Wifi.h"
 
-1486512922 source:c:\documents\sources\melonds\arm.cpp
+1486736660 source:c:\documents\sources\melonds\arm.cpp
 	<stdio.h>
 	"NDS.h"
 	"ARM.h"
@@ -87,13 +87,13 @@
 	"NDS.h"
 	"SPI.h"
 
-1486736522 source:c:\documents\sources\melonds\gpu2d.cpp
+1486778220 source:c:\documents\sources\melonds\gpu2d.cpp
 	<stdio.h>
 	<string.h>
 	"NDS.h"
 	"GPU.h"
 
-1486736507 c:\documents\sources\melonds\gpu2d.h
+1486777351 c:\documents\sources\melonds\gpu2d.h
 
 1481040524 c:\documents\sources\melonds\wifi.h
 
@@ -146,12 +146,18 @@
 	"NDS.h"
 	"NDSCart.h"
 
-1486736374 c:\documents\sources\melonds\gpu3d.h
+1486777933 c:\documents\sources\melonds\gpu3d.h
 
-1486736648 source:c:\documents\sources\melonds\gpu3d.cpp
+1486777278 source:c:\documents\sources\melonds\gpu3d.cpp
 	<stdio.h>
 	<string.h>
 	"NDS.h"
 	"GPU.h"
 	"FIFO.h"
 
+1486781263 source:c:\documents\sources\melonds\gpu3d_soft.cpp
+	<stdio.h>
+	<string.h>
+	"NDS.h"
+	"GPU3D.h"
+