software rasterizer stub complete with terrible flat shaded tri renderer

This commit is contained in:
zeromus 2009-02-02 22:09:09 +00:00
parent 3d78ca9c1c
commit 257a138d82
4 changed files with 341 additions and 1 deletions

299
desmume/src/rasterize.cpp Normal file
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/* Copyright (C) 2006 yopyop
yopyop156@ifrance.com
yopyop156.ifrance.com
Copyright 2009 DeSmuME team
This file is part of DeSmuME
DeSmuME is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.
DeSmuME is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with DeSmuME; if not, write to the Free Software
Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include "Rasterize.h"
#include "common.h"
#include "render3D.h"
#include "gfx3d.h"
#include <algorithm>
using std::min;
using std::max;
template<typename T> T min(T a, T b, T c) { return min(min(a,b),c); }
template<typename T> T max(T a, T b, T c) { return max(max(a,b),c); }
static u16 screen[256*192];
void set_pixel(int x, int y, u16 color)
{
if(x<0 || y<0 || x>=256 || y>=192) return;
screen[y*256+x] = color | 0x8000;
}
void hline(int x, int y, int xe, u16 color)
{
for(int i=x;i<=xe;i++)
set_pixel(x,y,color);
}
//http://www.devmaster.net/forums/showthread.php?t=1884
int iround(float f) {
return (int)f; //lol
}
void triangle_from_devmaster(int x1, int y1, int x2, int y2, int x3, int y3, u16 color)
{
int desty = 0;
struct Vertex {
int x,y;
} v1, v2, v3;
v1.x = x1;
v1.y = y1;
v2.x = x2;
v2.y = y2;
v3.x = x3;
v3.y = y3;
// 28.4 fixed-point coordinates
const int Y1 = iround(16.0f * v1.y);
const int Y2 = iround(16.0f * v2.y);
const int Y3 = iround(16.0f * v3.y);
const int X1 = iround(16.0f * v1.x);
const int X2 = iround(16.0f * v2.x);
const int X3 = iround(16.0f * v3.x);
// Deltas
const int DX12 = X1 - X2;
const int DX23 = X2 - X3;
const int DX31 = X3 - X1;
const int DY12 = Y1 - Y2;
const int DY23 = Y2 - Y3;
const int DY31 = Y3 - Y1;
// Fixed-point deltas
const int FDX12 = DX12 << 4;
const int FDX23 = DX23 << 4;
const int FDX31 = DX31 << 4;
const int FDY12 = DY12 << 4;
const int FDY23 = DY23 << 4;
const int FDY31 = DY31 << 4;
// Bounding rectangle
int minx = (min(X1, X2, X3) + 0xF) >> 4;
int maxx = (max(X1, X2, X3) + 0xF) >> 4;
int miny = (min(Y1, Y2, Y3) + 0xF) >> 4;
int maxy = (max(Y1, Y2, Y3) + 0xF) >> 4;
// Block size, standard 8x8 (must be power of two)
const int q = 8;
// Start in corner of 8x8 block
minx &= ~(q - 1);
miny &= ~(q - 1);
//(char*&)colorBuffer += miny * stride;
desty = miny;
// Half-edge constants
int C1 = DY12 * X1 - DX12 * Y1;
int C2 = DY23 * X2 - DX23 * Y2;
int C3 = DY31 * X3 - DX31 * Y3;
// Correct for fill convention
if(DY12 < 0 || (DY12 == 0 && DX12 > 0)) C1++;
if(DY23 < 0 || (DY23 == 0 && DX23 > 0)) C2++;
if(DY31 < 0 || (DY31 == 0 && DX31 > 0)) C3++;
// Loop through blocks
for(int y = miny; y < maxy; y += q)
{
for(int x = minx; x < maxx; x += q)
{
// Corners of block
int x0 = x << 4;
int x1 = (x + q - 1) << 4;
int y0 = y << 4;
int y1 = (y + q - 1) << 4;
// Evaluate half-space functions
bool a00 = C1 + DX12 * y0 - DY12 * x0 > 0;
bool a10 = C1 + DX12 * y0 - DY12 * x1 > 0;
bool a01 = C1 + DX12 * y1 - DY12 * x0 > 0;
bool a11 = C1 + DX12 * y1 - DY12 * x1 > 0;
int a = (a00 << 0) | (a10 << 1) | (a01 << 2) | (a11 << 3);
bool b00 = C2 + DX23 * y0 - DY23 * x0 > 0;
bool b10 = C2 + DX23 * y0 - DY23 * x1 > 0;
bool b01 = C2 + DX23 * y1 - DY23 * x0 > 0;
bool b11 = C2 + DX23 * y1 - DY23 * x1 > 0;
int b = (b00 << 0) | (b10 << 1) | (b01 << 2) | (b11 << 3);
bool c00 = C3 + DX31 * y0 - DY31 * x0 > 0;
bool c10 = C3 + DX31 * y0 - DY31 * x1 > 0;
bool c01 = C3 + DX31 * y1 - DY31 * x0 > 0;
bool c11 = C3 + DX31 * y1 - DY31 * x1 > 0;
int c = (c00 << 0) | (c10 << 1) | (c01 << 2) | (c11 << 3);
// Skip block when outside an edge
if(a == 0x0 || b == 0x0 || c == 0x0) continue;
//unsigned int *buffer = colorBuffer;
int _desty = desty;
// Accept whole block when totally covered
if(a == 0xF && b == 0xF && c == 0xF)
{
for(int iy = 0; iy < q; iy++)
{
for(int ix = x; ix < x + q; ix++)
{
//buffer[ix] = 0x00007F00;<< // Green
set_pixel(ix,_desty,color);
}
//(char*&)buffer += stride;
_desty++;
}
}
else // Partially covered block
{
int CY1 = C1 + DX12 * y0 - DY12 * x0;
int CY2 = C2 + DX23 * y0 - DY23 * x0;
int CY3 = C3 + DX31 * y0 - DY31 * x0;
for(int iy = y; iy < y + q; iy++)
{
int CX1 = CY1;
int CX2 = CY2;
int CX3 = CY3;
for(int ix = x; ix < x + q; ix++)
{
if(CX1 > 0 && CX2 > 0 && CX3 > 0)
{
//buffer[ix] = 0x0000007F;<< // Blue
set_pixel(ix,_desty,color);
}
CX1 -= FDY12;
CX2 -= FDY23;
CX3 -= FDY31;
}
CY1 += FDX12;
CY2 += FDX23;
CY3 += FDX31;
//(char*&)buffer += stride;
_desty ++;
}
}
}
//(char*&)colorBuffer += q * stride;
desty += q;
}
}
static char Init(void)
{
return 1;
}
static void Reset() {}
static void Close() {}
static void VramReconfigureSignal() {}
static void GetLine(int line, u16* dst, u8* dstAlpha)
{
memcpy(dst,screen+(191-line)*256,512);
memset(dstAlpha,16,256);
}
static void GetLineCaptured(int line, u16* dst) {}
static void Render()
{
//transform verts and polys
//which order?
//A. clip
//B. backface cull
//C. transforms
memset(screen,0,256*192*2);
for(int i=0;i<gfx3d.vertlist->count;i++)
{
VERT &vert = gfx3d.vertlist->list[i];
//perspective division
vert.coord[0] = (vert.coord[0] + vert.coord[3]) / 2 / vert.coord[3];
vert.coord[1] = (vert.coord[1] + vert.coord[3]) / 2 / vert.coord[3];
vert.coord[2] = (vert.coord[2] + vert.coord[3]) / 2 / vert.coord[3];
vert.coord[3] = 1;
//transform to viewport. this is badly broken
vert.coord[0] = (vert.coord[0])*128;
vert.coord[1] = (vert.coord[1])*96;
int zzz=9;
}
//iterate over gfx3d.polylist and gfx3d.vertlist
for(int i=0;i<gfx3d.polylist->count;i++) {
POLY *poly = &gfx3d.polylist->list[gfx3d.indexlist[i]];
int type = poly->type;
if(type == 3) {
VERT* vert[3] = {
&gfx3d.vertlist->list[poly->vertIndexes[0]],
&gfx3d.vertlist->list[poly->vertIndexes[1]],
&gfx3d.vertlist->list[poly->vertIndexes[2]],
};
u16 color = vert[0]->color[0] | (vert[0]->color[1]<<5) | (vert[0]->color[2]<<10);
triangle_from_devmaster(
vert[0]->coord[0],vert[0]->coord[1],
vert[1]->coord[0],vert[1]->coord[1],
vert[2]->coord[0],vert[2]->coord[1],
color);
}
}
}
GPU3DInterface gpu3DRasterize = {
"SoftRasterizer",
Init,
Reset,
Close,
Render,
VramReconfigureSignal,
GetLine,
GetLineCaptured
};

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desmume/src/rasterize.h Normal file
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/* Copyright (C) 2006 yopyop
yopyop156@ifrance.com
yopyop156.ifrance.com
Copyright 2009 DeSmuME team
This file is part of DeSmuME
DeSmuME is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.
DeSmuME is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with DeSmuME; if not, write to the Free Software
Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
#ifndef _RASTERIZE_H_
#define _RASTERIZE_H_
#include "render3D.h"
extern GPU3DInterface gpu3DRasterize;
#endif

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@ -1,7 +1,7 @@
<?xml version="1.0" encoding="shift_jis"?>
<VisualStudioProject
ProjectType="Visual C++"
Version="8,00"
Version="8.00"
Name="DeSmuME_VS2005"
ProjectGUID="{9F5F72A1-D3A5-4918-B460-E076B16D10A9}"
RootNamespace="DeSmuME"
@ -1056,6 +1056,14 @@
RelativePath="..\OGLRender.h"
>
</File>
<File
RelativePath="..\rasterize.cpp"
>
</File>
<File
RelativePath="..\rasterize.h"
>
</File>
<File
RelativePath="..\readwrite.cpp"
>

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#include "FirmConfig.h"
#include "AboutBox.h"
#include "OGLRender.h"
#include "rasterize.h"
#include "../gfx3d.h"
#include "../render3D.h"
#include "../gdbstub.h"
@ -185,6 +186,7 @@ NULL
GPU3DInterface *core3DList[] = {
&gpu3DNull,
&gpu3Dgl,
&gpu3DRasterize,
NULL
};