perspective-correct Gouraud

This commit is contained in:
StapleButter 2017-02-15 17:49:14 +01:00
parent ef7fbf8b03
commit 676e5b32cc
2 changed files with 27 additions and 46 deletions

View File

@ -89,13 +89,14 @@ void RenderPolygon(Polygon* polygon)
{
Vertex* vtx = polygon->Vertices[i];
s32 posX, posY, posZ;
s32 posX, posY, posZ, posW;
s32 w = vtx->Position[3];
if (w == 0)
{
posX = 0;
posY = 0;
posZ = 0;
posW = 0x1000;
}
else
{
@ -103,17 +104,12 @@ void RenderPolygon(Polygon* polygon)
posX = ((s64)vtx->Position[0] << 12) / w;
posY = ((s64)vtx->Position[1] << 12) / w;
posZ = ((s64)vtx->Position[2] << 12) / w;
posW = w;
}
//s32 posX = vtx->Position[0];
//s32 posY = vtx->Position[1];
//printf("xy: %08X %08X %08X\n", vtx->Position[0], vtx->Position[1], vtx->Position[3]);
//printf("w_inv: %08X res: %08X %08X\n", w_inv, posX, posY);
s32 scrX = (((posX + 0x1000) * Viewport[2]) >> 13) + Viewport[0];
s32 scrY = (((posY + 0x1000) * Viewport[3]) >> 13) + Viewport[1];
s32 scrZ = (((s64)(posZ + 0x1000) * 0xFFFFFF) >> 13);
s32 scrW = (((s64)(w + 0x1000) * 0xFFFFFF) >> 13);
if (scrX > 255) scrX = 255;
if (scrY > 191) scrY = 191;
if (scrZ > 0xFFFFFF) scrZ = 0xFFFFFF;
@ -124,7 +120,7 @@ void RenderPolygon(Polygon* polygon)
scrcoords[i][0] = scrX;
scrcoords[i][1] = 191 - scrY;
scrcoords[i][2] = scrZ;
scrcoords[i][3] = scrW;
scrcoords[i][3] = posW;
if (scrcoords[i][1] < ytop)
{
@ -238,25 +234,24 @@ void RenderPolygon(Polygon* polygon)
if (xl<0 || xr>255) continue; // hax
//if (vlcur->Color[0]==0 && vlcur->Color[1]==63 && vlcur->Color[2]==0)
/*printf("y:%d xleft:%d xright:%d %d,%d %d,%d | left: %d to %d right: %d to %d\n",
y, xl, xr, lcur, rcur, vtop, vbot,
scrcoords[lcur][0], scrcoords[lnext][0],
scrcoords[rcur][0], scrcoords[rnext][0]);*/
s32 zl = scrcoords[lcur][2] + (((s64)(scrcoords[lnext][2] - scrcoords[lcur][2]) * lfactor) >> 12);
s32 zr = scrcoords[rcur][2] + (((s64)(scrcoords[rnext][2] - scrcoords[rcur][2]) * rfactor) >> 12);
//s32 wl = scrcoords[lcur][3] + (((s64)(scrcoords[lnext][3] - scrcoords[lcur][3]) * lfactor) >> 12);
//s32 wr = scrcoords[rcur][3] + (((s64)(scrcoords[rnext][3] - scrcoords[rcur][3]) * rfactor) >> 12);
s32 wl = scrcoords[lcur][3] + (((s64)(scrcoords[lnext][3] - scrcoords[lcur][3]) * lfactor) >> 12);
s32 wr = scrcoords[rcur][3] + (((s64)(scrcoords[rnext][3] - scrcoords[rcur][3]) * rfactor) >> 12);
u8 rl = vlcur->Color[0] + (((vlnext->Color[0] - vlcur->Color[0]) * lfactor) >> 12);
u8 gl = vlcur->Color[1] + (((vlnext->Color[1] - vlcur->Color[1]) * lfactor) >> 12);
u8 bl = vlcur->Color[2] + (((vlnext->Color[2] - vlcur->Color[2]) * lfactor) >> 12);
s64 perspfactorl1 = ((s64)(0x1000 - lfactor) << 12) / scrcoords[lcur][3];
s64 perspfactorl2 = ((s64)lfactor << 12) / scrcoords[lnext][3];
s64 perspfactorr1 = ((s64)(0x1000 - rfactor) << 12) / scrcoords[rcur][3];
s64 perspfactorr2 = ((s64)rfactor << 12) / scrcoords[rnext][3];
u8 rr = vrcur->Color[0] + (((vrnext->Color[0] - vrcur->Color[0]) * rfactor) >> 12);
u8 gr = vrcur->Color[1] + (((vrnext->Color[1] - vrcur->Color[1]) * rfactor) >> 12);
u8 br = vrcur->Color[2] + (((vrnext->Color[2] - vrcur->Color[2]) * rfactor) >> 12);
u32 rl = (((perspfactorl1 * vlcur->Color[0]) + (perspfactorl2 * vlnext->Color[0])) << 12) / (perspfactorl1 + perspfactorl2);
u32 gl = (((perspfactorl1 * vlcur->Color[1]) + (perspfactorl2 * vlnext->Color[1])) << 12) / (perspfactorl1 + perspfactorl2);
u32 bl = (((perspfactorl1 * vlcur->Color[2]) + (perspfactorl2 * vlnext->Color[2])) << 12) / (perspfactorl1 + perspfactorl2);
u32 rr = (((perspfactorr1 * vrcur->Color[0]) + (perspfactorr2 * vrnext->Color[0])) << 12) / (perspfactorr1 + perspfactorr2);
u32 gr = (((perspfactorr1 * vrcur->Color[1]) + (perspfactorr2 * vrnext->Color[1])) << 12) / (perspfactorr1 + perspfactorr2);
u32 br = (((perspfactorr1 * vrcur->Color[2]) + (perspfactorr2 * vrnext->Color[2])) << 12) / (perspfactorr1 + perspfactorr2);
s32 xdiv;
if (xr == xl)
@ -270,29 +265,15 @@ void RenderPolygon(Polygon* polygon)
s32 z = zl + (((s64)(zr - zl) * xfactor) >> 12);
//s32 z = (((zr - zl) * xfactor) >> 12);
//if (zr!=zl) z = (z << 12) / (zr - zl);
//s32 w = wl + (((s64)(wr - wl) * xfactor) >> 12);
//w >>= 12;
//if (w!=0) xfactor = ((s64)xfactor * 0xFFFFFF) / w;
//xfactor = (xfactor * w) >> 12;
//s32 z_inv = ((z>>12)==0) ? 0x1000 : 0x1000000 / (z >> 12);
//xfactor = (xfactor * z_inv) >> 12;
//if (z) xfactor = (xfactor << 12) / z;
// TODO: get rid of this shit
if (x<0 || x>255 || y<0 || y>191)
{
//printf("BAD COORDS!! %d %d\n", x, y);
x = 0; y = 0;
}
s32 perspfactor1 = ((0x1000 - xfactor) << 12) / wl;
s32 perspfactor2 = (xfactor << 12) / wr;
// possible optimization: only do color interpolation if the depth test passes
u8 vr = rl + (((rr - rl) * xfactor) >> 12);
u8 vg = gl + (((gr - gl) * xfactor) >> 12);
u8 vb = bl + (((br - bl) * xfactor) >> 12);
RenderPixel(polygon->Attr, x, y, z, vr, vg, vb);
u32 vr = (s64)((perspfactor1 * rl) + (perspfactor2 * rr)) / (perspfactor1 + perspfactor2);
u32 vg = (s64)((perspfactor1 * gl) + (perspfactor2 * gr)) / (perspfactor1 + perspfactor2);
u32 vb = (s64)((perspfactor1 * bl) + (perspfactor2 * br)) / (perspfactor1 + perspfactor2);
RenderPixel(polygon->Attr, x, y, z, vr>>12, vg>>12, vb>>12);
// Z debug
/*u8 zerp = (w * 63) / 0xFFFFFF;

View File

@ -1,5 +1,5 @@
# depslib dependency file v1.0
1487105574 source:c:\documents\sources\melonds\main.cpp
1487173011 source:c:\documents\sources\melonds\main.cpp
<stdio.h>
<windows.h>
"NDS.h"
@ -10,7 +10,7 @@
1481161027 c:\documents\sources\melonds\types.h
1487101361 source:c:\documents\sources\melonds\nds.cpp
1487177244 source:c:\documents\sources\melonds\nds.cpp
<stdio.h>
<string.h>
"NDS.h"
@ -155,7 +155,7 @@
"GPU.h"
"FIFO.h"
1487039203 source:c:\documents\sources\melonds\gpu3d_soft.cpp
1487177182 source:c:\documents\sources\melonds\gpu3d_soft.cpp
<stdio.h>
<string.h>
"NDS.h"