Commit 68fb77b2 authored by StapleButter's avatar StapleButter
Browse files

* backface/frontface culling (and rendering of backfacing polygons)

* fix clipping/viewport transform precision errors
* triangle/quad strips
parent fb53fd51
......@@ -159,9 +159,14 @@ u32 PolygonMode;
s16 CurVertex[3];
u8 VertexColor[3];
u32 PolygonAttr;
u32 CurPolygonAttr;
Vertex TempVertexBuffer[4];
u32 VertexNum;
u32 VertexNumInPoly;
u32 NumConsecutivePolygons;
Polygon* LastStripPolygon;
Vertex VertexRAM[6144 * 2];
Polygon PolygonRAM[2048 * 2];
......@@ -385,13 +390,13 @@ void UpdateClipMatrix()
template<int comp, s32 plane>
void ClipSegment(Vertex* outbuf, int num, Vertex* vout, Vertex* vin)
void ClipSegment(Vertex* outbuf, Vertex* vout, Vertex* vin)
{
s64 factor = ((vin->Position[3] - (plane*vin->Position[comp])) << 12) /
s64 factor = ((s64)(vin->Position[3] - (plane*vin->Position[comp])) << 24) /
((vin->Position[3] - (plane*vin->Position[comp])) - (vout->Position[3] - (plane*vout->Position[comp])));
Vertex mid;
#define INTERPOLATE(var) mid.var = vin->var + (((vout->var - vin->var) * factor) >> 12);
#define INTERPOLATE(var) mid.var = vin->var + (((vout->var - vin->var) * factor) >> 24);
INTERPOLATE(Position[0]);
INTERPOLATE(Position[1]);
......@@ -402,213 +407,339 @@ void ClipSegment(Vertex* outbuf, int num, Vertex* vout, Vertex* vin)
INTERPOLATE(Color[1]);
INTERPOLATE(Color[2]);
mid.Clipped = true;
#undef INTERPOLATE
outbuf[num] = mid;
*outbuf = mid;
}
void SubmitPolygon()
{
// clip.
// for each vertex:
// if it's outside, check if the previous and next vertices are inside, if so, fixor
Vertex clippedvertices[2][10];
u32 numclipped;
Vertex* reusedvertices[2];
int clipstart = 0;
int lastpolyverts = 0;
int nverts = PolygonMode & 0x1 ? 4:3;
int nvisible = 0;
int prev, next;
int c;
/*if (NumPolygons == 91)
for (int i = 0; i < nverts; i++)
// culling
//if (!(TempVertexBuffer[0].Color[0]==0 && TempVertexBuffer[0].Color[1]==63 && TempVertexBuffer[0].Color[2]==63))
// return;
// checkme: does it work this way for quads and up?
/*s32 _x1 = TempVertexBuffer[1].Position[0] - TempVertexBuffer[0].Position[0];
s32 _x2 = TempVertexBuffer[2].Position[0] - TempVertexBuffer[0].Position[0];
s32 _y1 = TempVertexBuffer[1].Position[1] - TempVertexBuffer[0].Position[1];
s32 _y2 = TempVertexBuffer[2].Position[1] - TempVertexBuffer[0].Position[1];
s32 _z1 = TempVertexBuffer[1].Position[2] - TempVertexBuffer[0].Position[2];
s32 _z2 = TempVertexBuffer[2].Position[2] - TempVertexBuffer[0].Position[2];
s32 normalX = (((s64)_y1 * _z2) - ((s64)_z1 * _y2)) >> 12;
s32 normalY = (((s64)_z1 * _x2) - ((s64)_x1 * _z2)) >> 12;
s32 normalZ = (((s64)_x1 * _y2) - ((s64)_y1 * _x2)) >> 12;*/
/*s32 centerX = ((s64)TempVertexBuffer[0].Position[3] * ClipMatrix[12]) >> 12;
s32 centerY = ((s64)TempVertexBuffer[0].Position[3] * ClipMatrix[13]) >> 12;
s32 centerZ = ((s64)TempVertexBuffer[0].Position[3] * ClipMatrix[14]) >> 12;*/
/*s64 dot = ((s64)(-TempVertexBuffer[0].Position[0]) * normalX) +
((s64)(-TempVertexBuffer[0].Position[1]) * normalY) +
((s64)(-TempVertexBuffer[0].Position[2]) * normalZ); // checkme*/
// code inspired from Dolphin's software renderer.
// maybe not 100% right
s32 _x0 = TempVertexBuffer[0].Position[0];
s32 _x1 = TempVertexBuffer[1].Position[0];
s32 _x2 = TempVertexBuffer[2].Position[0];
s32 _y0 = TempVertexBuffer[0].Position[1];
s32 _y1 = TempVertexBuffer[1].Position[1];
s32 _y2 = TempVertexBuffer[2].Position[1];
s32 _z0 = TempVertexBuffer[0].Position[3];
s32 _z1 = TempVertexBuffer[1].Position[3];
s32 _z2 = TempVertexBuffer[2].Position[3];
s32 normalX = (((s64)_y0 * _z2) - ((s64)_z0 * _y2)) >> 12;
s32 normalY = (((s64)_z0 * _x2) - ((s64)_x0 * _z2)) >> 12;
s32 normalZ = (((s64)_x0 * _y2) - ((s64)_y0 * _x2)) >> 12;
s64 dot = ((s64)_x1 * normalX) + ((s64)_y1 * normalY) + ((s64)_z1 * normalZ);
bool facingview = (dot < 0);
//printf("Z: %d %d\n", normalZ, -TempVertexBuffer[0].Position[2]);
if (facingview)
{
Vertex vtx = TempVertexBuffer[i];
printf("pre-clip v%d: %f %f %f %f\n", i,
vtx.Position[0]/4096.0f, vtx.Position[1]/4096.0f,
vtx.Position[2]/4096.0f, vtx.Position[3]/4096.0f);
}*/
if (!(CurPolygonAttr & (1<<7)))
{
LastStripPolygon = NULL;
return;
}
}
else
{
if (!(CurPolygonAttr & (1<<6)))
{
LastStripPolygon = NULL;
return;
}
}
// for strips, check whether we can attach to the previous polygon
// this requires two vertices shared with the previous polygon, and that
// the two polygons be of the same type
if (PolygonMode >= 2 && LastStripPolygon)
{
int id0, id1;
if (PolygonMode == 2)
{
if (NumConsecutivePolygons & 1)
{
id0 = 2;
id1 = 1;
}
else
{
id0 = 0;
id1 = 2;
}
lastpolyverts = 3;
}
else
{
id0 = 3;
id1 = 2;
lastpolyverts = 4;
}
if (LastStripPolygon->NumVertices == lastpolyverts &&
!LastStripPolygon->Vertices[id0]->Clipped &&
!LastStripPolygon->Vertices[id1]->Clipped)
{
reusedvertices[0] = LastStripPolygon->Vertices[id0];
reusedvertices[1] = LastStripPolygon->Vertices[id1];
clippedvertices[0][0] = *reusedvertices[0];
clippedvertices[0][1] = *reusedvertices[1];
clippedvertices[1][0] = *reusedvertices[0];
clippedvertices[1][1] = *reusedvertices[1];
clipstart = 2;
}
}
// clip.
// for each vertex:
// if it's outside, check if the previous and next vertices are inside
// if so, place a new vertex at the edge of the view volume
// X clipping
prev = nverts-1; next = 1; c = 0;
for (int i = 0; i < nverts; i++)
c = clipstart;
for (int i = clipstart; i < nverts; i++)
{
prev = i-1; if (prev < 0) prev = nverts-1;
next = i+1; if (next >= nverts) next = 0;
Vertex vtx = TempVertexBuffer[i];
if (vtx.Position[0] > vtx.Position[3])
{
Vertex* vprev = &TempVertexBuffer[prev];
if (vprev->Position[0] <= vprev->Position[3])
{
ClipSegment<0, 1>(clippedvertices[0], c, &vtx, vprev);
ClipSegment<0, 1>(&clippedvertices[0][c], &vtx, vprev);
c++;
}
Vertex* vnext = &TempVertexBuffer[next];
if (vnext->Position[0] <= vnext->Position[3])
{
ClipSegment<0, 1>(clippedvertices[0], c, &vtx, vnext);
ClipSegment<0, 1>(&clippedvertices[0][c], &vtx, vnext);
c++;
}
}
else
clippedvertices[0][c++] = vtx;
prev++; if (prev >= nverts) prev = 0;
next++; if (next >= nverts) next = 0;
}
nverts = c; prev = nverts-1; next = 1; c = 0;
for (int i = 0; i < nverts; i++)
nverts = c; c = clipstart;
for (int i = clipstart; i < nverts; i++)
{
prev = i-1; if (prev < 0) prev = nverts-1;
next = i+1; if (next >= nverts) next = 0;
Vertex vtx = clippedvertices[0][i];
if (vtx.Position[0] < -vtx.Position[3])
{
Vertex* vprev = &clippedvertices[0][prev];
if (vprev->Position[0] >= -vprev->Position[3])
{
ClipSegment<0, -1>(clippedvertices[1], c, &vtx, vprev);
ClipSegment<0, -1>(&clippedvertices[1][c], &vtx, vprev);
c++;
}
Vertex* vnext = &clippedvertices[0][next];
if (vnext->Position[0] >= -vnext->Position[3])
{
ClipSegment<0, -1>(clippedvertices[1], c, &vtx, vnext);
ClipSegment<0, -1>(&clippedvertices[1][c], &vtx, vnext);
c++;
}
}
else
clippedvertices[1][c++] = vtx;
prev++; if (prev >= nverts) prev = 0;
next++; if (next >= nverts) next = 0;
}
// Y clipping
nverts = c; prev = nverts-1; next = 1; c = 0;
for (int i = 0; i < nverts; i++)
nverts = c; c = clipstart;
for (int i = clipstart; i < nverts; i++)
{
prev = i-1; if (prev < 0) prev = nverts-1;
next = i+1; if (next >= nverts) next = 0;
Vertex vtx = clippedvertices[1][i];
if (vtx.Position[1] > vtx.Position[3])
{
Vertex* vprev = &clippedvertices[1][prev];
if (vprev->Position[1] <= vprev->Position[3])
{
ClipSegment<1, 1>(clippedvertices[0], c, &vtx, vprev);
ClipSegment<1, 1>(&clippedvertices[0][c], &vtx, vprev);
c++;
}
Vertex* vnext = &clippedvertices[1][next];
if (vnext->Position[1] <= vnext->Position[3])
{
ClipSegment<1, 1>(clippedvertices[0], c, &vtx, vnext);
ClipSegment<1, 1>(&clippedvertices[0][c], &vtx, vnext);
c++;
}
}
else
clippedvertices[0][c++] = vtx;
prev++; if (prev >= nverts) prev = 0;
next++; if (next >= nverts) next = 0;
}
nverts = c; prev = nverts-1; next = 1; c = 0;
for (int i = 0; i < nverts; i++)
nverts = c; c = clipstart;
for (int i = clipstart; i < nverts; i++)
{
prev = i-1; if (prev < 0) prev = nverts-1;
next = i+1; if (next >= nverts) next = 0;
Vertex vtx = clippedvertices[0][i];
if (vtx.Position[1] < -vtx.Position[3])
{
Vertex* vprev = &clippedvertices[0][prev];
if (vprev->Position[1] >= -vprev->Position[3])
{
ClipSegment<1, -1>(clippedvertices[1], c, &vtx, vprev);
ClipSegment<1, -1>(&clippedvertices[1][c], &vtx, vprev);
c++;
}
Vertex* vnext = &clippedvertices[0][next];
if (vnext->Position[1] >= -vnext->Position[3])
{
ClipSegment<1, -1>(clippedvertices[1], c, &vtx, vnext);
ClipSegment<1, -1>(&clippedvertices[1][c], &vtx, vnext);
c++;
}
}
else
clippedvertices[1][c++] = vtx;
prev++; if (prev >= nverts) prev = 0;
next++; if (next >= nverts) next = 0;
}
// Z clipping
nverts = c; prev = nverts-1; next = 1; c = 0;
for (int i = 0; i < nverts; i++)
nverts = c; c = clipstart;
for (int i = clipstart; i < nverts; i++)
{
prev = i-1; if (prev < 0) prev = nverts-1;
next = i+1; if (next >= nverts) next = 0;
Vertex vtx = clippedvertices[1][i];
if (vtx.Position[2] > vtx.Position[3])
{
Vertex* vprev = &clippedvertices[1][prev];
if (vprev->Position[2] <= vprev->Position[3])
{
ClipSegment<2, 1>(clippedvertices[0], c, &vtx, vprev);
ClipSegment<2, 1>(&clippedvertices[0][c], &vtx, vprev);
c++;
}
Vertex* vnext = &clippedvertices[1][next];
if (vnext->Position[2] <= vnext->Position[3])
{
ClipSegment<2, 1>(clippedvertices[0], c, &vtx, vnext);
ClipSegment<2, 1>(&clippedvertices[0][c], &vtx, vnext);
c++;
}
}
else
clippedvertices[0][c++] = vtx;
prev++; if (prev >= nverts) prev = 0;
next++; if (next >= nverts) next = 0;
}
nverts = c; prev = nverts-1; next = 1; c = 0;
for (int i = 0; i < nverts; i++)
nverts = c; c = clipstart;
for (int i = clipstart; i < nverts; i++)
{
prev = i-1; if (prev < 0) prev = nverts-1;
next = i+1; if (next >= nverts) next = 0;
Vertex vtx = clippedvertices[0][i];
if (vtx.Position[2] < -vtx.Position[3])
{
Vertex* vprev = &clippedvertices[0][prev];
if (vprev->Position[2] >= -vprev->Position[3])
{
ClipSegment<2, -1>(clippedvertices[1], c, &vtx, vprev);
ClipSegment<2, -1>(&clippedvertices[1][c], &vtx, vprev);
c++;
}
Vertex* vnext = &clippedvertices[0][next];
if (vnext->Position[2] >= -vnext->Position[3])
{
ClipSegment<2, -1>(clippedvertices[1], c, &vtx, vnext);
ClipSegment<2, -1>(&clippedvertices[1][c], &vtx, vnext);
c++;
}
}
else
clippedvertices[1][c++] = vtx;
prev++; if (prev >= nverts) prev = 0;
next++; if (next >= nverts) next = 0;
}
if (c == 0) return;
if (c == 0)
{
LastStripPolygon = NULL;
return;
}
// build the actual polygon
// TODO: tri/quad strips
if (NumPolygons >= 2048) return;
if (NumVertices+c > 6144) return;
if (NumPolygons >= 2048 || NumVertices+c > 6144)
{
LastStripPolygon = NULL;
return;
}
Polygon* poly = &CurPolygonRAM[NumPolygons++];
poly->NumVertices = 0;
for (int i = 0; i < c; i++)
poly->Attr = CurPolygonAttr;
poly->FacingView = facingview;
if (LastStripPolygon && clipstart > 0)
{
if (c == lastpolyverts)
{
poly->Vertices[0] = reusedvertices[0];
poly->Vertices[1] = reusedvertices[1];
}
else
{
Vertex v0 = *reusedvertices[0];
Vertex v1 = *reusedvertices[1];
CurVertexRAM[NumVertices] = v0;
poly->Vertices[0] = &CurVertexRAM[NumVertices];
CurVertexRAM[NumVertices+1] = v1;
poly->Vertices[1] = &CurVertexRAM[NumVertices+1];
NumVertices += 2;
}
poly->NumVertices += 2;
}
for (int i = clipstart; i < c; i++)
{
CurVertexRAM[NumVertices] = clippedvertices[1][i];
poly->Vertices[i] = &CurVertexRAM[NumVertices];
......@@ -616,77 +747,29 @@ void SubmitPolygon()
NumVertices++;
poly->NumVertices++;
}
if (PolygonMode >= 2)
LastStripPolygon = poly;
else
LastStripPolygon = NULL;
}
void SubmitVertex()
{
s64 vertex[4] = {(s64)CurVertex[0], (s64)CurVertex[1], (s64)CurVertex[2], 0x1000};
//s32 vertextrans[4];
Vertex* vertextrans = &TempVertexBuffer[VertexNumInPoly];
if (PolygonMode & 0x2) return;
//printf("vertex: %f %f %f\n", vertex[0]/4096.0f, vertex[1]/4096.0f, vertex[2]/4096.0f);
UpdateClipMatrix();
vertextrans->Position[0] = (vertex[0]*ClipMatrix[0] + vertex[1]*ClipMatrix[4] + vertex[2]*ClipMatrix[8] + vertex[3]*ClipMatrix[12]) >> 12;
vertextrans->Position[1] = (vertex[0]*ClipMatrix[1] + vertex[1]*ClipMatrix[5] + vertex[2]*ClipMatrix[9] + vertex[3]*ClipMatrix[13]) >> 12;
vertextrans->Position[2] = (vertex[0]*ClipMatrix[2] + vertex[1]*ClipMatrix[6] + vertex[2]*ClipMatrix[10] + vertex[3]*ClipMatrix[14]) >> 12;
vertextrans->Position[3] = (vertex[0]*ClipMatrix[3] + vertex[1]*ClipMatrix[7] + vertex[2]*ClipMatrix[11] + vertex[3]*ClipMatrix[15]) >> 12;
/*printf("vertex fart: %f %f %f %f\n",
vertextrans->Position[0]/4096.0f,
vertextrans->Position[1]/4096.0f,
vertextrans->Position[2]/4096.0f,
vertextrans->Position[3]/4096.0f);*/
/*s32 w_inv;
if (vertextrans->Position[3] == 0)
w_inv = 0x1000; // checkme
else if(vertextrans->Position[3] < 0)
w_inv = 0x1000000 / -vertextrans->Position[3];
else
w_inv = 0x1000000 / vertextrans->Position[3];
vertextrans->Position[0] = (vertextrans->Position[0] * w_inv) >> 12;
vertextrans->Position[1] = (vertextrans->Position[1] * w_inv) >> 12;
vertextrans->Position[2] = (vertextrans->Position[2] * w_inv) >> 12;*/
vertextrans->Color[0] = VertexColor[0];
vertextrans->Color[1] = VertexColor[1];
vertextrans->Color[2] = VertexColor[2];
/*printf("vertex trans: %f %f %f %f\n",
vertextrans->Position[0]/4096.0f,
vertextrans->Position[1]/4096.0f,
vertextrans->Position[2]/4096.0f,
vertextrans->Position[3]/4096.0f);
printf("clip: %f %f %f %f\n",
ClipMatrix[3]/4096.0f,
ClipMatrix[7]/4096.0f,
ClipMatrix[11]/4096.0f,
ClipMatrix[15]/4096.0f);*/
/*if (vertextrans[3] == 0)
{
//printf("!!!! VERTEX W IS ZERO\n");
//return;
vertextrans[3] = 0x1000; // checkme
}
s32 screenX = (((vertextrans[0]+vertextrans[3]) * Viewport[2]) / (vertextrans[3]<<1)) + Viewport[0];
s32 screenY = (((vertextrans[1]+vertextrans[3]) * Viewport[3]) / (vertextrans[3]<<1)) + Viewport[1];
printf("screen: %d, %d\n", screenX, screenY);
s32* finalvertex = TempVertexBuffer[VertexNumInPoly];
finalvertex[0] = screenX;
finalvertex[1] = screenY;
finalvertex[2] = vertextrans[2];
finalvertex[3] = vertextrans[3];*/
// triangle strip: 0,1,2 1,2,3 2,3,4 3,4,5 ...
// quad strip: 0,1,3,2 2,3,5,4 4,5,7,6 6,7,9,8 ...
vertextrans->Clipped = false;
VertexNum++;
VertexNumInPoly++;
......@@ -698,6 +781,7 @@ void SubmitVertex()
{
VertexNumInPoly = 0;
SubmitPolygon();
NumConsecutivePolygons++;
}
break;
......@@ -706,32 +790,49 @@ void SubmitVertex()
{
VertexNumInPoly = 0;
SubmitPolygon();
NumConsecutivePolygons++;
}
break;
/*case 2: // triangle strip
if (VertexNum > 3)
case 2: // triangle strip
if (NumConsecutivePolygons & 1)
{
if (VertexNumInPoly == 1)
{
VertexNumInPoly = 0;
// reorder
}
else
VertexNumInPoly = 0;
Vertex tmp = TempVertexBuffer[1];
TempVertexBuffer[1] = TempVertexBuffer[0];
TempVertexBuffer[0] = tmp;
VertexNumInPoly = 2;
SubmitPolygon();
NumConsecutivePolygons++;
TempVertexBuffer[1] = TempVertexBuffer[2];
}
else if (VertexNum == 3)
else if (VertexNumInPoly == 3)
{
VertexNumInPoly = 2;
SubmitPolygon();
NumConsecutivePolygons++;
TempVertexBuffer[0] = TempVertexBuffer[1];
TempVertexBuffer[1] = TempVertexBuffer[2];
}
break;*/
default: VertexNumInPoly = 0; break;
break;
case 3: // quad strip
if (VertexNumInPoly == 4)
{
Vertex tmp = TempVertexBuffer[3];
TempVertexBuffer[3] = TempVertexBuffer[2];
TempVertexBuffer[2] = tmp;
VertexNumInPoly = 2;
SubmitPolygon();
NumConsecutivePolygons++;
TempVertexBuffer[0] = TempVertexBuffer[3];
TempVertexBuffer[1] = TempVertexBuffer[2];
}
break;
}
}
......@@ -791,7 +892,7 @@ void ExecuteCommand()
if (ExecParamCount >= CmdNumParams[entry.Command])
{
//CycleCount += CmdNumCycles[entry.Command];
CycleCount += CmdNumCycles[entry.Command];
ExecParamCount = 0;
GXStat &= ~(1<<14);
......@@ -1127,10 +1228,17 @@ void ExecuteCommand()
SubmitVertex();
break;
case 0x29: // polygon attributes
PolygonAttr = ExecParams[0];
break;
case 0x40:
PolygonMode = ExecParams[0] & 0x3;
VertexNum = 0;
VertexNumInPoly = 0;
NumConsecutivePolygons = 0;
LastStripPolygon = NULL;
CurPolygonAttr = PolygonAttr;
break;
case 0x50:
......
......@@ -27,6 +27,8 @@ typedef struct
s32 Position[4];
u8 Color[3];
bool Clipped;