/* Clip a triangle against the viewport and user clip planes.
*/
static void TAG(clip_draw_triangle)( GLcontext *ctx,
TNL_VERTEX *v0,
TNL_VERTEX *v1,
TNL_VERTEX *v2,
GLuint mask )
{
LOCAL_VARS;
GET_INTERP_FUNC;
TNL_VERTEX tmp[MAX_CLIPPED_VERTICES];
TNL_VERTEX *verts = tmp;
TNL_VERTEX *(inlist[2][MAX_CLIPPED_VERTICES]);
TNL_VERTEX **out;
GLuint in = 0;
GLuint n = 3;
GLuint i;
ASSIGN_3V(inlist, v2, v0, v1 ); /* pv rotated to slot zero */
POLY_CLIP( CLIP_RIGHT_BIT, -1, 0, 0, 1 );
POLY_CLIP( CLIP_LEFT_BIT, 1, 0, 0, 1 );
POLY_CLIP( CLIP_TOP_BIT, 0, -1, 0, 1 );
POLY_CLIP( CLIP_BOTTOM_BIT, 0, 1, 0, 1 );
POLY_CLIP( CLIP_FAR_BIT, 0, 0, -1, 1 );
POLY_CLIP( CLIP_NEAR_BIT, 0, 0, 1, 1 );
if ((ctx->_TriangleCaps & DD_FLATSHADE) && v2 != inlist[0])
COPY_PV( ctx, inlist[0], v2 );
out = inlist[in];
DRAW_POLYGON( out, n );
}
static void ClipTriangle(int *indices, int* numIndices)
{
int mask = 0;
mask |= CalcClipMask(Vertices[0]);
mask |= CalcClipMask(Vertices[1]);
mask |= CalcClipMask(Vertices[2]);
if (mask != 0)
{
for (int i = 0; i < 3; i += 3)
{
int vlist[2][2*6+1];
int *inlist = vlist[0], *outlist = vlist[1];
int n = 3;
int numVertices = 3;
inlist[0] = 0;
inlist[1] = 1;
inlist[2] = 2;
// mark this triangle as unused in case it should be completely
// clipped
indices[0] = SKIP_FLAG;
indices[1] = SKIP_FLAG;
indices[2] = SKIP_FLAG;
POLY_CLIP(CLIP_POS_X_BIT, -1, 0, 0, 1);
POLY_CLIP(CLIP_NEG_X_BIT, 1, 0, 0, 1);
POLY_CLIP(CLIP_POS_Y_BIT, 0, -1, 0, 1);
POLY_CLIP(CLIP_NEG_Y_BIT, 0, 1, 0, 1);
POLY_CLIP(CLIP_POS_Z_BIT, 0, 0, 0, 1);
POLY_CLIP(CLIP_NEG_Z_BIT, 0, 0, 1, 1);
INCSTAT(stats.thisFrame.numTrianglesClipped);
// transform the poly in inlist into triangles
indices[0] = inlist[0];
indices[1] = inlist[1];
indices[2] = inlist[2];
for (int j = 3; j < n; ++j)
{
indices[(*numIndices)++] = inlist[0];
indices[(*numIndices)++] = inlist[j - 1];
indices[(*numIndices)++] = inlist[j];
}
}
}
}
void ProcessTriangle(VertexData& v0, VertexData& v1, VertexData& v2, const VertexData &provoking) {
if (gstate.isModeThrough()) {
// In case of cull reordering, make sure the right color is on the final vertex.
if (gstate.getShadeMode() == GE_SHADE_FLAT) {
VertexData corrected2 = v2;
corrected2.color0 = provoking.color0;
corrected2.color1 = provoking.color1;
Rasterizer::DrawTriangle(v0, v1, corrected2);
} else {
Rasterizer::DrawTriangle(v0, v1, v2);
}
return;
}
enum { NUM_CLIPPED_VERTICES = 33, NUM_INDICES = NUM_CLIPPED_VERTICES + 3 };
VertexData* Vertices[NUM_INDICES];
VertexData ClippedVertices[NUM_CLIPPED_VERTICES];
for (int i = 0; i < NUM_CLIPPED_VERTICES; ++i)
Vertices[i+3] = &ClippedVertices[i];
// TODO: Change logic when it's a backface (why? In what way?)
Vertices[0] = &v0;
Vertices[1] = &v1;
Vertices[2] = &v2;
int indices[NUM_INDICES] = { 0, 1, 2, SKIP_FLAG, SKIP_FLAG, SKIP_FLAG, SKIP_FLAG, SKIP_FLAG, SKIP_FLAG,
SKIP_FLAG, SKIP_FLAG, SKIP_FLAG, SKIP_FLAG, SKIP_FLAG, SKIP_FLAG,
SKIP_FLAG, SKIP_FLAG, SKIP_FLAG, SKIP_FLAG, SKIP_FLAG, SKIP_FLAG };
int numIndices = 3;
int mask = 0;
mask |= CalcClipMask(v0.clippos);
mask |= CalcClipMask(v1.clippos);
mask |= CalcClipMask(v2.clippos);
if (mask) {
for (int i = 0; i < 3; i += 3) {
int vlist[2][2*6+1];
int *inlist = vlist[0], *outlist = vlist[1];
int n = 3;
int numVertices = 3;
inlist[0] = 0;
inlist[1] = 1;
inlist[2] = 2;
// mark this triangle as unused in case it should be completely clipped
indices[0] = SKIP_FLAG;
indices[1] = SKIP_FLAG;
indices[2] = SKIP_FLAG;
POLY_CLIP(CLIP_POS_X_BIT, -1, 0, 0, 1);
POLY_CLIP(CLIP_NEG_X_BIT, 1, 0, 0, 1);
POLY_CLIP(CLIP_POS_Y_BIT, 0, -1, 0, 1);
POLY_CLIP(CLIP_NEG_Y_BIT, 0, 1, 0, 1);
POLY_CLIP(CLIP_POS_Z_BIT, 0, 0, 0, 1);
POLY_CLIP(CLIP_NEG_Z_BIT, 0, 0, 1, 1);
// transform the poly in inlist into triangles
indices[0] = inlist[0];
indices[1] = inlist[1];
indices[2] = inlist[2];
for (int j = 3; j < n; ++j) {
indices[numIndices++] = inlist[0];
indices[numIndices++] = inlist[j - 1];
indices[numIndices++] = inlist[j];
}
}
} else if (CalcClipMask(v0.clippos) & CalcClipMask(v1.clippos) & CalcClipMask(v2.clippos)) {
// If clipping is disabled, only discard the current primitive
// if all three vertices lie outside one of the clipping planes
return;
}
for (int i = 0; i + 3 <= numIndices; i += 3) {
if (indices[i] != SKIP_FLAG) {
VertexData data[3] = { *Vertices[indices[i]], *Vertices[indices[i+1]], *Vertices[indices[i+2]] };
data[0].screenpos = TransformUnit::ClipToScreen(data[0].clippos);
data[1].screenpos = TransformUnit::ClipToScreen(data[1].clippos);
data[2].screenpos = TransformUnit::ClipToScreen(data[2].clippos);
if (gstate.getShadeMode() == GE_SHADE_FLAT) {
// So that the order of clipping doesn't matter...
data[2].color0 = provoking.color0;
data[2].color1 = provoking.color1;
}
Rasterizer::DrawTriangle(data[0], data[1], data[2]);
}
}
}
void ProcessTriangle(VertexData& v0, VertexData& v1, VertexData& v2)
{
if (gstate.isModeThrough()) {
Rasterizer::DrawTriangle(v0, v1, v2);
return;
}
enum { NUM_CLIPPED_VERTICES = 33, NUM_INDICES = NUM_CLIPPED_VERTICES + 3 };
VertexData* Vertices[NUM_INDICES];
VertexData ClippedVertices[NUM_CLIPPED_VERTICES];
for (int i = 0; i < NUM_CLIPPED_VERTICES; ++i)
Vertices[i+3] = &ClippedVertices[i];
// TODO: Change logic when it's a backface
Vertices[0] = &v0;
Vertices[1] = &v1;
Vertices[2] = &v2;
int indices[NUM_INDICES] = { 0, 1, 2, SKIP_FLAG, SKIP_FLAG, SKIP_FLAG, SKIP_FLAG, SKIP_FLAG, SKIP_FLAG,
SKIP_FLAG, SKIP_FLAG, SKIP_FLAG, SKIP_FLAG, SKIP_FLAG, SKIP_FLAG,
SKIP_FLAG, SKIP_FLAG, SKIP_FLAG, SKIP_FLAG, SKIP_FLAG, SKIP_FLAG };
int numIndices = 3;
int mask = 0;
mask |= CalcClipMask(v0.clippos);
mask |= CalcClipMask(v1.clippos);
mask |= CalcClipMask(v2.clippos);
if (mask && (gstate.clipEnable & 0x1)) {
// discard if any vertex is outside the near clipping plane
if (mask & CLIP_NEG_Z_BIT)
return;
for(int i = 0; i < 3; i += 3) {
int vlist[2][2*6+1];
int *inlist = vlist[0], *outlist = vlist[1];
int n = 3;
int numVertices = 3;
inlist[0] = 0;
inlist[1] = 1;
inlist[2] = 2;
// mark this triangle as unused in case it should be completely clipped
indices[0] = SKIP_FLAG;
indices[1] = SKIP_FLAG;
indices[2] = SKIP_FLAG;
POLY_CLIP(CLIP_POS_X_BIT, -1, 0, 0, 1);
POLY_CLIP(CLIP_NEG_X_BIT, 1, 0, 0, 1);
POLY_CLIP(CLIP_POS_Y_BIT, 0, -1, 0, 1);
POLY_CLIP(CLIP_NEG_Y_BIT, 0, 1, 0, 1);
POLY_CLIP(CLIP_POS_Z_BIT, 0, 0, 0, 1);
POLY_CLIP(CLIP_NEG_Z_BIT, 0, 0, 1, 1);
// transform the poly in inlist into triangles
indices[0] = inlist[0];
indices[1] = inlist[1];
indices[2] = inlist[2];
for (int j = 3; j < n; ++j) {
indices[numIndices++] = inlist[0];
indices[numIndices++] = inlist[j - 1];
indices[numIndices++] = inlist[j];
}
}
} else if (CalcClipMask(v0.clippos) & CalcClipMask(v1.clippos) & CalcClipMask(v2.clippos)) {
// If clipping is disabled, only discard the current primitive
// if all three vertices lie outside one of the clipping planes
return;
}
for(int i = 0; i+3 <= numIndices; i+=3)
{
if(indices[i] != SKIP_FLAG)
{
VertexData data[3] = { *Vertices[indices[i]], *Vertices[indices[i+1]], *Vertices[indices[i+2]] };
data[0].screenpos = TransformUnit::ClipToScreen(data[0].clippos);
data[1].screenpos = TransformUnit::ClipToScreen(data[1].clippos);
data[2].screenpos = TransformUnit::ClipToScreen(data[2].clippos);
Rasterizer::DrawTriangle(data[0], data[1], data[2]);
}
}
}
