/*
===================
R_ClipTriangleToLight
Returns false if nothing is left after clipping
===================
*/
ID_STATIC_TEMPLATE ID_INLINE bool R_ClipTriangleToLight( stencilRef_t *st, const idVec3 &a, const idVec3 &b, const idVec3 &c, int planeBits, const idPlane frustum[6] ) {
int i;
int base;
clipTri_t pingPong[2], *ct;
int p;
pingPong[0].numVerts = 3;
pingPong[0].edgeFlags[0] = 0;
pingPong[0].edgeFlags[1] = 0;
pingPong[0].edgeFlags[2] = 0;
pingPong[0].verts[0] = a;
pingPong[0].verts[1] = b;
pingPong[0].verts[2] = c;
p = 0;
for( i = 0; i < 6; i++ ) {
if( planeBits & ( 1 << i ) ) {
p = R_ChopWinding( pingPong, p, frustum[i] );
if( pingPong[p].numVerts < 1 ) {
return false;
}
}
}
ct = &pingPong[p];
// copy the clipped points out to shadowVerts
if( st->numShadowVerts + ct->numVerts * 2 > MAX_SHADOW_VERTS ) {
st->overflowed = true;
return false;
}
base = st->numShadowVerts;
for( i = 0; i < ct->numVerts; i++ ) {
st->shadowVerts[base + i * 2].ToVec3() = ct->verts[i];
}
st->numShadowVerts += ct->numVerts * 2;
if( st->numShadowIndexes + 3 * ( ct->numVerts - 2 ) > MAX_SHADOW_INDEXES ) {
st->overflowed = true;
return false;
}
for( i = 2; i < ct->numVerts; i++ ) {
st->shadowIndexes[st->numShadowIndexes++] = base + i * 2;
st->shadowIndexes[st->numShadowIndexes++] = base + ( i - 1 ) * 2;
st->shadowIndexes[st->numShadowIndexes++] = base;
}
// any edges that were created by the clipping process will
// have a silhouette quad created for it, because it is one
// of the exterior bounds of the shadow volume
for( i = 0; i < ct->numVerts; i++ ) {
if( ct->edgeFlags[i] ) {
if( st->numClipSilEdges == MAX_CLIP_SIL_EDGES ) {
break;
}
st->clipSilEdges[st->numClipSilEdges][0] = base + i * 2;
if( i == ct->numVerts - 1 ) {
st->clipSilEdges[st->numClipSilEdges][1] = base;
} else {
st->clipSilEdges[st->numClipSilEdges][1] = base + ( i + 1 ) * 2;
}
st->numClipSilEdges++;
}
}
return true;
}
/*
===================
R_ClipTriangleToLight
Returns false if nothing is left after clipping
===================
*/
static bool R_ClipTriangleToLight( const idVec3 &a, const idVec3 &b, const idVec3 &c, int planeBits, const idPlane frustum[6] ) {
int i;
clipTri_t pingPong[2];
int p;
pingPong[0].numVerts = 3;
pingPong[0].verts[0] = a;
pingPong[0].verts[1] = b;
pingPong[0].verts[2] = c;
p = 0;
for ( i = 0 ; i < 6 ; i++ ) {
if ( planeBits & ( 1 << i ) ) {
p = R_ChopWinding( pingPong, p, frustum[i] );
if ( pingPong[p].numVerts < 1 ) {
return false;
}
}
}
return true;
}
