Fix infinite loop in R_TerrainHeightForPoly

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smallmodel 2024-09-04 20:46:10 +02:00
parent 1e0195f6e3
commit c0d37c504a
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@ -1229,6 +1229,7 @@ qboolean R_TerrainHeightForPoly(cTerraPatchUnpacked_t *pPatch, polyVert_t *pVert
float x = pVerts->xyz[0];
float y = pVerts->xyz[1];
terraInt iTri;
// Calculate the average of the x and y coordinates of all vertices
if (nVerts > 1) {
@ -1243,24 +1244,10 @@ qboolean R_TerrainHeightForPoly(cTerraPatchUnpacked_t *pPatch, polyVert_t *pVert
}
// Get the first valid triangle in the patch
terraInt iTri = pPatch->drawinfo.iTriHead;
if (!iTri) {
assert(
!pPatch->drawinfo.iTriHead
&& va(
"R_TerrainHeightForPoly: point(%f %f) not in patch(%f %f %f)\n",
x,
y,
pPatch->x0,
pPatch->y0,
pPatch->z0
)
);
return qfalse;
}
iTri = pPatch->drawinfo.iTriHead;
// Find a triangle that contains the point (x, y)
while (qtrue) {
for(iTri = pPatch->drawinfo.iTriHead; iTri; iTri = g_pTris[iTri].iNext) {
if (g_pTris[iTri].byConstChecks & 4) {
// Get all three x-y coordinates of the current triangle's vertices
x0 = g_pVert[g_pTris[iTri].iPt[0]].xyz[0];
@ -1291,58 +1278,56 @@ qboolean R_TerrainHeightForPoly(cTerraPatchUnpacked_t *pPatch, polyVert_t *pVert
fAreaTotal = fArea[0] + fArea[1] + fArea[2];
if (fAreaTotal > 0.0) {
//
// Found it - the point is inside the triangle
break;
// Calculate the barycentric coordinates (fKx, fKy, fKz) of the triangle
//
float z0 = g_pVert[g_pTris[iTri].iPt[0]].xyz[2] / fAreaTotal;
float z1 = g_pVert[g_pTris[iTri].iPt[1]].xyz[2] / fAreaTotal;
float z2 = g_pVert[g_pTris[iTri].iPt[2]].xyz[2] / fAreaTotal;
fKy[0] = z0 * (x2 - x1);
fKy[1] = z1 * (x0 - x2);
fKy[2] = z2 * (x1 - x0);
fKx[0] = z0 * (y2 - y1);
fKx[1] = z1 * (y0 - y2);
fKx[2] = z2 * (y1 - y0);
// Note: this could be done with the CrossProduct macro if everything were in a vector
fKz[0] = fKx[0] * x1 - y1 * fKy[0];
fKz[1] = fKx[1] * x2 - y2 * fKy[1];
fKz[2] = fKx[2] * x0 - y0 * fKy[2];
// Calculate the height for each vertex
for (int i = 0; i < nVerts; i++) {
float fScaleX = pVerts[i].xyz[0] * (fKx[0] + fKx[1] + fKx[2]);
float fScaleY = pVerts[i].xyz[1] * (fKy[0] + fKy[1] + fKy[2]);
float fConstZ = fKz[0] + fKz[1] + fKz[2];
// Write back the calculated height into the vertex
pVerts[i].xyz[2] = fScaleY - fScaleX - fConstZ;
}
return qtrue;
}
}
iTri = g_pTris[iTri].iNext;
if (!iTri) {
// There's no triangle that contains point (x, y) - bail out
assert(
!g_pTris[iTri].iNext
&& va(
"R_TerrainHeightForPoly: point(%f %f) not in patch(%f %f %f)\n",
x,
y,
pPatch->x0,
pPatch->y0,
pPatch->z0
)
);
return qfalse;
}
}
// Calculate the barycentric coordinates (fKx, fKy, fKz) of the triangle
float z0 = g_pVert[g_pTris[iTri].iPt[0]].xyz[2] / fAreaTotal;
float z1 = g_pVert[g_pTris[iTri].iPt[1]].xyz[2] / fAreaTotal;
float z2 = g_pVert[g_pTris[iTri].iPt[2]].xyz[2] / fAreaTotal;
fKy[0] = z0 * (x2 - x1);
fKy[1] = z1 * (x0 - x2);
fKy[2] = z2 * (x1 - x0);
fKx[0] = z0 * (y2 - y1);
fKx[1] = z1 * (y0 - y2);
fKx[2] = z2 * (y1 - y0);
// Note: this could be done with the CrossProduct macro if everything were in a vector
fKz[0] = fKx[0] * x1 - y1 * fKy[0];
fKz[1] = fKx[1] * x2 - y2 * fKy[1];
fKz[2] = fKx[2] * x0 - y0 * fKy[2];
// Calculate the height for each vertex
for (int i = 0; i < nVerts; i++) {
float fScaleX = pVerts[i].xyz[0] * (fKx[0] + fKx[1] + fKx[2]);
float fScaleY = pVerts[i].xyz[1] * (fKy[0] + fKy[1] + fKy[2]);
float fConstZ = fKz[0] + fKz[1] + fKz[2];
// Write back the calculated height into the vertex
pVerts[i].xyz[2] = fScaleY - fScaleX - fConstZ;
}
return qtrue;
assert(
!pPatch->drawinfo.iTriHead
&& va(
"R_TerrainHeightForPoly: point(%f %f) not in patch(%f %f %f)\n",
x,
y,
pPatch->x0,
pPatch->y0,
pPatch->z0
)
);
return qfalse;
}
void R_TerrainRestart_f(void)