void render8(MathTree* tree, Region region,
uint8_t** img, volatile int* halt,
void (*callback)())
{
// Special interrupt system, set asynchronously by on high
if (*halt) return;
// Render pixel-by-pixel if we're below a certain size.
if (region.voxels > 0 && region.voxels < MIN_VOLUME) {
if (callback) (*callback)();
region8(tree, region, img);
return;
}
// Pre-emptively halt evaluation if all the points in this
// region are already light.
uint8_t L = region.L[region.nk] >> 8;
bool cull = true;
for (int row = region.jmin; cull && row < region.jmin + region.nj; ++row) {
for (int col = region.imin; cull && col < region.imin + region.ni; ++col) {
if (L > img[row][col]) {
cull = false;
break;
}
}
}
if (cull) return;
Interval X = {region.X[0], region.X[region.ni]},
Y = {region.Y[0], region.Y[region.nj]},
Z = {region.Z[0], region.Z[region.nk]};
Interval result = eval_i(tree, X, Y, Z);
// If we're inside the object, fill with color.
if (result.upper < 0) {
for (int row = region.jmin; row < region.jmin + region.nj; ++row) {
for (int col = region.imin; col < region.imin + region.ni; ++col) {
if (L > img[row][col]) img[row][col] = L;
}
}
}
// In unambiguous cases, return immediately
if (result.upper < 0 || result.lower >= 0) return;
#if PRUNE
disable_nodes(tree);
disable_nodes_binary(tree);
#endif
// Subdivide and recurse if we're not at voxel size.
if (region.ni*region.nj*region.nk > 1) {
Region A, B;
bisect(region, &A, &B);
render8(tree, B, img, halt, callback);
render8(tree, A, img, halt, callback);
}
#if PRUNE
enable_nodes(tree);
#endif
}
void Mesher::unload_packed()
{
enable_nodes(tree);
has_data = false;
}
