+bool Chunk::Intersection(const Ray &ray, const glm::mat4 &M, int *blkid, float *dist) const {
+ { // rough check
+ const AABB bb{{0, 0, 0}, {Width(), Height(), Depth()}};
+ if (!blank::Intersection(ray, bb, M)) {
+ return false;
+ }
+ }
+
+ if (!blkid && !dist) {
+ return true;
+ }
+
+ // TODO: should be possible to heavily optimize this
+ int id = 0;
+ int closest_id = -1;
+ float closest_dist = std::numeric_limits<float>::infinity();
+ for (int z = 0; z < Depth(); ++z) {
+ for (int y = 0; y < Height(); ++y) {
+ for (int x = 0; x < Width(); ++x, ++id) {
+ if (!blocks[id].type->visible) {
+ continue;
+ }
+ const AABB bb{{x, y, z}, {x+1, y+1, z+1}};
+ float cur_dist;
+ if (blank::Intersection(ray, bb, M, &cur_dist)) {
+ if (cur_dist < closest_dist) {
+ closest_id = id;
+ closest_dist = cur_dist;
+ }
+ }
+ }
+ }
+ }
+
+ if (closest_id < 0) {
+ return false;
+ }
+
+ if (blkid) {
+ *blkid = closest_id;
+ }
+ if (dist) {
+ *dist = closest_dist;
+ }
+ return true;
+}
+
+