diff options
| author | ladevieq <ladevie.quentin@gmail.com> | 2021-09-26 23:57:26 +0200 |
|---|---|---|
| committer | ladevieq <ladevie.quentin@gmail.com> | 2021-09-26 23:57:26 +0200 |
| commit | c5119193ffaedf4ac94fecfb434a3292a4746259 (patch) | |
| tree | 398031c5d1e920fec21e53feacd1d55ba8a79dad /shaders/include/ray.h | |
| parent | bbba71cfe5a9545f1a87c70eb3cab3b6b08b1b25 (diff) | |
Refactor gltf loading and triangles attributes
Diffstat (limited to 'shaders/include/ray.h')
| -rw-r--r-- | shaders/include/ray.h | 155 |
1 files changed, 155 insertions, 0 deletions
diff --git a/shaders/include/ray.h b/shaders/include/ray.h new file mode 100644 index 0000000..38e5c16 --- /dev/null +++ b/shaders/include/ray.h @@ -0,0 +1,155 @@ +struct ray {
+ vec3 origin;
+ vec3 direction;
+ float min_t;
+ float max_t;
+};
+
+vec3 at(ray r, float t) {
+ return r.origin + r.direction * t;
+}
+
+struct hit_info {
+ vec3 point;
+ vec3 barycentrics;
+ vec3 geometry_normal;
+ vec3 shading_normal;
+ vec3 color;
+ vec2 metalness_roughness;
+ vec2 uv;
+ float t;
+ uint id;
+};
+
+bool hit_aabb(vec3 minimum, vec3 maximum, ray r) {
+ const vec3 invdir = 1.0 / r.direction;
+ const vec3 f = (maximum.xyz - r.origin.xyz) * invdir;
+ const vec3 n = (minimum.xyz - r.origin.xyz) * invdir;
+
+ const vec3 tmax = max(f, n);
+ const vec3 tmin = min(f, n);
+
+ const float t1 = min(min(tmax.x, min(tmax.y, tmax.z)), r.max_t);
+ const float t0 = max(max(max(tmin.x, max(tmin.y, tmin.z)), r.min_t), 0.0f);
+
+ return t1 >= t0;
+}
+
+uint hit_aabbs(ray r) {
+ uint hit_count = 0;
+ int id = 0;
+
+ while(id != -1) {
+ if (bufs.bvh.nodes[id].primitive_id != -1) {
+ // triangle tri = bufs.geometry.triangles[bufs.bvh.nodes[id].primitive_id];
+ // vec3 minimum = min(tri.v1.position, min(tri.v2.position, tri.v3.position)).xyz;
+ // vec3 maximum = max(tri.v1.position, max(tri.v2.position, tri.v3.position)).xyz;
+
+ // if (hit_aabb(minimum, maximum, r)) {
+ // hit_count++;
+ // }
+ id = bufs.bvh.nodes[id].next_id;
+ } else if (hit_aabb(bufs.bvh.nodes[id].min, bufs.bvh.nodes[id].max, r)) {
+ hit_count++;
+ id++;
+ } else {
+ id = bufs.bvh.nodes[id].next_id;
+ }
+ }
+
+ return hit_count;
+}
+
+bool hit_sphere(sphere s, ray r, out hit_info info) {
+ vec3 origin_center = r.origin - s.position.xyz;
+
+ float a = dot(r.direction, r.direction);
+ float half_b = dot(r.direction, origin_center);
+ float c = dot(origin_center, origin_center) - s.radius * s.radius;
+ float discriminant = half_b * half_b - a * c;
+
+ if (discriminant < 0) {
+ return false;
+ }
+
+ float sqrt_discriminant = sqrt(discriminant);
+ float root = (-half_b - sqrt_discriminant) / a;
+ if (root < r.min_t || root > r.max_t) {
+ root = (-half_b + sqrt_discriminant) / a;
+
+ if (root < r.min_t || root > r.max_t) {
+ return false;
+ }
+ }
+
+ info.t = root;
+ // info.point = at(r, info.t);
+
+ // vec3 outward_normal = (info.point - s.position.xyz) / s.radius;
+ // bool front_face = dot(outward_normal, r.direction) < 0.0;
+ // info.normal = front_face ? outward_normal : -outward_normal;
+
+ return true;
+}
+
+bool hit_triangle(uint id, ray r, out hit_info info) {
+ uint id1 = bufs.indices_arr.indices[id * 3] & 0x00ffffff;
+ uint id2 = bufs.indices_arr.indices[id * 3 + 1] & 0x00ffffff;
+ uint id3 = bufs.indices_arr.indices[id * 3 + 2] & 0x00ffffff;
+
+ vec3 p1 = vec3(bufs.positions_arr.positions[id1 * 3], bufs.positions_arr.positions[id1 * 3 + 1], bufs.positions_arr.positions[id1 * 3 + 2]);
+ vec3 p2 = vec3(bufs.positions_arr.positions[id2 * 3], bufs.positions_arr.positions[id2 * 3 + 1], bufs.positions_arr.positions[id2 * 3 + 2]);
+ vec3 p3 = vec3(bufs.positions_arr.positions[id3 * 3], bufs.positions_arr.positions[id3 * 3 + 1], bufs.positions_arr.positions[id3 * 3 + 2]);
+
+ vec3 v2v1 = p2 - p1;
+ vec3 v3v1 = p3 - p1;
+
+ vec3 originv1 = r.origin - p1;
+ vec3 normal = cross(v2v1, v3v1);
+ vec3 q = cross(originv1, r.direction);
+ float d = 1.0 / dot(r.direction, normal);
+ float u = d * dot(-q, v3v1);
+ float v = d * dot(q, v2v1);
+ float t = d * dot(-normal, originv1);
+
+ if (u < 0.0 || u > 1.0 || v < 0.0 || u + v > 1.0 || t < r.min_t || t > r.max_t) {
+ return false;
+ }
+
+ info.t = t;
+ info.barycentrics = vec3(1 - u - v, u, v);
+ info.geometry_normal = normalize(normal);
+ info.id = id;
+
+ return true;
+}
+
+bool hit_node(ray r, out hit_info info) {
+ hit_info temp_info;
+ bool hit = false;
+ int id = 0;
+
+ while(id != -1) {
+ // Leafs
+ if (bufs.bvh.nodes[id].primitive_id != -1) {
+ // if (hit_sphere(bufs.geometry.spheres[bufs.bvh.nodes[id].primitive_id], r, temp_info)) {
+ // info = temp_info;
+ // r.max_t = temp_info.t;
+ // hit = true;
+ // }
+ if (hit_triangle(bufs.bvh.nodes[id].primitive_id, r, temp_info)) {
+ info = temp_info;
+ r.max_t = temp_info.t;
+ hit = true;
+ }
+ id = bufs.bvh.nodes[id].next_id;
+ } else if (hit_aabb(bufs.bvh.nodes[id].min, bufs.bvh.nodes[id].max, r)) {
+ id++;
+ } else {
+ id = bufs.bvh.nodes[id].next_id;
+ }
+ }
+
+ info.point = at(r, info.t);
+ return hit;
+}
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