Add existing to tracked

2026-08-11 09:53:42 -04:00
parent afe07f3055
commit ffd6e3d73c
8531 changed files with 4396230 additions and 0 deletions
@@ -0,0 +1,80 @@
+// See IntersectionUtils.glsl for the definitions of Ray, Intersections, INF_HIT,
+// NO_HIT, setShapeIntersection
+
+/* Clipping plane defines (set in Scene/VoxelRenderResources.js)
+#define CLIPPING_PLANES_UNION
+#define CLIPPING_PLANES_COUNT
+#define CLIPPING_PLANES_INTERSECTION_INDEX
+*/
+
+uniform sampler2D u_clippingPlanesTexture;
+uniform mat4 u_clippingPlanesMatrix;
+
+// Plane is in Hessian Normal Form
+vec4 intersectPlane(in Ray ray, in vec4 plane) {
+    vec3 n = plane.xyz; // normal
+    float w = plane.w; // -dot(pointOnPlane, normal)
+
+    float a = dot(ray.pos, n);
+    float b = dot(ray.dir, n);
+    float t = -(w + a) / b;
+
+    return vec4(n, t);
+}
+
+#ifdef CLIPPING_PLANES
+void intersectClippingPlanes(in Ray ray, inout Intersections ix) {
+    vec4 backSide = vec4(-ray.dir, -INF_HIT);
+    vec4 farSide = vec4(ray.dir, +INF_HIT);
+    RayShapeIntersection clippingVolume;
+
+    #if (CLIPPING_PLANES_COUNT == 1)
+        // Union and intersection are the same when there's one clipping plane, and the code
+        // is more simplified.
+        vec4 planeUv = getClippingPlane(u_clippingPlanesTexture, 0);
+        vec4 intersection = intersectPlane(ray, planeUv);
+        bool reflects = dot(ray.dir, intersection.xyz) < 0.0;
+        clippingVolume.entry = reflects ? backSide : intersection;
+        clippingVolume.exit = reflects ? intersection : farSide;
+        setShapeIntersection(ix, CLIPPING_PLANES_INTERSECTION_INDEX, clippingVolume);
+    #elif defined(CLIPPING_PLANES_UNION)
+        vec4 firstTransmission = vec4(ray.dir, +INF_HIT);
+        vec4 lastReflection = vec4(-ray.dir, -INF_HIT);
+        for (int i = 0; i < CLIPPING_PLANES_COUNT; i++) {
+            vec4 planeUv = getClippingPlane(u_clippingPlanesTexture, i);
+            vec4 intersection = intersectPlane(ray, planeUv);
+            if (dot(ray.dir, planeUv.xyz) > 0.0) {
+                firstTransmission = intersection.w <= firstTransmission.w ? intersection : firstTransmission;
+            } else {
+                lastReflection = intersection.w >= lastReflection.w ? intersection : lastReflection;
+            }
+        }
+        clippingVolume.entry = backSide;
+        clippingVolume.exit = lastReflection;
+        setShapeIntersection(ix, CLIPPING_PLANES_INTERSECTION_INDEX + 0, clippingVolume);
+        clippingVolume.entry = firstTransmission;
+        clippingVolume.exit = farSide;
+        setShapeIntersection(ix, CLIPPING_PLANES_INTERSECTION_INDEX + 1, clippingVolume);
+    #else // intersection
+        vec4 lastTransmission = vec4(ray.dir, -INF_HIT);
+        vec4 firstReflection = vec4(-ray.dir, +INF_HIT);
+        for (int i = 0; i < CLIPPING_PLANES_COUNT; i++) {
+            vec4 planeUv = getClippingPlane(u_clippingPlanesTexture, i);
+            vec4 intersection = intersectPlane(ray, planeUv);
+            if (dot(ray.dir, planeUv.xyz) > 0.0) {
+                lastTransmission = intersection.w > lastTransmission.w ? intersection : lastTransmission;
+            } else {
+                firstReflection = intersection.w < firstReflection.w ? intersection: firstReflection;
+            }
+        }
+        if (lastTransmission.w < firstReflection.w) {
+            clippingVolume.entry = lastTransmission;
+            clippingVolume.exit = firstReflection;
+        } else {
+            clippingVolume.entry = vec4(-ray.dir, NO_HIT);
+            clippingVolume.exit = vec4(ray.dir, NO_HIT);
+        }
+        setShapeIntersection(ix, CLIPPING_PLANES_INTERSECTION_INDEX, clippingVolume);
+    #endif
+}
+#endif