CULLING FINALLY WORKS

res/shaders/MeshletBasePass.slang

@@ -25,8 +25,8 @@ void taskMain(
 	if(threadID == 0)
 	{
 		head = 0;
-		float3 origin = float3(0, 0, 0);
-		const float offset = 600.0f;
+		float3 origin = viewToModel(instance.inverseTransformMatrix, float4(0, 0, 0, 1)).xyz;
+		const float offset = 0.0f;
 		float3 corners[4] = {
 			screenToModel(instance.inverseTransformMatrix, float4(offset, offset, -1.0f, 1.0f)).xyz,
 			screenToModel(instance.inverseTransformMatrix, float4(pViewParams.screenDimensions.x - offset, offset, -1.0f, 1.0f)).xyz,

res/shaders/lib/Bounding.slang

@@ -31,24 +31,24 @@ struct AABB
     float pad0;
 	float3 max;
     float pad1;
+    // modified version from https://learnopengl.com/Guest-Articles/2021/Scene/Frustum-Culling
 	bool insideFrustum(Frustum frustum)
     {
-		float3 corners[8];
-        corners[0] = float3(min.x, min.y, min.z);
-        corners[1] = float3(min.x, min.y, max.z);
-        corners[2] = float3(min.x, max.y, min.z);
-        corners[3] = float3(min.x, max.y, max.z);
-        corners[4] = float3(max.x, min.y, min.z);
-        corners[5] = float3(max.x, min.y, max.z);
-        corners[6] = float3(max.x, max.y, min.z);
-        corners[7] = float3(max.x, max.y, max.z);
-        for(int i = 0; i < 8; ++i)
+        float3 center = (min + max) * 0.5;
+        float3 extents = float3(max.x - center.x, max.y - center.y, max.z - center.z);
+        bool result = true;
+        for(int i = 0; i < 4 && result; ++i)
         {
-            if(frustum.pointInside(corners[i]))
+            const float r = extents.x * abs(frustum.sides[i].n.x) 
+                          + extents.y * abs(frustum.sides[i].n.y) 
+                          + extents.z * abs(frustum.sides[i].n.z);
+
+            const float signedDistance = dot(frustum.sides[i].n, center) - frustum.sides[i].d;
+            if(signedDistance < -r)
             {
-                return true;
+                result = false;
             }
         }
-        return false;
+        return result;
 	}
 };

res/shaders/lib/Common.slang

@@ -31,6 +31,13 @@ float4 viewToWorld(float4 view)
     return world;
 }
 
+float4 viewToModel(float4x4 inverseTransform, float4 view)
+{
+    float4 world = viewToWorld(view);
+
+    return worldToModel(inverseTransform, world);
+}
+
 float4 clipToView(float4 clip)
 {
     float4 view = mul(pViewParams.inverseProjection, clip);

res/shaders/lib/Scene.slang

@@ -2,7 +2,7 @@ import Bounding;
 
 struct MeshletDescription
 {
-	BoundingSphere bounding;
+	AABB bounding;
 	uint32_t vertexCount;
 	uint32_t primitiveCount;
 	uint32_t vertexOffset;
@@ -13,7 +13,7 @@ struct MeshletDescription
 
 struct MeshData
 {
-	BoundingSphere bounding;
+	AABB bounding;
 	uint32_t numMeshlets;
 	uint32_t meshletOffset;
 	uint32_t firstIndex;