From 20c92e9afd374132268028e709688dc286f9d7df Mon Sep 17 00:00:00 2001
From: Lucas Dower <lucasjdower@gmail.com>
Date: Sat, 14 May 2022 20:22:38 +0100
Subject: [PATCH] Improved handling of malformed meshes

---
 src/voxelisers/base-voxeliser.ts    | 8 ++++++--
 src/voxelisers/bvh-ray-voxeliser.ts | 5 ++++-
 2 files changed, 10 insertions(+), 3 deletions(-)

diff --git a/src/voxelisers/base-voxeliser.ts b/src/voxelisers/base-voxeliser.ts
index c7826e8..c82c366 100644
--- a/src/voxelisers/base-voxeliser.ts
+++ b/src/voxelisers/base-voxeliser.ts
@@ -1,5 +1,5 @@
 import { UVTriangle, Triangle } from '../triangle';
-import { RGB, UV } from '../util';
+import { ASSERT, RGB, UV } from '../util';
 import { Vector3 } from '../vector';
 import { Mesh } from '../mesh';
 import { VoxelMesh, VoxelMeshParams} from '../voxel_mesh';
@@ -20,7 +20,7 @@ export abstract class IVoxeliser {
 
     protected abstract _voxelise(mesh: Mesh, voxelMeshParams: VoxelMeshParams): VoxelMesh;
 
-    protected _getVoxelColour(mesh: Mesh, triangle: UVTriangle, materialName: string, location: Vector3, filtering: TextureFiltering): RGB {
+    protected _getVoxelColour(mesh: Mesh, triangle: UVTriangle, materialName: string, location: Vector3, filtering: TextureFiltering): (RGB | undefined) {
         const area01 = new Triangle(triangle.v0, triangle.v1, location).getArea();
         const area12 = new Triangle(triangle.v1, triangle.v2, location).getArea();
         const area20 = new Triangle(triangle.v2, triangle.v0, location).getArea();
@@ -35,6 +35,10 @@ export abstract class IVoxeliser {
             triangle.uv0.v * w0 + triangle.uv1.v * w1 + triangle.uv2.v * w2,
         );
         
+        if (isNaN(uv.u) || isNaN(uv.v)) {
+            return undefined;
+        }
+        
         return mesh.sampleMaterial(materialName, uv, filtering);
     }
 }
diff --git a/src/voxelisers/bvh-ray-voxeliser.ts b/src/voxelisers/bvh-ray-voxeliser.ts
index cf16927..9d3b7ce 100644
--- a/src/voxelisers/bvh-ray-voxeliser.ts
+++ b/src/voxelisers/bvh-ray-voxeliser.ts
@@ -90,7 +90,10 @@ export class BVHRayVoxeliser extends IVoxeliser {
                     position,
                     voxelMeshParams.textureFiltering,
                 );
-                voxelMesh.addVoxel(position, voxelColour);
+
+                if (voxelColour) {
+                    voxelMesh.addVoxel(position, voxelColour);
+                }
             }
         }