Meshphong BufferGeometry showing irregular triangles on the surface

I am working on a project that involves a MeshPhong material on a BufferGeometry created using THREE.VertexColors. For some reason I get mesh surface that is not smooth with triangles showing irregular lighting. I checked the normals in the process for creating the mesh and they seem to be fine. Any reason for this occurrence ?

Try using BufferGeometry.computeVertexNormals. The normals may be fine - but they also have to be averaged, otherwise faces are rendered with quite flat shading.


Here is the result of using .computeVertexNormals(). The triangle issue is fixed but it creates a new one! A very pronounced set of longitudinal lines along the geometry.

@prisoner849 @Mugen87 @GlifTek Any idea on how this might be fixed ? :slight_smile:

Would be cool to see how it’s created.

Perhaps try BufferGeometryUtils.mergeVertices( geometry ) before computing vertex normals. A demo would help as we are just guessing here. :slight_smile: