How can Per-Vertex Normal Smoothing Eliminate Faceted Bump Mapping Issues?

Achieving Seamless Tangent Space Normals: A Solution

In an attempt to add bump mapping functionality, you've encountered an issue with faceted models caused by per-face calculations of tangent, binormal, and normal vectors, neglecting the original normals provided in the model file.

Solution: Per-Vertex Normal Smoothing

To resolve this issue, the provided solution proposes a per-vertex normal smoothing technique. Here's the step-by-step process:

1. Per-Vertex Initialization: Begin by initializing an array N[3] to store the normal vector and an integer cnt to zero for each vertex.
2. Per-Vertex Normal Accumulation: For each face, calculate the per-face normal vector. Ensure that it is normalized to unit length. Add this normal vector to all vertices involved in the face and increment cnt by one for each vertex.
3. Per-Vertex Normalization: After processing all faces, for each vertex, divide its accumulated normal vector N by cnt to obtain the average normal from neighboring faces. This step effectively smooths out the normal across all the faces that share the vertex.
4. Tangent and Binormal Calculation: Utilize the smoothed per-vertex normal vectors to compute the tangent and binormal vectors using the existing method. This ensures that the new tangent and binormal vectors are aligned with the smoothed normal.
5. Output: The smoothed normal, tangent, and binormal vectors can now be used to construct the TBN matrix for each vertex, which is essential for accurate bump mapping. This approach results in smooth and seamless bump mapping on the model's surface.

The above is the detailed content of How can Per-Vertex Normal Smoothing Eliminate Faceted Bump Mapping Issues?. For more information, please follow other related articles on the PHP Chinese website!