public static void generate(TriMesh mesh) {
FloatBuffer tangents = BufferUtils.createFloatBuffer(mesh.getVertexCount() * 3);
FloatBuffer binormals = BufferUtils.createFloatBuffer(mesh.getVertexCount() * 3);
IntBuffer indexBuffer = mesh.getIndexBuffer();
FloatBuffer vertexBuffer = mesh.getVertexBuffer();
FloatBuffer textureBuffer = mesh.getTextureCoords(0).coords;
indexBuffer.rewind();
Vector3f tangent = new Vector3f();
Vector3f binormal = new Vector3f();
Vector3f normal = new Vector3f();
Vector3f verts[] = new Vector3f[3];
Vector2f texcoords[] = new Vector2f[3];
for (int i = 0; i < 3; i++) {
verts[i] = new Vector3f();
texcoords[i] = new Vector2f();
}
for (int t = 0; t < indexBuffer.capacity() / 3; t++) {
int index[] = new int[3];
for (int v = 0; v < 3; v++) {
index[v] = indexBuffer.get();
verts[v].x = vertexBuffer.get(index[v] * 3);
verts[v].y = vertexBuffer.get(index[v] * 3 + 1);
verts[v].z = vertexBuffer.get(index[v] * 3 + 2);
texcoords[v].x = textureBuffer.get(index[v] * 2);
texcoords[v].y = textureBuffer.get(index[v] * 2 + 1);
}
computeTriangleTangentSpace(tangent, binormal, normal, verts, texcoords);
for (int v = 0; v < 3; v++) {
tangents.position(index[v] * 3);
tangents.put(tangent.x);
tangents.put(tangent.y);
tangents.put(tangent.z);
binormals.position(index[v] * 3);
binormals.put(binormal.x);
binormals.put(binormal.y);
binormals.put(binormal.z);
}
}
mesh.setTangentBuffer(tangents);
mesh.setBinormalBuffer(binormals);
}
