Blender节点源码 - Layer Weight

Blender Node Source Code - Layer Weight

Nov 19, 24

这个节点很像Fallout, 也是通过法线和摄像机射线的夹角计算一个用来混合的权重。

This node is similar to Fallout, also calculating a weight for blending using the angle between the normal and the camera ray.

Source Code


void node_layer_weight(float blend, vec3 N, out float fresnel, out float facing) {
  N = normalize(N);

  /* fresnel */
  float eta = max(1.0 - blend, 0.00001);
  vec3 V = coordinate_incoming(g_data.P);

  fresnel = fresnel_dielectric(V, N, (FrontFacing) ? 1.0 / eta : eta);

  /* facing */
  facing = abs(dot(V, N));
  if (blend != 0.5) {
    blend = clamp(blend, 0.0, 0.99999);
    blend = (blend < 0.5) ? 2.0 * blend : 0.5 / (1.0 - blend);
    facing = pow(facing, blend);
  }
  facing = 1.0 - facing;
}