Cesium反射

反射公式

reflect
//i是入射光线，n是归一化的法线

float3 reflect( float3 i, float3 n )
{
    
  return i - 2.0 * n * dot(n,i);
} 

Cesium实现

reflect(direction, normal) {
    
      var n = Cesium.Cartesian3.dot(normal, direction);
      var t = Cesium.Cartesian3.multiplyByScalar(normal, 2 * n, new Cesium.Cartesian3);
      return Cesium.Cartesian3.subtract(direction, t, new Cesium.Cartesian3);
}