这是一个相对来说比较简单的节点, 他使用物体法线和摄像机射线的夹角来控制透明度, 以达到平滑 的渐隐效果。
This is a relatively simple node that uses the angle between the object normal and the camera ray to control the transparency, achieving a smooth fade effect.
uniform vec3 norm; uniform vec3 cam; void main() { ... float alpha = dot(norm, cam); ... }