unity shadow

这东西好难找LIGHT_ATTENUATION(a) 

shadow 的结果就在这个衰减里，这谁能猜的着，我一点点测出来的，reference也很难找

感谢这位http://blog.csdn.net/candycat1992/article/details/42460959

 

#ifdef POINT
#define LIGHTING_COORDS(idx1,idx2) float3 _LightCoord : TEXCOORD##idx1; SHADOW_COORDS(idx2)
uniform sampler2D _LightTexture0;
uniform float4x4 _LightMatrix0;
#define TRANSFER_VERTEX_TO_FRAGMENT(a) a._LightCoord = mul(_LightMatrix0, mul(_Object2World, v.vertex)).xyz; TRANSFER_SHADOW(a)
#define LIGHT_ATTENUATION(a)    (tex2D(_LightTexture0, dot(a._LightCoord,a._LightCoord).rr).UNITY_ATTEN_CHANNEL * SHADOW_ATTENUATION(a))
#endif

#ifdef DIRECTIONAL
    #define LIGHTING_COORDS(idx1,idx2) SHADOW_COORDS(idx1)
    #define TRANSFER_VERTEX_TO_FRAGMENT(a) TRANSFER_SHADOW(a)
    #define LIGHT_ATTENUATION(a)    SHADOW_ATTENUATION(a)
#endif