Unity 2018 Shaders and Effects Cookbook - Third Edition

Altering the geometry

The second effect of this shader alters the geometry to simulate the accumulation of snow. Firstly, we identify which triangles have been colored white by testing the same condition used in the surface function. This time, unfortunately, we cannot rely on WorldNormalVector() as the SurfaceOutputStandard structure is not yet initialized in the vertex modifier. We use this other method instead, which converts _SnowDirection to object coordinates:

float4 sn = mul(UNITY_MATRIX_IT_MV, _SnowDirection);

Then, we can extrude the geometry to simulate the accumulation of snow:

if (dot(v.normal, sn.xyz) >= _Snow){    v.vertex.xyz += (sn.xyz + v.normal) * _SnowDepth * _Snow;}

Once again, this is a very basic effect. You could use a ...