I cannot access the upgrade guide found in this post , don’t have permission.
Click request access I guess…
Sorry people, our upgrade guide is not yet available. I will update the post when I get the official link.
In the meantime, this is mostly what you need to know about when updating to 2017.3:
PassType.VertexLMRGBM has been deprecated
Starting with Unity 2017.3, the shader pass “VertexLMRGBM” (e.g. Tags { “LightMode” = “VertexLMRGBM” }) will be ignored. Instead, the user has to provide or update a “VertexLM” shader pass using DecodeLightmap shader function that supports all types of lightmap encodings.
Built-in mobile shaders have been upgraded and they use DecodeLightmap shader function now. In the case of old projects that used built-in mobile shaders(e.g. Mobile/VertexLit) on Desktop platforms, the lighting output might change because the maximum range of RGBM encoded values was [0, 8] and now it’s [0, 5].