The defines a shader reading the depth with getLinearScreenDepth needs. Shared by the effects, so copy them rather than change them.
getLinearScreenDepth
A key identifying those defines, to add to the unique name of such a shader, so that differently stored depths do not share a compiled shader.
The texture the depth is rendered to, the size of the scene - for sizing render targets.
The defines a shader reading the depth with
getLinearScreenDepthneeds. Shared by the effects, so copy them rather than change them.