On 05/12/2017 06:39 AM, John Brooks wrote: > Since release, Dying Light and Dead Island Definitive Edition have been broken > on Mesa, producing at best only a black screen after loading. I found that the > root of the problem is that their vertex shaders redeclare the GLSL builtin > gl_VertexID, which Mesa's compiler considers to be an error: > > error: `gl_VertexID' redeclared
Sorry for not responding to this sooner. I've been away for the last few weeks. I believe that we enforce this as the result of a conformance test that does almost exactly this thing. We didn't used to enforce it, but after discussion with Khronos (which I can dig up), we began enforcing it. This also led to a clarification in the GLSL spec. Section 3.7 (Identifiers) of the GLSL 4.50 spec says: However, as noted in the specification, there are some cases where previously declared variables can be redeclared, and predeclared "gl_" names are allowed to be redeclared in a shader only for these specific purposes. More generally, it is a compile-time error to redeclare a variable, including those starting “gl_”. Redeclaring gl_VertexID is clearly a bug in the game. Has anyone reported this to them? _______________________________________________ mesa-dev mailing list mesa-dev@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/mesa-dev
