https://bugs.winehq.org/show_bug.cgi?id=41930
--- Comment #25 from Bryan Varner bryan@varnernet.com --- Created attachment 66434 --> https://bugs.winehq.org/attachment.cgi?id=66434 osmesa-byte-fix.patch
According to the Mesa docs, only GL_UNSIGNED_BYTE is supported, ever. This is a quick hack to restore the original functionality.