GL specs are generally quite accurate, now that there are real conformance tests for implementations. They can feel imprecise though, as they tend to leave a b

GL specs are generally quite accurate, now that there are real conformance tests for implementations. They can feel imprecise though, as they tend to leave a bunch more as undefined, whereas d3d tends to be more strict, leaving fewer choices to implementations. Of course, the D3D11 spec didn't used to be public at all.