<html> <head> <base href="https://bugs.freedesktop.org/"> </head> <body> <div> <a class="bz_bug_link bz_status_NEW " title="NEW - [radeonsi/Navi] The Bard's Tale IV causes a GPU hang" href="https://bugs.freedesktop.org/show_bug.cgi?id=111591#c16">Comment # 16</a> on <a class="bz_bug_link bz_status_NEW " title="NEW - [radeonsi/Navi] The Bard's Tale IV causes a GPU hang" href="https://bugs.freedesktop.org/show_bug.cgi?id=111591">bug 111591</a> from <a class="email" href="mailto:vgglvyww36@khasekhemwy.net" title="vggl <vgglvyww36@khasekhemwy.net>"> vggl</a> <pre> "The games shaders use GLSL 4.30 which mean interpolation qualifiers must match across shader interfaces otherwise it is a link-time error. In GLSL 4.40 this restriction was relaxed." I believe that relaxation came in version 4.30, not 4.40. The 4.30 spec here: <a href="https://www.khronos.org/registry/OpenGL/specs/gl/GLSLangSpec.4.30.pdf">https://www.khronos.org/registry/OpenGL/specs/gl/GLSLangSpec.4.30.pdf</a> >From the "4.3.4 Input Variables" section: "The fragment shader inputs form an interface with the last active shader in the vertex processing pipeline. For this interface, the last active shader stage output variables and fragment shader input variables of the same name must match in type and qualification, with a few exceptions: The storage qualifiers must, of course, differ (one is in and one is out). Also, interpolation qualification (e.g., flat) and auxiliary qualification (e.g. centroid) may differ. These mismatches are allowed between any pair of stages. When interpolation or auxiliary qualifiers do not match, those provided in the fragment shader supersede those provided in previous stages. If any such qualifiers are completely missing in the fragment shaders, then the default is used, rather than any qualifiers that may have been declared in previous stages. That is, what matters is what is declared in the fragment shaders, not what is declared in shaders in previous stages." That language is identical between 4.30 and 4.40. It sounds like it explicitly allows interpolation qualifiers to differ. However the 4.20 spec language in that section was quite different and did require an interpolation qualifier match. Also, from <a href="https://www.khronos.org/opengl/wiki/Shader_Compilation#Interface_matching">https://www.khronos.org/opengl/wiki/Shader_Compilation#Interface_matching</a>: "If GLSL 4.30 or later is available, then the interpolation qualifiers (including centroid and sample) do not need to match."</pre> </div> <hr> You are receiving this mail because: <ul> <li>You are the assignee for the bug.</li> </ul> </body> </html>