<html> <head> <base href="https://bugs.freedesktop.org/"> </head> <body> <div> <a class="bz_bug_link bz_status_NEW " title="NEW - No pixel formats with WGL_SWAP_UNDEFINED_ARB && WGL_DOUBLE_BUFFER_ARB=true" href="https://bugs.freedesktop.org/show_bug.cgi?id=100668#c2">Comment # 2</a> on <a class="bz_bug_link bz_status_NEW " title="NEW - No pixel formats with WGL_SWAP_UNDEFINED_ARB && WGL_DOUBLE_BUFFER_ARB=true" href="https://bugs.freedesktop.org/show_bug.cgi?id=100668">bug 100668</a> from <a class="email" href="mailto:brianp@vmware.com" title="Brian Paul <brianp@vmware.com>"> Brian Paul</a> <pre>Hi Charles, I compiled your test program and ran it with Mesa in a Windows VM and wglChoosePixelFormatARB failed to find a pixel format. But I found the exact same failure when I ran it with NVIDIA's OpenGL driver on a Windows 7 system. I also used the wglinfo utility to examine the double buffered pixel formats offered with NVIDIA's driver. None of them use WGL_SWAP_UNDEFINED_ARB. They're all tagged with either WGL_SWAP_EXCHANGE_ARB or WGL_SWAP_COPY_ARB. I would expect that ANGLE is tested with NVIDIA's OpenGL driver, but I don't know how things could work with the ANGLE code I see. When you specify WGL_SWAP_METHOD_ARB = WGL_SWAP_UNDEFINED_ARB you're asking for a very specific type of implementation of wglSwapBuffers(). Any given Windows OpenGL driver is free to implement any of the three swap methods. AFAIK, none are required. Note that WGL_SWAP_UNDEFINED_ARB doesn't mean "don't care". Does ANGLE really require this specific type of buffer swap behavior? If not, the WGL_SWAP_METHOD_ARB attribute should simply be omitted.</pre> </div> <hr> You are receiving this mail because: <ul> <li>You are the QA Contact for the bug.</li> <li>You are the assignee for the bug.</li> </ul> </body> </html>