On Wed, 2016-03-30 at 12:48 +0100, Emil Velikov wrote: > Similar to patch 5 - we assume that things will be fine if the base > implementation lacks the WGL extensions. As this can cause the > occasional wtf moment - wouldn't it be better to have a big fat > warning for each of these (three so far) missing extensions alongside > the proposed behaviour ?
Excluding make_current_read I don't think it can make much difference. To trigger a failure mode here you'd need an application that already works _without_ pbuffers or multisampling, that optionally supports them, but that will fail fatally if the extension string is found but not a matching fbconfig (instead of just falling back to the mode in which it already works). Apps are dumb, but I've yet to find one _that_ dumb. > Jon, any ideas how (un)common it is for WGL_ARB_make_current_read, > WGL_ARB_pbuffer and/or WGL_ARB_multisample to be missing ? I had this exact question! Some kind soul on #dri-devel (I forget who, but thank you) pointed me to: http://opengl.gpuinfo.org/gl_extensions.php It's not the best search interface, but we can draw some conclusions anyway. To a first approximation, all WGL implementations supply WGL_ARB_extensions_string (as otherwise you can't query for extensions at all); 1036 reports in that db support it, and 201 do not. Of those 201, there are two that are WGL (and not GLES) implementations anyway: the GDI Generic implementation included with Windows (which isn't accelerated, so we wouldn't get here anyway) and VirtualBox's chromium- based driver. The same set is the set of drivers not supporting WGL_ARB_pbuffer. WGL_ARB_make_current_read is unsupported by 207 reports. Beyond the above, the affected drivers are: vmware with what looks to be llvmpipe (for shame!), Intel GMA5/600, PowerVR SGX545, Matrox M-series, and XGI Volari. WGL_ARB_multisample is unsupported by 252 reports. Beyond the non- pbuffer set this seems to be true of R200-era radeons, geforce 4 and below, and pretty much any Intel chip in compatibility contexts. - ajax _______________________________________________ [email protected]: X.Org development Archives: http://lists.x.org/archives/xorg-devel Info: https://lists.x.org/mailman/listinfo/xorg-devel
