[cairo] cairo wgl trouble
Henry (Yu) Song
henry.song at samsung.com
Wed Mar 4 19:26:05 PST 2015
Does anybody try to build cairo with wgl support on windows (windows 8 in my case)?
I have fixed two issues
(1) cairo_wgl_device_create (HGLRC rc) API is not correct. In order to create a compatible dummy DC, one must use the same pixel format used to create rc. A more correct API should be cairo_wgl_device_create (HGLRC rc, int pixel_format)
(2) OpenGL 3.0+ uses glGetStringi (GL_EXTENSIONS, index) to query for extensions. So this must be changed in cairo-gl-info.c - glGetString (GL_EXTENSIONS) returns invalid enum.
I did change these two issues, but more issues ahead.
in cairo-gl-info.c/_cairo_get_gl_flavor (), querying for const char *version = (const char *) glGetString (GL_VERSION) is successful. But after calling strstr (version, "OpenGL ES 2"), this version "auto-magically" changed to point to "OpenGL ES 2" string, and gl_flavor becomes CAIRO_GL_FLAVOR_ES - this is inspected within visual studio 2012. Why?
Thanks in advance
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