gl_video_resize_redraw() simply resizes and redraws (but without
invoking swapGlBuffers()). The VO is not involved in any way, so this
can simply be called from inside the mpgl lock from any thread.
Requires a minor refactor of the GL OSD code in order to redraw without
an OSD object.
Allows playing video with alpha information on X11, as long as the video
contains alpha and the window manager does compositing. See vo.rst.
Whether a window can be transparent is decided by the choice of the X
Visual used for window creation. Unfortunately, there's no direct way to
request such a Visual through the GLX or the X API, and use of the
XRender extension is required to find out whether a Visual implies a
framebuffer with alpha used by XRender (see for example [1]). Instead of
depending on the XRender wrapper library (which would require annoying
configure checks, even though XRender is virtually always supported),
use a simple heuristics to find out whether a Visual has alpha. Since
getting it wrong just means an optional feature will not work as
expected, we consider this ok.
[1] http://stackoverflow.com/questions/4052940/how-to-make-an-opengl-rendering-context-with-transparent-background/9215724#9215724
gl_video.c contains all rendering code, gl_lcms.c the .icc loader and
creation of 3D LUT (and all LittleCMS specific code). vo_opengl.c is
reduced to interfacing between the various parts.
wm4