Check for the GLX_ARB_fbconfig_float and GLX_NV_float_buffer extensions
to determine if color bufs are floating point.
Check for the GLX_EXT_framebuffer_sRGB extension to determine if the
framebuffer is sRGB capable.
Increase field size for some attribs (visual ID and buffer size) to
accomodate today's larger values.
Also print missing caveats info in verbose mode.
This extension adds a new function which provides an alternative to
eglSwapBuffers. eglSwapBuffersRegionNOK accepts two new parameters in
addition to those in eglSwapBuffers. The new parameters consist of a
pointer to a list of 4-integer blocks defining rectangles (x, y,
width, height) and an integer specifying the number of rectangles in
the list.
When there is no user driver or any matching display drivers we fall
back to the default driver. This patch lets us have a list of default
drivers instead of just one. The drivers are loaded in turn and we
attempt to initialize the display. If it fails we unload the driver
and move on to the next one.
Compared to the display driver mechanism, this avoids loading a number
of drivers and then only using one. Also, we call Initialize to see
if the driver will work instead of relying on Probe. To know for sure
that a driver will work, Probe really have to do a full Initialize, so
we will just use Initialize directly.
This is similar to the GL_QUAD_STRIP -> TRIANGLE_STRIP optimization --
the GS usage to split the quads into tris is a huge bottleneck, so a
quick check improves glean blendFunc time massively (width * height of
the window of single-pixel GL_QUADS, many many times). This may also
end up helping with cairo performance, which sometimes ends up drawing
a single quad.
It produces exactly the same machine code, but it cuts 5% of the
number of instructions generated for a typical shader.
Also, preserve the scalar when length is 1.
