Some of the tests are making direct GL calls. Eventually we want
Clutter not to link directly against any GL library so that it can
leave Cogl to load it dynamically. As a step towards getting this to
work this patch changes the tests to resolve the symbols using
cogl_get_proc_address instead of linking directly.
This greatly speeds up running all the conformance tests by no longer
delaying many of the tests for a number of dummy frames to be painted.
We used to skip frames because we thought there was a problem with the
driver's glReadPixels implementation. Although we have seen driver
issues at times the real reason the delay was needed was because
resizing the stage usually happens asynchronously (because a non
synchronous X request is used by clutter_stage_set_size()). We now force
all X requests to be synchronized for the conformance tests so this is
no longer a problem and we can avoid these hacks.
This test breaks out into raw OpenGL to create a RECTANGLE texture so it
needs to be careful not to trample on any state that may be cached by
Cogl internally.
The test creates a GL_TEXTURE_RECTANGLE_ARB texture using
cogl_texture_new_from_foreign and confirms that rendering it works
correctly. If the rectangle texture extension isn't available then
this test always succeeds.
http://bugzilla.openedhand.com/show_bug.cgi?id=2015
