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GLX_OML_sync_control broken under Xwayland 1.16.1

Submitted by William Light

Assigned to Wayland bug list

Link to original bug (#85183)

Description

I have some XCB OpenGL code which, in the meantime until I port it to Wayland, I would like to be able to use under Xwayland.

I use the OML_sync_control extension to discover refresh rate (with glXGetMscRateOML()) and I use glXSwapBuffersMscOML() instead of glXSwapBuffers(). Unfortunately, neither of these functions seem to work under XWayland 1.16.1. The Xwayland window shows up black, but when I switch back to glXSwapBuffers(), rendering and display proceeds as expected.

I am also getting garbage results from glXGetMscRateOML(). Under Xorg on this machine, I get a (numerator, denominator) pair of (687500, 11457) (~60.006hz). Under XWayland, I get a variety of numerators and denominators, none of which are close to 60hz. Several samples of the return values I get are (1, 22259776), (1, 11782208), (1, 9910336), and (1, 22751296).

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