Native bindings to the EXT_disjoint_timer_query extension.

Applications can benefit from accurate timing information in a number of different ways. During application development, timing information can help identify application or driver bottlenecks. At run time, applications can use timing information to dynamically adjust the amount of detail in a scene to achieve constant frame rates. OpenGL implementations have historically provided little to no useful timing information. Applications can get some idea of timing by reading timers on the CPU, but these timers are not synchronized with the graphics rendering pipeline. Reading a CPU timer does not guarantee the completion of a potentially large amount of graphics work accumulated before the timer is read, and will thus produce wildly inaccurate results. glFinish() can be used to determine when previous rendering commands have been completed, but will idle the graphics pipeline and adversely affect application performance.

This extension provides a query mechanism that can be used to determine the amount of time it takes to fully complete a set of GL commands, and without stalling the rendering pipeline. It uses the query object mechanisms first introduced in the occlusion query extension, which allow time intervals to be polled asynchronously by the application.

Requires GLES 2.0.