gui_toolkit 0.34.0

Fixed

• Raising then lowering set_max_frame_latency no longer leaves the swap chain with two frames in flight for good (render/present.odin, render/render.odin, D3D11): the swap chain's frame latency object is a semaphore that the system raises when MaximumFrameLatency goes up and does not take back when it goes down. After a 1 -> 2 -> 1 (an app that allows a second frame for a resize step or an input frame, as Wren does) the object held one count more than a slot per round trip: every wait on frame_waitable returned at once, Present blocked for a whole refresh instead, and the frame on screen was one more frame behind the input, until the program restarted. The surplus is now remembered when the latency is lowered (Present_State.latency_debt) and consumed, without waiting, by frame_waitable / wait_for_frame as soon as the object has the counts to give. Measured on a 60 Hz window (a tab dragged at 1 kHz of pointer moves): wait for the slot 0.1 ms and Present 16 ms before, 16 ms and 0.6 ms after, and the time from input to the refresh that showed it, as the frame statistics give it, from 118 ms to 56 ms.

Added

• render/latency_object_test.odin: the surplus of the latency object against a semaphore that stands for it (lowering, raising, taking without waiting, counts that come later).