System: Windows 10, SDL2-devel-2.0.9-VC.zip
i would like to report a regression. i am repeatedly rendering an image to a SDL window using an hardware accelerated renderer and vsync enabled.
renderer = SDL_CreateRenderer(window, -1, SDL_RENDERER_ACCELERATED | SDL_RENDERER_PRESENTVSYNC);
if i precisely measure the duration timings using high_resolution_clock::now(), i mostly get exactly the right duration of 16.666 ms, but strangely every three seconds aka 180 frames there is a small drop in performance:
frame drop after 180 dt=0.0302229
frame drop after 180 dt=0.030091
frame drop after 180 dt=0.0300536
the strange thing is: the more webcams ( i have two webcams) i attach to my computer, the longer dt gets.
There must be a problem with SDL_PollEvent (that i call every frame.)
If i call SDL_PollEvent only every 250 frames, i then get a more pronounced frame drop:
frame drop after 250 dt=0.164816
frame drop after 250 dt=0.166964
now, if i switch back to the 2.0.8 release, the problem is non-existing anymore ! so something went wrong somewhere with the latest release.