Changing Default Resolution of Windows Timer To Increase Graphics Speed

[Eugene_Dakin]

@306844:@Dave S

By default, the clock interrupt and timer tick are the same, but Windows or an application can change the clock interrupt period.

Thanks for the comments Dave. I seem to remember reading how the clock interrupt is related to the Intel chip, which has about a 2.81 GHz speed - thats alot of cycles per second. The NtSetTimerResolution is designed to modify the global timer resolution for media to allow programs to increase their updates for games and video. NtSetTimerResolution can be set to 0.5 milliseconds on my specific machine, instead of the default 15.6 ms.

@306844:@Dave S

plus if your refresh rate exceeds that of the monitor you should not be able to percieve a flicker… for that matter, if your FPS exceeds even 24fps it should be hard to percieve it… since that is the retention period of most peoples eyes (and why movies were shot at that speed (on film)…digital is faster these days)

I like where you are going with this. I have a 1920x1080 monitor, and the refresh rate of the hardware on an Mini Displayport using DVI is 240 frames per second, which is well above the 24 fps. The hardware doesn’t seem to be the issue, and when using a thread can provide very fast frames per second - Here is some of the test data from a previous post: Speed

Computer No Mouse Movement (fps) Mouse Movement (fps) Surface Book (VGA) 1700-1900 2500-2800 Mac Mini (Late 2009) 50-61 56-61 Mac Mini (Late 2012) 60 61 ASUS 1000-2300 3100-3300 Surface Pro I 900-1400 1300-1500

The Windows computer seems to be able to have a high frames per second output, along with the ability to process and render code extremely fast. There seems to be something that I don’t understand with the Timer in Xojo that causes flickering - which is likely below the 24 frames per second that is mentioned. My thought (which may be incorrect) is to lower the refresh rate of the global timer from 15.6 milliseconds (62 fps) to 0.5 milliseconds (2000 fps).

I don’t know the answer, and it doesn’t hurt to ask. Thanks for your thoughts Dave, and it seems like there might be something else in the background of Xojo with the timer that I am not aware.