2014/10/15 下午 10:04:58

iphone Programming Glossary: cfabsolutetimegetcurrent

Hardware accelerated h.264 decoding to texture, overlay or similar in iOS

http://stackoverflow.com/questions/10646657/hardware-accelerated-h-264-decoding-to-texture-overlay-or-similar-in-ios

CVPixelBufferGetHeight movieFrame int bufferWidth CVPixelBufferGetWidth movieFrame CFAbsoluteTime startTime CFAbsoluteTimeGetCurrent if GPUImageOpenGLESContext supportsFastTextureUpload CVPixelBufferLockBaseAddress movieFrame 0 GPUImageOpenGLESContext..

Is it possible to get the atomic clock timestamp from the iphone GPS?

http://stackoverflow.com/questions/1444456/is-it-possible-to-get-the-atomic-clock-timestamp-from-the-iphone-gps

clock which is accessible via the above method. The CoreFoundation equivalent is something like CFAbsoluteTime now CFAbsoluteTimeGetCurrent Which returns the CoreFoundation equivalent of the normal UNIX seconds since epoch timestamp. share improve this answer..

UILabel updating stops during scrolling UIScrollView

http://stackoverflow.com/questions/5377914/uilabel-updating-stops-during-scrolling-uiscrollview

of scrolling or not. Here is how the label updates are implemented void startElapsedTimeTimer self setStartTime CFAbsoluteTimeGetCurrent NSTimer elapsedTimeTimer NSTimer scheduledTimerWithTimeInterval 0.001 target self selector @selector updateElapsedTimeLabel.. @selector updateElapsedTimeLabel userInfo nil repeats YES void updateElapsedTimeLabel CFTimeInterval currentTime CFAbsoluteTimeGetCurrent float theTime currentTime startTime elapsedTimeLabel.text NSString stringWithFormat @ 1.2f sec. theTime Thanks for any help...

How to measure true FPS performance of OpenGL ES?

http://stackoverflow.com/questions/6586635/how-to-measure-true-fps-performance-of-opengl-es

rendering performance. It's trivial to encapsulate your rendering in something like CFTimeInterval previousTimestamp CFAbsoluteTimeGetCurrent Do your OpenGL ES frame rendering here as well as presenting the onscreen render buffer CFTimeInterval frameDuration CFAbsoluteTimeGetCurrent.. Do your OpenGL ES frame rendering here as well as presenting the onscreen render buffer CFTimeInterval frameDuration CFAbsoluteTimeGetCurrent previousTimestamp NSLog @ Frame duration f ms frameDuration 1000.0 to obtain rendering time. If you want it your instantaneous..