rlm@4: package com.aurellem.capture;
rlm@4: 
rlm@4: import com.jme3.system.Timer;
rlm@4: 
rlm@54: /**
rlm@54:  * A standard JME3 application that extends SimpleApplication or
rlm@54:  * Application tries as hard as it can to keep in sync with
rlm@54:  * user-time. If a ball is rolling at 1 game-mile per game-hour in the
rlm@54:  * game, and you wait for one user-hour as measured by the clock on
rlm@54:  * your wall, then the ball should have traveled exactly one
rlm@54:  * game-mile. In order to keep sync with the real world, the game
rlm@54:  * throttles its physics engine and graphics display. If the
rlm@54:  * computations involved in running the game are too intense, then the
rlm@54:  * game will first skip frames, then sacrifice physics accuracy. If
rlm@54:  * there are particularly demanding computations, then you may only get
rlm@54:  * 1 fps, and the ball may tunnel through the floor or obstacles due
rlm@54:  * to inaccurate physics simulation, but after the end of one
rlm@54:  * user-hour, that ball will have traveled one game-mile.
rlm@54:  *
rlm@54:  * When we're recording video or audio, we don't care if the game-time
rlm@54:  * syncs with user-time, but instead whether the time in the recorded
rlm@54:  * video (video-time) syncs with user-time. To continue the analogy,
rlm@54:  * if we recorded the ball rolling at 1 game-mile per game-hour and
rlm@54:  * watched the video later, we would want to see 30 fps video of the
rlm@54:  * ball rolling at 1 video-mile per user-hour. It doesn't matter how
rlm@54:  * much user-time it took to simulate that hour of game-time to make
rlm@54:  * the high-quality recording.  If an Application uses this IsoTimer
rlm@54:  * instead of the normal one, we can be sure that every call to
rlm@54:  * simpleUpdate, for example, corresponds to exactly (1 / fps) seconds
rlm@54:  * of game-time. This let's us record perfect video and audio even on
rlm@54:  * a slow computer.
rlm@54:  *
rlm@54:  * @author Robert McIntyre
rlm@54:  *
rlm@54:  */
rlm@54: 
rlm@4: public class IsoTimer extends Timer {
rlm@4: 
rlm@4: 	private float framerate;
rlm@4: 	private int ticks;
rlm@4: 	
rlm@4: 	public IsoTimer(float framerate){
rlm@4: 		this.framerate = framerate;
rlm@54: 		this.ticks = 0;
rlm@54: 	}
rlm@4: 	
rlm@4: 	public long getTime() {
rlm@54: 		return (long) (this.ticks / this.framerate);
rlm@54: 	}
rlm@4: 	
rlm@4: 	public long getResolution() {
rlm@54: 		return 1000000000L;
rlm@54: 	}
rlm@4: 	
rlm@4: 	public float getFrameRate() {
rlm@54: 		return this.framerate;
rlm@54: 	}
rlm@4: 	
rlm@4: 	public float getTimePerFrame() {
rlm@54: 		return (float) (1.0f / this.framerate);
rlm@54: 	}
rlm@4: 
rlm@4: 	public void update() {this.ticks++;}
rlm@4: 	
rlm@4: 	public void reset() {this.ticks = 0;}
rlm@4: 
rlm@4: }