From kde-commits  Mon Sep 01 19:24:14 2008
From: Rivo Laks <rivolaks () hot ! ee>
Date: Mon, 01 Sep 2008 19:24:14 +0000
To: kde-commits
Subject: playground/libs/kgllib/core/kgllib
Message-Id: <1220297054.826138.21211.nullmailer () svn ! kde ! org>
X-MARC-Message: https://marc.info/?l=kde-commits&m=122029706532709

SVN commit 855942 by rivol:

Docufy

 M  +65 -0     fpscounter.h  


--- trunk/playground/libs/kgllib/core/kgllib/fpscounter.h #855941:855942
@@ -28,18 +28,83 @@
 namespace KGLLib
 {
 
+/**
+ * @brief Utility class that measures FPS.
+ *
+ * FPSCounter is a utility class that keeps track of FPS (frames per second) of
+ *  your application. It can be a simple performance measurement tool.
+ *
+ * Using FPSCounter is simple: if you're using GLWidget then all you have to do
+ *  is calling fps() or fpsString() method to find out the current FPS. You can
+ *  also call timeElapsed() to find out how much time has elapsed since last
+ *  frame was rendered. This could be useful e.g. in animations where an object
+ *  has a fixed speed and you multiply it by the elapsed time every frame to
+ *  find out how much the object should be moved.
+ *
+ * If you don't use GLWidget then you need to call nextFrame() every time that
+ *  another frame is rendered.
+ *
+ * The fps value is recalculated once a second.
+ *
+ * You can also use totalTimeElapsed() to find out how much time has elapsed
+ *  since nextFrame() was called the very first time.
+ *
+ * @see GLWidget
+ **/
 class KGLLIB_EXPORT FPSCounter
 {
 public:
+    /**
+     * Creates new FPS counter. The counter isn't started until nextFrame()
+     *  is called for the first time.
+     **/
     FPSCounter();
 
+    /**
+     * This method should be called whenever a frame is rendered. It increases
+     *  the internal counters and updates the calculated FPS value once a
+     *  second.
+     *
+     * @see fps(), timeElapsed()
+     **/
     void nextFrame();
     void resetTimeElapsed();
 
+    /**
+     * Returns the current FPS value.
+     *
+     * Note that the value is recalculated by nextFrame() about once a second.
+     *
+     * @see fpsString(), timeElapsed(), nextFrame()
+     **/
     float fps() const  { return mFPS; }
+    /**
+     * Returns the current FPS value as string.
+     *
+     * Number of significant digits in the string is kept at 3, so possible
+     *  return values include "123", "42.7" and "3.84".
+     *
+     * @see fps()
+     **/
     QString fpsString() const;
+    /**
+     * Returnes time elapsed between last two calls to nextFrame() method.
+     * Usually that gives you the time elapsed since last frame and could be
+     *  used e.g. for animation purposes.
+     *
+     * The return value is in seconds, thus a value of 0.075 would indicate
+     *  that 75 milliseconds have elapsed.
+     *
+     * @see fps()
+     **/
     // TODO: rename to timeSinceLastFrame()? change semantics?
     float timeElapsed() { return mTimeElapsed; }
+    /**
+     * Returns amount of time that has elapsed since the first call to
+     *  nextFrame().
+     *
+     * @see timeElapsed(), nextFrame()
+     **/
     float totalTimeElapsed()  { return mTotalTimeElapsed; }
 
 protected: