--- a/include/sampler.h	Tue May 06 09:39:58 2008 +0200
+++ b/include/sampler.h	Thu May 08 09:21:25 2008 +0200
@@ -1,5 +1,6 @@
-/*
- * sampler.h: screen sample generation and image reconstruction
+/**
+ * @file  sampler.h
+ * @brief Screen sample generation and image reconstruction
  *
  * This file is part of Pyrit Ray Tracer.
  *
@@ -34,70 +35,151 @@
 using namespace std;
 
 /**
- * sample
+ * A structure containing sample's coordinates.
  */
 class Sample
 {
-	friend class Sampler;
 public:
+	//@{
+	/**
+	 * Generated coordinates.
+	 *
+	 * These are coordinates for use by Camera.
+	 * Middle of the screen plane has [0,0],
+	 * top of the screen has y=-0.5, left pixels has x<0
+	 * and the rest of samples are aligned to regular grid,
+	 * so the vertical size is always one and horizontal size
+	 * can be wider depending on aspect ratio.
+	 */
 	Float x,y;
+	//@}
+
+	//@{
+	/**
+	 * Auxiliary coordinates used internally by sampler.
+	 *
+	 * Screen coordinates sx, sy are integer coordinates of screen pixels,
+	 * osa_samp is used by oversampling to remember current sample.
+	 */
 	int sx,sy,osa_samp;
+	//@}
 };
 
 /**
  * A abstract sampler.
- * It generates screen samples in coordinates between [-1..1] for height
- * and [-w/h..w/h] for width. It works in phases: initSampleSet returns
+ *
+ * It generates screen samples in coordinates between [-0.5..0.5] for height
+ * and [-w/h/2..w/h/2] for width. It works in phases: initSampleSet returns
  * number of samples for each phase, then samples can be generated using
  * nextSample method. The resulting colour of each sample should be returned
  * via saveSample method. The sampler should save the results to given buffer
- * and decide if other phase is needed. When the picture is complete,
+ * and decide if another phase is needed. When the picture is complete,
  * initSampleSet returns zero and picture can be read from buffer.
  */
 class Sampler
 {
 protected:
-	Pixmap pixmap;
-	bool packetable;
+	Pixmap pixmap;    ///< A pixmap for resulting image.
+	bool packetable;  ///< True if the generated samples are usable with ray packets.
 public:
+	/** Constructor with user provided image buffer. */
 	Sampler(Float *buffer, const int &w, const int &h):
 		pixmap(buffer, w, h), packetable(false) {};
+
+	/** With this constructor, image buffer is allocated as specified by w,h. */
 	Sampler(const int &w, const int &h):
 		pixmap(w, h), packetable(false) {};
+
 	virtual ~Sampler() {};
+
+	/** Switch to new user provided buffer. */
 	void resetBuffer(Float *buffer, int &w, int &h)
 		{ pixmap.setData(buffer, w, h); };
+
+	/**
+	 * Initialize the sampler.
+	 *
+	 * This must be called first when starting new image.
+	 */
 	virtual void init() = 0;
+
+	/**
+	 * Prepare for next phase.
+	 *
+	 * Must be called before reading samples.
+	 * @retval N approximate number of samples to be generated in the phase
+	 * @retval 0 last phase, image is complete
+	 */
 	virtual int initSampleSet() = 0;
+
+	/**
+	 * Generate next sample.
+	 *
+	 * @param[out] s  The sample.
+	 * @retval false  No more samples in this phase.
+	 */
 	virtual bool nextSample(Sample *s) = 0;
-	virtual void saveSample(Sample &samp, Colour &col) = 0;
+
+	/**
+	 * Save the color of the sample.
+	 *
+	 * @param[in] samp  A sample.
+	 * @param[in] col   Color resulted from ray tracing the sample.
+	 */
+	virtual void saveSample(const Sample &samp, const Colour &col) = 0;
+
+	/** True if generated samples are usable with ray packets. */
 	bool packetableSamples() { return packetable; };
+
+	/** Get the pixmap. */
 	const Pixmap &getPixmap() const { return pixmap; };
 };
 
 /**
  * Default sampler.
+ *
  * Implements basic adaptive subsampling and oversampling.
  */
 class DefaultSampler: public Sampler
 {
-	int phase;
-	int subsample;  // 0,1 = no, 1+ = size of sampling grid
-	int oversample; // 0 = no, 1 = 4x, 2 = 9x, 3 = 16x
-	int sx,sy,osa_samp; // current sample properties
+	int phase;      ///< Current phase
+	int subsample;  ///< Subsampling mode
+	int oversample; ///< Oversampling mode
+	//@{
+	/** Properties of last generated sample. */
+	int sx,sy,osa_samp;
+	//@}
 public:
+	/** Constructor with user provided image buffer. */
 	DefaultSampler(Float *buffer, const int &w, const int &h):
 		Sampler(buffer, w, h), phase(-1), subsample(0), oversample(0) {};
+
+	/** With this constructor, image buffer is allocated as specified by w,h. */
 	DefaultSampler(const int &w, const int &h):
 		Sampler(w, h), phase(-1), subsample(0), oversample(0) {};
+
+	/* Implement virtuals from Sampler. */
 	void init();
 	int initSampleSet();
 	bool nextSample(Sample *s);
-	void saveSample(Sample &samp, Colour &col);
+	void saveSample(const Sample &samp, const Colour &col);
 
+	/**
+	  * Set subsampling mode.
+	  *
+	  * @param[in] sub  0,1 = no, 1+ = size of sampling grid
+	  */
 	void setSubsample(int sub) { subsample = sub; };
+	/** Get subsampling mode. @see setSubsample */
 	int getSubsample() { return subsample; };
+
+	/**
+	  * Set oversampling mode.
+	  *
+	  * @param[in] osa  0 = no, 1 = 4x, 2 = 9x, 3 = 16x
+	  */
 	void setOversample(int osa) { oversample = osa; };
+	/** Get oversampling mode. @see setOversample */
 	int getOversample() { return oversample; };
 };