Api documentation updates - added class descriptions for all raster classes

git-svn-id: http://svn.osgeo.org/qgis/trunk@9226 c8812cc2-4d05-0410-92ff-de0c093fc19c

Author: timlinux

src/core/qgsdistancearea.h

@@ -23,7 +23,7 @@
 class QgsGeometry;
 
 /** \ingroup core
-General purpose distance and area calculator
+General purpose distance and area calculator.
 - calculations are done on ellipsoid
 - it's possible to pass points/features in any CRS, coordinates are transformed
 - two options how to use it

src/core/raster/qgscliptominmaxenhancement.h

@@ -21,6 +21,12 @@ email                : ersts@amnh.org
 
 #include "qgscontrastenhancementfunction.h"
 
+/** \ingroup core
+ * A raster contrast enhancement that will clip a value to the specified min/max range.
+ * For example if a min max range of [10,240] is specified in the constructor, and 
+ * a value of 250 is called using enhanceValue(), the value will be truncated ('clipped') 
+ * to 240.
+ */
 class CORE_EXPORT QgsClipToMinMaxEnhancement : public QgsContrastEnhancementFunction
 {
 

src/core/raster/qgscolorrampshader.h

@@ -25,6 +25,9 @@ originally part of the larger QgsRasterLayer class
 
 #include "qgsrastershaderfunction.h"
 
+/** \ingroup core
+ * A ramp shader will color a raster pixel based on a list of values ranges in a ramp.
+ */
 class CORE_EXPORT QgsColorRampShader : public QgsRasterShaderFunction
 {
 

src/core/raster/qgscolortable.h

@@ -19,15 +19,6 @@
 
 #include <QVector>
 
-/*
- * Because of performance, this class can store color rules in 2 forms:
- *   1) discrete - vector of descrete values and their colors; can be accessed by index (from 0)
- *   2) ramp - vector of ramps defined by min and max value and a color for min amd max value,
- *             colors between min and max are interpolated linearly.
- *
- * Only one type should be used for one instance.
- *
- */
 
 
 typedef struct
@@ -41,6 +32,18 @@ typedef struct
   unsigned char min_c1, min_c2, min_c3, min_c4;
   unsigned char max_c1, max_c2, max_c3, max_c4;
 } RAMP;
+
+/** \ingroup core
+ * A raster color table contains a list of indexed values and the color associated with each index.
+ * Because of performance, this class can store color rules in 2 forms:
+ *   1) discrete - vector of descrete values and their colors; can be accessed by index (from 0)
+ *   2) ramp - vector of ramps defined by min and max value and a color for min amd max value,
+ *             colors between min and max are interpolated linearly.
+ *
+ * Only one type should be used for one instance.
+ *
+ */
+
 class CORE_EXPORT QgsColorTable
 {
   public:

src/core/raster/qgscontrastenhancement.cpp

@@ -28,8 +28,6 @@ class originally created circa 2004 by T.Sutton, Gary E.Sherman, Steve Halasz
 
 QgsContrastEnhancement::QgsContrastEnhancement( QgsRasterDataType theDataType )
 {
-  QgsDebugMsg( "called" );
-
   mLookupTable = 0;
   mContrastEnhancementFunction = 0;
   mEnhancementDirty = false;

src/core/raster/qgscontrastenhancement.h

@@ -25,6 +25,11 @@ class originally created circa 2004 by T.Sutton, Gary E.Sherman, Steve Halasz
 
 class QgsContrastEnhancementFunction;
 
+/** \ingroup core
+ * Manipulates raster pixel values so that they stretch or clip into a
+ * specified numerical range according to the specified
+ * CONTRAST_ENHANCEMENT_ALGORITHM.
+ */
 class CORE_EXPORT QgsContrastEnhancement
 {
 

src/core/raster/qgscontrastenhancementfunction.h

@@ -21,6 +21,12 @@ email                : ersts@amnh.org
 
 #include "qgscontrastenhancement.h"
 
+/** \ingroup core
+ * A contrast enhancement funcion is the base class for all raster contrast enhancements.
+ *
+ * The purpose of a contrast enhancement is to stretch or clip a pixel value into
+ * a specified bounding range.
+ */
 class CORE_EXPORT QgsContrastEnhancementFunction
 {
 

src/core/raster/qgsfreakoutshader.h

@@ -23,6 +23,9 @@ class originally created circa 2004 by T.Sutton, Gary E.Sherman, Steve Halasz
 
 #include "qgsrastershaderfunction.h"
 
+/** \ingroup core
+  * A colorful false color shader that will frighten your granny and make your dogs howl.
+  */
 class CORE_EXPORT QgsFreakOutShader : public QgsRasterShaderFunction
 {
 

src/core/raster/qgslinearminmaxenhancement.h

@@ -21,6 +21,9 @@ email                : ersts@amnh.org
 
 #include "qgscontrastenhancementfunction.h"
 
+/** \ingroup core
+  * A colour enhancement function that performs a linear stretch between min and max.
+  */
 class CORE_EXPORT QgsLinearMinMaxEnhancement : public QgsContrastEnhancementFunction
 {
 

src/core/raster/qgslinearminmaxenhancementwithclip.h

@@ -21,6 +21,10 @@ email                : ersts@amnh.org
 
 #include "qgscontrastenhancementfunction.h"
 
+/** \ingroup core
+ * A linear stretch enhancement that first clips to min max and then stretches
+ * linearly between min and max.
+ */
 class CORE_EXPORT QgsLinearMinMaxEnhancementWithClip : public QgsContrastEnhancementFunction
 {