Defines the list of pixel values to be considered as transparent or semi transparent when rendering rasters. More...

#include <qgsrastertransparency.h>

Classes
struct	TransparentSingleValuePixel
struct	TransparentThreeValuePixel
Public Member Functions
	QgsRasterTransparency ()
int	alphaValue (double, int theGlobalTransparency=255) const
	Returns the transparency value for a single value Pixel.
int	alphaValue (double, double, double, int theGlobalTransparency=255) const
	Return the transparency value for a RGB Pixel.
void	initializeTransparentPixelList (double)
	Reset to the transparency list to a single value.
void	initializeTransparentPixelList (double, double, double)
	Reset to the transparency list to a single value.
bool	isEmpty () const
	True if there are no entries in the pixel lists except the nodata value.
void	readXML (const QDomElement &elem)
void	setTransparentSingleValuePixelList (QList< QgsRasterTransparency::TransparentSingleValuePixel >)
	Mutator for transparentSingleValuePixelList.
void	setTransparentThreeValuePixelList (QList< QgsRasterTransparency::TransparentThreeValuePixel >)
	Mutator for transparentThreeValuePixelList.
QList < QgsRasterTransparency::TransparentSingleValuePixel >	transparentSingleValuePixelList () const
	Accessor for transparentSingleValuePixelList.
QList < QgsRasterTransparency::TransparentThreeValuePixel >	transparentThreeValuePixelList () const
	Accessor for transparentThreeValuePixelList.
void	writeXML (QDomDocument &doc, QDomElement &parentElem) const
Private Attributes
QList < QgsRasterTransparency::TransparentSingleValuePixel >	mTransparentSingleValuePixelList
	The list to hold transparency values for single value pixel layers.
QList < QgsRasterTransparency::TransparentThreeValuePixel >	mTransparentThreeValuePixelList
	The list to hold transparency values for RGB layers.

Detailed Description

Defines the list of pixel values to be considered as transparent or semi transparent when rendering rasters.

Definition at line 29 of file qgsrastertransparency.h.

Constructor & Destructor Documentation

QgsRasterTransparency::QgsRasterTransparency ( )

Definition at line 27 of file qgsrastertransparency.cpp.

Member Function Documentation

int QgsRasterTransparency::alphaValue	(	double	theValue,
		int	theGlobalTransparency = `255`
	)		const

Returns the transparency value for a single value Pixel.

Searches through the transparency list, if a match is found, the global transparency value is scaled by the stored transparency value.

Parameters:

theValue	the needle to search for in the transparency hay stack
theGlobalTransparency	the overal transparency level for the layer

Definition at line 104 of file qgsrastertransparency.cpp.

References QgsRasterTransparency::TransparentSingleValuePixel::max, QgsRasterTransparency::TransparentSingleValuePixel::min, mTransparentSingleValuePixelList, QgsRasterTransparency::TransparentSingleValuePixel::percentTransparent, and qgsDoubleNear().

Referenced by QgsPalettedRasterRenderer::block(), QgsSingleBandPseudoColorRenderer::block(), QgsMultiBandColorRenderer::block(), and QgsSingleBandGrayRenderer::block().

int QgsRasterTransparency::alphaValue	(	double	theRedValue,
		double	theGreenValue,
		double	theBlueValue,
		int	theGlobalTransparency = `255`
	)		const

Return the transparency value for a RGB Pixel.

Searches through the transparency list, if a match is found, the global transparency value is scaled by the stored transparency value.

Parameters:

theRedValue	the red portion of the needle to search for in the transparency hay stack
theGreenValue	the green portion of the needle to search for in the transparency hay stack
theBlueValue	the green portion of the needle to search for in the transparency hay stack
theGlobalTransparency	the overal transparency level for the layer

Definition at line 144 of file qgsrastertransparency.cpp.

References QgsRasterTransparency::TransparentThreeValuePixel::blue, QgsRasterTransparency::TransparentThreeValuePixel::green, mTransparentThreeValuePixelList, QgsRasterTransparency::TransparentThreeValuePixel::percentTransparent, and QgsRasterTransparency::TransparentThreeValuePixel::red.

void QgsRasterTransparency::initializeTransparentPixelList ( double theValue )

Reset to the transparency list to a single value.

Definition at line 51 of file qgsrastertransparency.cpp.

References QgsRasterTransparency::TransparentSingleValuePixel::max, QgsRasterTransparency::TransparentSingleValuePixel::min, mTransparentSingleValuePixelList, and QgsRasterTransparency::TransparentSingleValuePixel::percentTransparent.