Public Member Functions

GDALColorTable Class Reference

#include <gdal_priv.h>

List of all members.

Public Member Functions

 GDALColorTable (GDALPaletteInterp=GPI_RGB)
 Construct a new color table.
 ~GDALColorTable ()
 Destructor.
GDALColorTableClone () const
 Make a copy of a color table.
GDALPaletteInterp GetPaletteInterpretation () const
 Fetch palette interpretation.
int GetColorEntryCount () const
 Get number of color entries in table.
const GDALColorEntryGetColorEntry (int) const
 Fetch a color entry from table.
int GetColorEntryAsRGB (int, GDALColorEntry *) const
 Fetch a table entry in RGB format.
void SetColorEntry (int, const GDALColorEntry *)
 Set entry in color table.
int CreateColorRamp (int, const GDALColorEntry *, int, const GDALColorEntry *)
 Create color ramp.

Detailed Description

A color table / palette.


Constructor & Destructor Documentation

GDALColorTable::GDALColorTable ( GDALPaletteInterp  eInterpIn = GPI_RGB  ) 

Construct a new color table.

This constructor is the same as the C GDALCreateColorTable() function.

Parameters:
eInterpIn the interpretation to be applied to GDALColorEntry values.
GDALColorTable::~GDALColorTable (  ) 

Destructor.

This descructor is the same as the C GDALDestroyColorTable() function.


Member Function Documentation

GDALColorTable * GDALColorTable::Clone (  )  const

Make a copy of a color table.

This method is the same as the C function GDALCloneColorTable().

int GDALColorTable::CreateColorRamp ( int  nStartIndex,
const GDALColorEntry psStartColor,
int  nEndIndex,
const GDALColorEntry psEndColor 
)

Create color ramp.

Automatically creates a color ramp from one color entry to another. It can be called several times to create multiples ramps in the same color table.

This function is the same as the C function GDALCreateColorRamp().

Parameters:
nStartIndex index to start the ramp on the color table [0..255]
psStartColor a color entry value to start the ramp
nEndIndex index to end the ramp on the color table [0..255]
psEndColor a color entry value to end the ramp
Returns:
total number of entries, -1 to report error
const GDALColorEntry * GDALColorTable::GetColorEntry ( int  i  )  const

Fetch a color entry from table.

This method is the same as the C function GDALGetColorEntry().

Parameters:
i entry offset from zero to GetColorEntryCount()-1.
Returns:
pointer to internal color entry, or NULL if index is out of range.
int GDALColorTable::GetColorEntryAsRGB ( int  i,
GDALColorEntry poEntry 
) const

Fetch a table entry in RGB format.

In theory this method should support translation of color palettes in non-RGB color spaces into RGB on the fly, but currently it only works on RGB color tables.

This method is the same as the C function GDALGetColorEntryAsRGB().

Parameters:
i entry offset from zero to GetColorEntryCount()-1.
poEntry the existing GDALColorEntry to be overrwritten with the RGB values.
Returns:
TRUE on success, or FALSE if the conversion isn't supported.
int GDALColorTable::GetColorEntryCount (  )  const

Get number of color entries in table.

This method is the same as the function GDALGetColorEntryCount().

Returns:
the number of color entries.
GDALPaletteInterp GDALColorTable::GetPaletteInterpretation (  )  const

Fetch palette interpretation.

The returned value is used to interprete the values in the GDALColorEntry.

This method is the same as the C function GDALGetPaletteInterpretation().

Returns:
palette interpretation enumeration value, usually GPI_RGB.
void GDALColorTable::SetColorEntry ( int  i,
const GDALColorEntry poEntry 
)

Set entry in color table.

Note that the passed in color entry is copied, and no internal reference to it is maintained. Also, the passed in entry must match the color interpretation of the table to which it is being assigned.

The table is grown as needed to hold the supplied offset.

This function is the same as the C function GDALSetColorEntry().

Parameters:
i entry offset from zero to GetColorEntryCount()-1.
poEntry value to assign to table.

The documentation for this class was generated from the following files:

Generated for GDAL by doxygen 1.7.1.