Documentation for vtkLogLookupTable

vtkLogLookupTable - map scalar values into colors using logarithmic (base 10) color table

Description:

vtkLogLookupTable is an object that is used by mapper objects to map scalar values into rgba (red-green-blue-alpha transparency) color specification, or rgba into scalar values. The difference between this class and its superclass vtkLookupTable is that this class performs scalar mapping based on a logarithmic lookup process. (Uses log base 10.) If non-positive ranges are encountered, then they are converted to positive values using absolute value.

See Also:

vtkLookupTable

Methods:

	void vtkLogLookupTable (int ,int )
	static vtkLogLookupTable *New ()
	const char *GetClassName ()
	void PrintSelf (unknown & ,vtkIndent )
	void SetTableRange (float ,float )
	unsigned char *MapValue (float )

Detailed Method Descriptions:

Set the minimum/maximum scalar values for scalar mapping. Scalar values less than minimum range value are clamped to minimum range value. Scalar values greater than maximum range value are clamped to maximum range value. (The log base 10 of these values is taken and mapping is performed in logarithmic space.)

void SetTableRange (float ,float )

Given a scalar value v, return an rgba color value from lookup table. Mapping performed log base 10 (negative ranges are converted into positive values).

unsigned char *MapValue (float )