pyvisi/py_src/lookuptable.py

"""
@author: John NGUI
"""

import vtk

class LookupTable:
    """
    Class that defines a lookup table for mapping scalar values into colors.
    """

    def __init__(self):
        """
        Initialise the lookup table.
        """

        self.__vtk_lookup_table = vtk.vtkLookupTable()
        self.__vtk_inverse_lookup_table = vtk.vtkLookupTable()
        self.__build()

    def __build(self):
        """
        Generates the lookup table.
        """

        # NOTE: Build have to be executed prior to using SetTableValue (if any).
        self.__vtk_lookup_table.Build()
        self.__vtk_inverse_lookup_table.Build()

    def _setTableValue(self):
        """
        Setup the lookup table with colors.
        """

        # NOTE: The color values are inversed because VTK's default lookup
        # table is inversed by itself. SetTableValue have to be executed after
        # the Build.
        for i in range(256):
            self.__vtk_lookup_table.SetTableValue(
                    i, self.__vtk_inverse_lookup_table.GetTableValue(255 - i))

    def _setLookupTableToGreyScale(self):
        """
        Setup the lookup table with grey scale. 
        """

        self.__setHueRange(0,0)
        self.__setSaturationRange(0,0)
        self.__setValueRange(1,0)
        self.__setNumberOfTableValues(256)
        self.__setRampToSQRT()

    def __setValueRange(self, lower_range, upper_range):
        """
        Set the value range (brightness) for the lookup table (between 0 and 1).

        @type lower_range: Number
        @param lower_range:Lower value range 
        @type upper_range: Number
        @param upper_range: Upper value range
        """

        self.__vtk_lookup_table.SetValueRange(lower_range, upper_range)

    def __setHueRange(self, lower_range, upper_range):
        """
        Set the hue (color) range for the lookup table (between 0 and 1).

        @type lower_range: Number
        @param lower_range:Lower hue range 
        @type upper_range: Number
        @param upper_range: Upper hue range
        """

        self.__vtk_lookup_table.SetHueRange(lower_range, upper_range)

    def __setSaturationRange(self, lower_range, upper_range):
        """
        Set the saturation (vibrancy) range for the lookup table \
        (between 0 and 1).

        @type lower_range: Number
        @param lower_range:Lower saturantion range 
        @type upper_range: Number
        @param upper_range: Upper saturation range
        """

        self.__vtk_lookup_table.SetSaturationRange(lower_range, upper_range)
    
    def __setRampToSQRT(self):
        """
        Set the table ramp to SQRT. The default ramp is S-curve.    
        """

        self.__vtk_lookup_table.SetRampToSQRT()

    def __setNumberOfTableValues(self, table_values):
        """
        Set the number of values (i.e. colors) in the lookup table. 

        @type table_values: Number
        @param table_values: Number of colors in the lookup table.
        """

        self.__vtk_lookup_table.SetNumberOfTableValues(table_values)

    def _getLookupTable(self):
        """
        Return the lookup table.

        @rtype: vtkLookupTable
        @return: Lookup table
        """

        return self.__vtk_lookup_table
    


1	ksteube	1147	"""
2			@author: John NGUI
3			"""
4
5			import vtk
6
7			class LookupTable:
8			"""
9			Class that defines a lookup table for mapping scalar values into colors.
10			"""
11
12			def __init__(self):
13			"""
14			Initialise the lookup table.
15			"""
16
17			self.__vtk_lookup_table = vtk.vtkLookupTable()
18			self.__vtk_inverse_lookup_table = vtk.vtkLookupTable()
19			self.__build()
20
21			def __build(self):
22			"""
23			Generates the lookup table.
24			"""
25
26			# NOTE: Build have to be executed prior to using SetTableValue (if any).
27			self.__vtk_lookup_table.Build()
28			self.__vtk_inverse_lookup_table.Build()
29
30			def _setTableValue(self):
31			"""
32			Setup the lookup table with colors.
33			"""
34
35			# NOTE: The color values are inversed because VTK's default lookup
36			# table is inversed by itself. SetTableValue have to be executed after
37			# the Build.
38			for i in range(256):
39			self.__vtk_lookup_table.SetTableValue(
40			i, self.__vtk_inverse_lookup_table.GetTableValue(255 - i))
41
42			def _setLookupTableToGreyScale(self):
43			"""
44			Setup the lookup table with grey scale.
45			"""
46
47			self.__setHueRange(0,0)
48			self.__setSaturationRange(0,0)
49			self.__setValueRange(1,0)
50			self.__setNumberOfTableValues(256)
51			self.__setRampToSQRT()
52
53			def __setValueRange(self, lower_range, upper_range):
54			"""
55			Set the value range (brightness) for the lookup table (between 0 and 1).
56
57			@type lower_range: Number
58			@param lower_range:Lower value range
59			@type upper_range: Number
60			@param upper_range: Upper value range
61			"""
62
63			self.__vtk_lookup_table.SetValueRange(lower_range, upper_range)
64
65			def __setHueRange(self, lower_range, upper_range):
66			"""
67			Set the hue (color) range for the lookup table (between 0 and 1).
68
69			@type lower_range: Number
70			@param lower_range:Lower hue range
71			@type upper_range: Number
72			@param upper_range: Upper hue range
73			"""
74
75			self.__vtk_lookup_table.SetHueRange(lower_range, upper_range)
76
77			def __setSaturationRange(self, lower_range, upper_range):
78			"""
79			Set the saturation (vibrancy) range for the lookup table \
80			(between 0 and 1).
81
82			@type lower_range: Number
83			@param lower_range:Lower saturantion range
84			@type upper_range: Number
85			@param upper_range: Upper saturation range
86			"""
87
88			self.__vtk_lookup_table.SetSaturationRange(lower_range, upper_range)
89
90			def __setRampToSQRT(self):
91			"""
92			Set the table ramp to SQRT. The default ramp is S-curve.
93			"""
94
95			self.__vtk_lookup_table.SetRampToSQRT()
96
97			def __setNumberOfTableValues(self, table_values):
98			"""
99			Set the number of values (i.e. colors) in the lookup table.
100
101			@type table_values: Number
102			@param table_values: Number of colors in the lookup table.
103			"""
104
105			self.__vtk_lookup_table.SetNumberOfTableValues(table_values)
106
107			def _getLookupTable(self):
108			"""
109	jongui	1148	Return the lookup table.
110
111	ksteube	1147	@rtype: vtkLookupTable
112			@return: Lookup table
113			"""
114
115			return self.__vtk_lookup_table
116	jongui	1189
117	ksteube	1147
118