pyvisi/py_src/lookuptable.py


########################################################
#
# Copyright (c) 2003-2008 by University of Queensland
# Earth Systems Science Computational Center (ESSCC)
# http://www.uq.edu.au/esscc
#
# Primary Business: Queensland, Australia
# Licensed under the Open Software License version 3.0
# http://www.opensource.org/licenses/osl-3.0.php
#
########################################################

__copyright__="""Copyright (c) 2003-2008 by University of Queensland
Earth Systems Science Computational Center (ESSCC)
http://www.uq.edu.au/esscc
Primary Business: Queensland, Australia"""
__license__="""Licensed under the Open Software License version 3.0
http://www.opensource.org/licenses/osl-3.0.php"""
__url__="http://www.uq.edu.au/esscc/escript-finley"

"""
@var __author__: name of author
@var __copyright__: copyrights
@var __license__: licence agreement
@var __url__: url entry point on documentation
@var __version__: version
@var __date__: date of the version
"""

__author__="John Ngui, john.ngui@uq.edu.au"

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
2	########################################################
3	#
4	# Copyright (c) 2003-2008 by University of Queensland
5	# Earth Systems Science Computational Center (ESSCC)
6	# http://www.uq.edu.au/esscc
7	#
8	# Primary Business: Queensland, Australia
9	# Licensed under the Open Software License version 3.0
10	# http://www.opensource.org/licenses/osl-3.0.php
11	#
12	########################################################
13
14	__copyright__="""Copyright (c) 2003-2008 by University of Queensland
15	Earth Systems Science Computational Center (ESSCC)
16	http://www.uq.edu.au/esscc
17	Primary Business: Queensland, Australia"""
18	__license__="""Licensed under the Open Software License version 3.0
19	http://www.opensource.org/licenses/osl-3.0.php"""
20	__url__="http://www.uq.edu.au/esscc/escript-finley"
21
22	"""
23	@var __author__: name of author
24	@var __copyright__: copyrights
25	@var __license__: licence agreement
26	@var __url__: url entry point on documentation
27	@var __version__: version
28	@var __date__: date of the version
29	"""
30
31	__author__="John Ngui, john.ngui@uq.edu.au"
32
33	import vtk
34
35	class LookupTable:
36	"""
37	Class that defines a lookup table for mapping scalar values into colors.
38	"""
39
40	def __init__(self):
41	"""
42	Initialise the lookup table.
43	"""
44
45	self.__vtk_lookup_table = vtk.vtkLookupTable()
46	self.__vtk_inverse_lookup_table = vtk.vtkLookupTable()
47	self.__build()
48
49	def __build(self):
50	"""
51	Generates the lookup table.
52	"""
53
54	# NOTE: Build have to be executed prior to using SetTableValue (if any).
55	self.__vtk_lookup_table.Build()
56	self.__vtk_inverse_lookup_table.Build()
57
58	def _setTableValue(self):
59	"""
60	Setup the lookup table with colors.
61	"""
62
63	# NOTE: The color values are inversed because VTK's default lookup
64	# table is inversed by itself. SetTableValue have to be executed after
65	# the Build.
66	for i in range(256):
67	self.__vtk_lookup_table.SetTableValue(
68	i, self.__vtk_inverse_lookup_table.GetTableValue(255 - i))
69
70	def _setLookupTableToGreyScale(self):
71	"""
72	Setup the lookup table with grey scale.
73	"""
74
75	self.__setHueRange(0,0)
76	self.__setSaturationRange(0,0)
77	self.__setValueRange(1,0)
78	self.__setNumberOfTableValues(256)
79	self.__setRampToSQRT()
80
81	def __setValueRange(self, lower_range, upper_range):
82	"""
83	Set the value range (brightness) for the lookup table (between 0 and 1).
84
85	@type lower_range: Number
86	@param lower_range:Lower value range
87	@type upper_range: Number
88	@param upper_range: Upper value range
89	"""
90
91	self.__vtk_lookup_table.SetValueRange(lower_range, upper_range)
92
93	def __setHueRange(self, lower_range, upper_range):
94	"""
95	Set the hue (color) range for the lookup table (between 0 and 1).
96
97	@type lower_range: Number
98	@param lower_range:Lower hue range
99	@type upper_range: Number
100	@param upper_range: Upper hue range
101	"""
102
103	self.__vtk_lookup_table.SetHueRange(lower_range, upper_range)
104
105	def __setSaturationRange(self, lower_range, upper_range):
106	"""
107	Set the saturation (vibrancy) range for the lookup table \
108	(between 0 and 1).
109
110	@type lower_range: Number
111	@param lower_range:Lower saturantion range
112	@type upper_range: Number
113	@param upper_range: Upper saturation range
114	"""
115
116	self.__vtk_lookup_table.SetSaturationRange(lower_range, upper_range)
117
118	def __setRampToSQRT(self):
119	"""
120	Set the table ramp to SQRT. The default ramp is S-curve.
121	"""
122
123	self.__vtk_lookup_table.SetRampToSQRT()
124
125	def __setNumberOfTableValues(self, table_values):
126	"""
127	Set the number of values (i.e. colors) in the lookup table.
128
129	@type table_values: Number
130	@param table_values: Number of colors in the lookup table.
131	"""
132
133	self.__vtk_lookup_table.SetNumberOfTableValues(table_values)
134
135	def _getLookupTable(self):
136	"""
137	Return the lookup table.
138
139	@rtype: vtkLookupTable
140	@return: Lookup table
141	"""
142
143	return self.__vtk_lookup_table
144
145
146