pyvisi/py_src/transform.py

"""
@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"
__copyright__="""  Copyright (c) 2006 by ACcESS MNRF
                    http://www.access.edu.au
                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.iservo.edu.au/esys"
__version__="$Revision$"
__date__="$Date$"


import vtk

class Transform:
    """
    Class that defines the orientation of planes.
    
    @attention: There is a difference between performing rotation first 
    followed by translation, and performing translation first followed 
    by rotation.

    @attention: VTK's coordinate system and translation is NOT 100% precise. 
    Consequently, performing maximum rotation and translation can potentially
    yield incorrect results. For instance, rotating a XY plane along the x-axis 
    90 degrees may NOT produce any results (as it is possible that the XY 
    plane has just fallen outside the visible range). Therefore, rotating the 
    XY plane 89.9 degrees instead, should be a better option in order to 
    produce the correct results.
    """

    def __init__(self):
        """
        Initialise the transform object.
        """

        # NOTE: VTK's coordinates are not 100% precise. The origin is not 
        # exaclty (0,0,0) and the normal is not exactly (0, 0, 1). There is a 
        # slight variance. As a result, a slight alteration has to be done 
        # in order for the plane to be displayed correctly. Otherwise, the 
        # plane may just fall outside the bounding box and nothing 
        # is displayed.  
        self.__OFFSET_VARIANCE = 0.0000000001
        self.__vtk_transform = vtk.vtkTransform()

    def translate(self, x_offset, y_offset, z_offset):
        """
        Translate the rendered object along the x, y and z-axes.

        @type x_offset: Number
        @param x_offset: Amount to translate along the x-axis
        @type y_offset: Number
        @param y_offset: Amount to translate along the y-axis
        @type z_offset: Number
        @param z_offset: Amount to translate along the z-axis 
        """

        self.__vtk_transform.Translate(-x_offset, -y_offset, -z_offset)
    
    def rotateX(self, angle):
        """
        Rotate the plane along the x-axis.

        @type angle: Number
        @param angle: Angle to rotate the plane
        """

        self.__vtk_transform.RotateX(-angle)

    def rotateY(self, angle):
        """
        Rotate the plane along the y-axis.

        @type angle: Number
        @param angle: Angle to rotate the plane
        """

        self.__vtk_transform.RotateY(angle)

    def rotateZ(self, angle):
        """
        Rotate the plane along the z-axis.

        @type angle: Number
        @param angle: Angle to rotate the plane
        """

        self.__vtk_transform.RotateZ(angle)

    def setPlaneToXY(self, offset = 0):
        """
        Set the plane orthogonal to the z-axis.

        @type offset: Number
        @param offset: Amount to translate along the z-axis
        """
    
        self.translate(0, 0, offset + self.__OFFSET_VARIANCE)

    def setPlaneToYZ(self, offset = 0):
        """
        Set the plane orthogonal to the x-axis.

        @type offset: Number
        @param offset: Amount to translate along the x-axis
        """
        
        # NOTE: rotateY must come first before translate. Otherwise, 
        # the output may be incorrect.
        self.rotateY(90) 
        self.translate(offset, 0, 0)

    def setPlaneToXZ(self, offset = 0):
        """
        Set the plane orthogonal to the y-axis.

        @type offset: Number
        @param offset: Amount to translate along the y-axis
        """

        # rotateX must come first before translate. Otherwise, it won't work.
        self.rotateX(90)
        self.translate(0, offset, 0)
    
    def _getTransform(self):
        """
        Return the transform instance.

        @rtype: vtkTransform
        @return: Transform instance that is used to specify the orientation
            of the plane
        """

        return self.__vtk_transform


###############################################################################


class TransformFilter:
    """
    Class that defines a transform poly data filter.
    """

    def __init__(self):
        """
        Initialise the transoform poly data filter.
        """

        self.__vtk_transform_filter = vtk.vtkTransformPolyDataFilter()

    def _setupTransformFilter(self, plane_source, transform):
        """
        Setup the transform filter.

        @type plane_source: vtkPolyData
        @param plane_source: Polygonal data
        @type transform: L{Transform <transform.Transform>} object
        @param transform: Specifies the orientation of the plane source
        """

        self.__plane_source = plane_source
        self.__transform = transform

        self.__setInput()
        self.__setTransform()

    def __setInput(self):
        """
        Set the input for the transform poly data filter.
        """

        self.__vtk_transform_filter.SetInput(self.__plane_source)

    def __setTransform(self):
        """
        Set the transformation of the plane source.
        """

        self.__vtk_transform_filter.SetTransform(self.__transform)

    def _getTransformFilterOutput(self):
        """
        Return the output of the transform poly data filter.
        """

        return self.__vtk_transform_filter.GetOutput()


1	ksteube	1147	"""
2	jongui	1197	@var __author__: name of author
3			@var __copyright__: copyrights
4			@var __license__: licence agreement
5			@var __url__: url entry point on documentation
6			@var __version__: version
7			@var __date__: date of the version
8	ksteube	1147	"""
9
10	jongui	1197	__author__="John Ngui, john.ngui@uq.edu.au"
11			__copyright__=""" Copyright (c) 2006 by ACcESS MNRF
12			http://www.access.edu.au
13			Primary Business: Queensland, Australia"""
14			__license__="""Licensed under the Open Software License version 3.0
15			http://www.opensource.org/licenses/osl-3.0.php"""
16			__url__="http://www.iservo.edu.au/esys"
17			__version__="$Revision$"
18			__date__="$Date$"
19
20
21	ksteube	1147	import vtk
22
23			class Transform:
24			"""
25			Class that defines the orientation of planes.
26
27			@attention: There is a difference between performing rotation first
28			followed by translation, and performing translation first followed
29			by rotation.
30
31	jongui	1199	@attention: VTK's coordinate system and translation is NOT 100% precise.
32	ksteube	1147	Consequently, performing maximum rotation and translation can potentially
33			yield incorrect results. For instance, rotating a XY plane along the x-axis
34			90 degrees may NOT produce any results (as it is possible that the XY
35	jongui	1199	plane has just fallen outside the visible range). Therefore, rotating the
36			XY plane 89.9 degrees instead, should be a better option in order to
37			produce the correct results.
38	ksteube	1147	"""
39
40			def __init__(self):
41			"""
42			Initialise the transform object.
43			"""
44
45	jongui	1199	# NOTE: VTK's coordinates are not 100% precise. The origin is not
46	ksteube	1147	# exaclty (0,0,0) and the normal is not exactly (0, 0, 1). There is a
47			# slight variance. As a result, a slight alteration has to be done
48			# in order for the plane to be displayed correctly. Otherwise, the
49			# plane may just fall outside the bounding box and nothing
50			# is displayed.
51			self.__OFFSET_VARIANCE = 0.0000000001
52			self.__vtk_transform = vtk.vtkTransform()
53
54			def translate(self, x_offset, y_offset, z_offset):
55			"""
56			Translate the rendered object along the x, y and z-axes.
57
58			@type x_offset: Number
59			@param x_offset: Amount to translate along the x-axis
60			@type y_offset: Number
61			@param y_offset: Amount to translate along the y-axis
62			@type z_offset: Number
63			@param z_offset: Amount to translate along the z-axis
64			"""
65
66			self.__vtk_transform.Translate(-x_offset, -y_offset, -z_offset)
67
68			def rotateX(self, angle):
69			"""
70			Rotate the plane along the x-axis.
71
72			@type angle: Number
73			@param angle: Angle to rotate the plane
74			"""
75
76			self.__vtk_transform.RotateX(-angle)
77
78			def rotateY(self, angle):
79			"""
80			Rotate the plane along the y-axis.
81
82			@type angle: Number
83			@param angle: Angle to rotate the plane
84			"""
85
86			self.__vtk_transform.RotateY(angle)
87
88			def rotateZ(self, angle):
89			"""
90			Rotate the plane along the z-axis.
91
92			@type angle: Number
93			@param angle: Angle to rotate the plane
94			"""
95
96			self.__vtk_transform.RotateZ(angle)
97
98			def setPlaneToXY(self, offset = 0):
99			"""
100			Set the plane orthogonal to the z-axis.
101
102			@type offset: Number
103			@param offset: Amount to translate along the z-axis
104			"""
105
106			self.translate(0, 0, offset + self.__OFFSET_VARIANCE)
107
108			def setPlaneToYZ(self, offset = 0):
109			"""
110			Set the plane orthogonal to the x-axis.
111
112			@type offset: Number
113			@param offset: Amount to translate along the x-axis
114			"""
115
116			# NOTE: rotateY must come first before translate. Otherwise,
117			# the output may be incorrect.
118			self.rotateY(90)
119			self.translate(offset, 0, 0)
120
121			def setPlaneToXZ(self, offset = 0):
122			"""
123			Set the plane orthogonal to the y-axis.
124
125			@type offset: Number
126			@param offset: Amount to translate along the y-axis
127			"""
128
129			# rotateX must come first before translate. Otherwise, it won't work.
130			self.rotateX(90)
131			self.translate(0, offset, 0)
132
133			def _getTransform(self):
134			"""
135			Return the transform instance.
136
137			@rtype: vtkTransform
138			@return: Transform instance that is used to specify the orientation
139			of the plane
140			"""
141
142			return self.__vtk_transform
143
144
145			###############################################################################
146
147
148			class TransformFilter:
149			"""
150			Class that defines a transform poly data filter.
151			"""
152
153	jongui	1148	def __init__(self):
154	ksteube	1147	"""
155			Initialise the transoform poly data filter.
156	jongui	1148	"""
157	ksteube	1147
158	jongui	1148	self.__vtk_transform_filter = vtk.vtkTransformPolyDataFilter()
159
160			def _setupTransformFilter(self, plane_source, transform):
161			"""
162			Setup the transform filter.
163
164	ksteube	1147	@type plane_source: vtkPolyData
165			@param plane_source: Polygonal data
166			@type transform: L{Transform <transform.Transform>} object
167			@param transform: Specifies the orientation of the plane source
168			"""
169
170			self.__plane_source = plane_source
171			self.__transform = transform
172
173	jongui	1148	self.__setInput()
174			self.__setTransform()
175	ksteube	1147
176	jongui	1148	def __setInput(self):
177	ksteube	1147	"""
178			Set the input for the transform poly data filter.
179			"""
180
181			self.__vtk_transform_filter.SetInput(self.__plane_source)
182
183	jongui	1148	def __setTransform(self):
184	ksteube	1147	"""
185			Set the transformation of the plane source.
186			"""
187
188			self.__vtk_transform_filter.SetTransform(self.__transform)
189
190	jongui	1148	def _getTransformFilterOutput(self):
191	ksteube	1147	"""
192			Return the output of the transform poly data filter.
193			"""
194
195			return self.__vtk_transform_filter.GetOutput()
196
197
198