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	"""
2	@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	"""
9
10	__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	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	@attention: VTK's coordinate system and translation is NOT 100% precise.
32	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	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	"""
39
40	def __init__(self):
41	"""
42	Initialise the transform object.
43	"""
44
45	# NOTE: VTK's coordinates are not 100% precise. The origin is not
46	# 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	def __init__(self):
154	"""
155	Initialise the transoform poly data filter.
156	"""
157
158	self.__vtk_transform_filter = vtk.vtkTransformPolyDataFilter()
159
160	def _setupTransformFilter(self, plane_source, transform):
161	"""
162	Setup the transform filter.
163
164	@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	self.__setInput()
174	self.__setTransform()
175
176	def __setInput(self):
177	"""
178	Set the input for the transform poly data filter.
179	"""
180
181	self.__vtk_transform_filter.SetInput(self.__plane_source)
182
183	def __setTransform(self):
184	"""
185	Set the transformation of the plane source.
186	"""
187
188	self.__vtk_transform_filter.SetTransform(self.__transform)
189
190	def _getTransformFilterOutput(self):
191	"""
192	Return the output of the transform poly data filter.
193	"""
194
195	return self.__vtk_transform_filter.GetOutput()
196
197
198