pyvisi/py_src/light.py

"""
@author: John NGUI
"""

import vtk
from position import GlobalPosition
from constant import Viewport

class Light:
    """
    Class that defines a light. A light controls the lighting for the
    rendered object and works in a similar way to L{Camera <camera.Camera>}.
    """

    # The SOUTH_WEST default viewport is used when there is only one viewport.
    # This saves the user from specifying the viewport when there is only one.
    def __init__(self, scene, data_collector, viewport = Viewport.SOUTH_WEST):
        """
        Initialise the light.

        @type scene: L{Scene <scene.Scene>} object
        @param scene: Scene in which components are to be added to  
        @type data_collector: L{DataCollector <datacollector.DataCollector>}
            object
        @param data_collector: Source of data for vizualization
        @type viewport: L{Viewport <constant.Viewport>} constant
        @param viewport: Viewport in which objects are to be rendered on
        """

        self.__scene = scene
        self.__data_collector = data_collector
        self.__viewport = viewport
        self.__vtk_light = vtk.vtkLight()

        self.__setupLight()

    def __setupLight(self):
        """
        Set up the light and associate it with the renderer.
        """

        self.__scene._addLight(self.__viewport, self.__vtk_light)

    def setColor(self, color):
        """
        Set the light color.

        @type color: L{Color <constant.Color>} constant
        @param color: Light color
        """

        self.__vtk_light.SetColor(color)

    def setFocalPoint(self, position):
        """
        Set the focal point of the light.

        @type position: L{GlobalPosition <position.GlobalPosition>} object
        @param position: Light focal point
        """

        self.__vtk_light.SetFocalPoint(position._getGlobalPosition())

    def setPosition(self, position):
        """
        Set the position of the light.

        @type position: L{GlobalPosition <position.GlobalPosition>} object
        @param position: Light position
        """

        self.__vtk_light.SetPosition(position._getGlobalPosition())

    # Elevation and azimuth is set to zero so that users do not 
    # have to change both at the same time.
    def setAngle(self, elevation = 0, azimuth = 0):
        """
        An alternative to set the position and focal point of the light 
        by using the elevation and azimuth. 

        @type elevation: Number
        @param elevation: Degree to rotate the light to the top and bottom
        @type azimuth: Number
        @param azimuth: Degree to rotate the light to the left and right
        """

        # NOTE: The elevation angle of light does not appear to suffer the same
        # constraint as the elevation angle of camera where the elevation
        # angle is constraint between 90/-90.
        self.__vtk_light.SetDirectionAngle(elevation, azimuth)

    def setIntensity(self, intensity):
        """
        Set the intensity (brightness) of the light.

        @type intensity: Number
        @param intensity: Intensity (brightness) of the light
        """

        self.__vtk_light.SetIntensity(intensity)

1	jongui	1037	"""
2			@author: John NGUI
3			"""
4
5			import vtk
6			from position import GlobalPosition
7			from constant import Viewport
8
9			class Light:
10			"""
11	jongui	1078	Class that defines a light. A light controls the lighting for the
12	jongui	1037	rendered object and works in a similar way to L{Camera <camera.Camera>}.
13			"""
14
15			# The SOUTH_WEST default viewport is used when there is only one viewport.
16			# This saves the user from specifying the viewport when there is only one.
17			def __init__(self, scene, data_collector, viewport = Viewport.SOUTH_WEST):
18			"""
19			Initialise the light.
20
21			@type scene: L{Scene <scene.Scene>} object
22			@param scene: Scene in which components are to be added to
23			@type data_collector: L{DataCollector <datacollector.DataCollector>}
24			object
25	jongui	1078	@param data_collector: Source of data for vizualization
26	jongui	1037	@type viewport: L{Viewport <constant.Viewport>} constant
27			@param viewport: Viewport in which objects are to be rendered on
28			"""
29
30			self.__scene = scene
31			self.__data_collector = data_collector
32			self.__viewport = viewport
33			self.__vtk_light = vtk.vtkLight()
34
35			self.__setupLight()
36
37			def __setupLight(self):
38			"""
39			Set up the light and associate it with the renderer.
40			"""
41
42			self.__scene._addLight(self.__viewport, self.__vtk_light)
43
44			def setColor(self, color):
45			"""
46			Set the light color.
47
48			@type color: L{Color <constant.Color>} constant
49			@param color: Light color
50			"""
51
52			self.__vtk_light.SetColor(color)
53
54			def setFocalPoint(self, position):
55			"""
56			Set the focal point of the light.
57
58			@type position: L{GlobalPosition <position.GlobalPosition>} object
59			@param position: Light focal point
60			"""
61
62			self.__vtk_light.SetFocalPoint(position._getGlobalPosition())
63
64			def setPosition(self, position):
65			"""
66			Set the position of the light.
67
68			@type position: L{GlobalPosition <position.GlobalPosition>} object
69			@param position: Light position
70			"""
71
72			self.__vtk_light.SetPosition(position._getGlobalPosition())
73
74	jongui	1078	# Elevation and azimuth is set to zero so that users do not
75	jongui	1037	# have to change both at the same time.
76			def setAngle(self, elevation = 0, azimuth = 0):
77			"""
78			An alternative to set the position and focal point of the light
79	jongui	1078	by using the elevation and azimuth.
80	jongui	1037
81			@type elevation: Number
82			@param elevation: Degree to rotate the light to the top and bottom
83			@type azimuth: Number
84			@param azimuth: Degree to rotate the light to the left and right
85			"""
86
87	jongui	1078	# NOTE: The elevation angle of light does not appear to suffer the same
88	jongui	1037	# constraint as the elevation angle of camera where the elevation
89			# angle is constraint between 90/-90.
90			self.__vtk_light.SetDirectionAngle(elevation, azimuth)
91
92			def setIntensity(self, intensity):
93			"""
94			Set the intensity (brightness) of the light.
95
96			@type intensity: Number
97			@param intensity: Intensity (brightness) of the light
98			"""
99
100			self.__vtk_light.SetIntensity(intensity)
101