1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
|
/**************************************************************************\
*
* This file is part of the Coin 3D visualization library.
* Copyright (C) by Kongsberg Oil & Gas Technologies.
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* ("GPL") version 2 as published by the Free Software Foundation.
* See the file LICENSE.GPL at the root directory of this source
* distribution for additional information about the GNU GPL.
*
* For using Coin with software that can not be combined with the GNU
* GPL, and for taking advantage of the additional benefits of our
* support services, please contact Kongsberg Oil & Gas Technologies
* about acquiring a Coin Professional Edition License.
*
* See http://www.coin3d.org/ for more information.
*
* Kongsberg Oil & Gas Technologies, Bygdoy Alle 5, 0257 Oslo, NORWAY.
* http://www.sim.no/ sales@sim.no coin-support@coin3d.org
*
\**************************************************************************/
/*!
\class SoLight SoLight.h Inventor/nodes/SoLight.h
\brief The SoLight class is the base class for light emitting nodes.
\ingroup nodes
This node type is abstract and does not in itself provide any light
sources to the scene, you need to use one of its subclasses.
There are a few important things to know about light sources in
Coin. First of all, the more light sources you have in your scene,
the slower the rendering will be. The impact on rendering speed is
highly dependent on the graphics hardware and/or rendering subsystem
software implementation (i.e. how optimized an OpenGL you or your
users are running), but it could be severe.
Another issue which is important to know is that OpenGL rendering
engines usually have a fixed maximum number of available light
sources which can be present in the state at the same time. If you
reach the maximum number, further light sources will simply be
ignored. The maximum number of light sources for OpenGL rendering
can be found by using:
\code
#include <Inventor/elements/SoGLLightIdElement.h>
#include <Inventor/nodes/SoSubNodeP.h>
// ...[snip]...
int nrlights = SoGLLightIdElement::getMaxGLSources();
\endcode
If you are clever with how you use light sources, you can get away
with using a lot more lights in a scene graph than the max available
from the rendering system. This is because light sources are stacked
on the traversal state, just like other appearance data. So if you
put light sources under SoSeparator nodes, they will be popped off
and "forgotten" for the remaining geometry of the scene graph after
the subgraph below an SoSeparator has been traversed.
*/
#include <Inventor/nodes/SoLight.h>
#include <Inventor/actions/SoCallbackAction.h>
#include <Inventor/actions/SoGLRenderAction.h>
#include <Inventor/elements/SoGLLightIdElement.h>
#include <Inventor/elements/SoLightAttenuationElement.h>
#include <Inventor/elements/SoLightElement.h>
#include <Inventor/elements/SoModelMatrixElement.h>
#include <Inventor/elements/SoViewingMatrixElement.h>
#include "nodes/SoSubNodeP.h"
/*!
\var SoSFBool SoLight::on
Whether light source should be on or off. The on-flag defaults to \c
TRUE.
*/
/*!
\var SoSFFloat SoLight::intensity
Intensity of light source. This decides how much the light source
should affect the colors etc of the scene geometry. Valid range is
0.0 (none) to 1.0 (maximum). Default value is 1.0.
*/
/*!
\var SoSFColor SoLight::color
Color of light source. Default is an all-white light source.
*/
SO_NODE_ABSTRACT_SOURCE(SoLight);
/*!
Constructor.
*/
SoLight::SoLight(void)
{
SO_NODE_INTERNAL_CONSTRUCTOR(SoLight);
SO_NODE_ADD_FIELD(on, (TRUE));
SO_NODE_ADD_FIELD(intensity, (1.0f));
SO_NODE_ADD_FIELD(color, (SbColor(1.0f, 1.0f, 1.0f)));
}
/*!
Destructor.
*/
SoLight::~SoLight()
{
}
// Doc from superclass.
void
SoLight::initClass(void)
{
SO_NODE_INTERNAL_INIT_ABSTRACT_CLASS(SoLight, SO_FROM_INVENTOR_1);
SO_ENABLE(SoGLRenderAction, SoLightAttenuationElement);
SO_ENABLE(SoGLRenderAction, SoGLLightIdElement);
SO_ENABLE(SoGLRenderAction, SoLightElement);
SO_ENABLE(SoCallbackAction, SoLightAttenuationElement);
SO_ENABLE(SoCallbackAction, SoLightElement);
}
// Doc from superclass.
void
SoLight::callback(SoCallbackAction * action)
{
SoState * state = action->getState();
SoLightElement::add(state, this, (SoModelMatrixElement::get(state) *
SoViewingMatrixElement::get(state)));
}
|