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3Open Asset Import Library (assimp)
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42*/
43
44/** @file light.h
45 * @brief Defines the aiLight data structure
46 */
47
48#pragma once
49#ifndef AI_LIGHT_H_INC
50#define AI_LIGHT_H_INC
51
52#include "types.h"
53
54#ifdef __cplusplus
55extern "C" {
56#endif
57
58// ---------------------------------------------------------------------------
59/** Enumerates all supported types of light sources.
60 */
61enum aiLightSourceType
62{
63 aiLightSource_UNDEFINED = 0x0,
64
65 //! A directional light source has a well-defined direction
66 //! but is infinitely far away. That's quite a good
67 //! approximation for sun light.
68 aiLightSource_DIRECTIONAL = 0x1,
69
70 //! A point light source has a well-defined position
71 //! in space but no direction - it emits light in all
72 //! directions. A normal bulb is a point light.
73 aiLightSource_POINT = 0x2,
74
75 //! A spot light source emits light in a specific
76 //! angle. It has a position and a direction it is pointing to.
77 //! A good example for a spot light is a light spot in
78 //! sport arenas.
79 aiLightSource_SPOT = 0x3,
80
81 //! The generic light level of the world, including the bounces
82 //! of all other light sources.
83 //! Typically, there's at most one ambient light in a scene.
84 //! This light type doesn't have a valid position, direction, or
85 //! other properties, just a color.
86 aiLightSource_AMBIENT = 0x4,
87
88 //! An area light is a rectangle with predefined size that uniformly
89 //! emits light from one of its sides. The position is center of the
90 //! rectangle and direction is its normal vector.
91 aiLightSource_AREA = 0x5,
92
93 /** This value is not used. It is just there to force the
94 * compiler to map this enum to a 32 Bit integer.
95 */
96#ifndef SWIG
97 _aiLightSource_Force32Bit = INT_MAX
98#endif
99};
100
101// ---------------------------------------------------------------------------
102/** Helper structure to describe a light source.
103 *
104 * Assimp supports multiple sorts of light sources, including
105 * directional, point and spot lights. All of them are defined with just
106 * a single structure and distinguished by their parameters.
107 * Note - some file formats (such as 3DS, ASE) export a "target point" -
108 * the point a spot light is looking at (it can even be animated). Assimp
109 * writes the target point as a subnode of a spotlights's main node,
110 * called "<spotName>.Target". However, this is just additional information
111 * then, the transformation tracks of the main node make the
112 * spot light already point in the right direction.
113*/
114struct aiLight
115{
116 /** The name of the light source.
117 *
118 * There must be a node in the scenegraph with the same name.
119 * This node specifies the position of the light in the scene
120 * hierarchy and can be animated.
121 */
122 C_STRUCT aiString mName;
123
124 /** The type of the light source.
125 *
126 * aiLightSource_UNDEFINED is not a valid value for this member.
127 */
128 C_ENUM aiLightSourceType mType;
129
130 /** Position of the light source in space. Relative to the
131 * transformation of the node corresponding to the light.
132 *
133 * The position is undefined for directional lights.
134 */
135 C_STRUCT aiVector3D mPosition;
136
137 /** Direction of the light source in space. Relative to the
138 * transformation of the node corresponding to the light.
139 *
140 * The direction is undefined for point lights. The vector
141 * may be normalized, but it needn't.
142 */
143 C_STRUCT aiVector3D mDirection;
144
145 /** Up direction of the light source in space. Relative to the
146 * transformation of the node corresponding to the light.
147 *
148 * The direction is undefined for point lights. The vector
149 * may be normalized, but it needn't.
150 */
151 C_STRUCT aiVector3D mUp;
152
153 /** Constant light attenuation factor.
154 *
155 * The intensity of the light source at a given distance 'd' from
156 * the light's position is
157 * @code
158 * Atten = 1/( att0 + att1 * d + att2 * d*d)
159 * @endcode
160 * This member corresponds to the att0 variable in the equation.
161 * Naturally undefined for directional lights.
162 */
163 float mAttenuationConstant;
164
165 /** Linear light attenuation factor.
166 *
167 * The intensity of the light source at a given distance 'd' from
168 * the light's position is
169 * @code
170 * Atten = 1/( att0 + att1 * d + att2 * d*d)
171 * @endcode
172 * This member corresponds to the att1 variable in the equation.
173 * Naturally undefined for directional lights.
174 */
175 float mAttenuationLinear;
176
177 /** Quadratic light attenuation factor.
178 *
179 * The intensity of the light source at a given distance 'd' from
180 * the light's position is
181 * @code
182 * Atten = 1/( att0 + att1 * d + att2 * d*d)
183 * @endcode
184 * This member corresponds to the att2 variable in the equation.
185 * Naturally undefined for directional lights.
186 */
187 float mAttenuationQuadratic;
188
189 /** Diffuse color of the light source
190 *
191 * The diffuse light color is multiplied with the diffuse
192 * material color to obtain the final color that contributes
193 * to the diffuse shading term.
194 */
195 C_STRUCT aiColor3D mColorDiffuse;
196
197 /** Specular color of the light source
198 *
199 * The specular light color is multiplied with the specular
200 * material color to obtain the final color that contributes
201 * to the specular shading term.
202 */
203 C_STRUCT aiColor3D mColorSpecular;
204
205 /** Ambient color of the light source
206 *
207 * The ambient light color is multiplied with the ambient
208 * material color to obtain the final color that contributes
209 * to the ambient shading term. Most renderers will ignore
210 * this value it, is just a remaining of the fixed-function pipeline
211 * that is still supported by quite many file formats.
212 */
213 C_STRUCT aiColor3D mColorAmbient;
214
215 /** Inner angle of a spot light's light cone.
216 *
217 * The spot light has maximum influence on objects inside this
218 * angle. The angle is given in radians. It is 2PI for point
219 * lights and undefined for directional lights.
220 */
221 float mAngleInnerCone;
222
223 /** Outer angle of a spot light's light cone.
224 *
225 * The spot light does not affect objects outside this angle.
226 * The angle is given in radians. It is 2PI for point lights and
227 * undefined for directional lights. The outer angle must be
228 * greater than or equal to the inner angle.
229 * It is assumed that the application uses a smooth
230 * interpolation between the inner and the outer cone of the
231 * spot light.
232 */
233 float mAngleOuterCone;
234
235 /** Size of area light source. */
236 C_STRUCT aiVector2D mSize;
237
238#ifdef __cplusplus
239
240 aiLight() AI_NO_EXCEPT
241 : mType (aiLightSource_UNDEFINED)
242 , mAttenuationConstant (0.f)
243 , mAttenuationLinear (1.f)
244 , mAttenuationQuadratic (0.f)
245 , mAngleInnerCone ((float)AI_MATH_TWO_PI)
246 , mAngleOuterCone ((float)AI_MATH_TWO_PI)
247 , mSize (0.f, 0.f)
248 {
249 }
250
251#endif
252};
253
254#ifdef __cplusplus
255}
256#endif
257
258
259#endif // !! AI_LIGHT_H_INC
260

source code of qt3d/src/3rdparty/assimp/src/include/assimp/light.h