assimp/include/assimp/light.h

259 lines
8.9 KiB
C

/*
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Open Asset Import Library (assimp)
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*/
/** @file light.h
* @brief Defines the aiLight data structure
*/
#pragma once
#ifndef AI_LIGHT_H_INC
#define AI_LIGHT_H_INC
#ifdef __GNUC__
# pragma GCC system_header
#endif
#include <assimp/types.h>
#ifdef __cplusplus
extern "C" {
#endif
// ---------------------------------------------------------------------------
/** Enumerates all supported types of light sources.
*/
enum aiLightSourceType {
aiLightSource_UNDEFINED = 0x0,
//! A directional light source has a well-defined direction
//! but is infinitely far away. That's quite a good
//! approximation for sun light.
aiLightSource_DIRECTIONAL = 0x1,
//! A point light source has a well-defined position
//! in space but no direction - it emits light in all
//! directions. A normal bulb is a point light.
aiLightSource_POINT = 0x2,
//! A spot light source emits light in a specific
//! angle. It has a position and a direction it is pointing to.
//! A good example for a spot light is a light spot in
//! sport arenas.
aiLightSource_SPOT = 0x3,
//! The generic light level of the world, including the bounces
//! of all other light sources.
//! Typically, there's at most one ambient light in a scene.
//! This light type doesn't have a valid position, direction, or
//! other properties, just a color.
aiLightSource_AMBIENT = 0x4,
//! An area light is a rectangle with predefined size that uniformly
//! emits light from one of its sides. The position is center of the
//! rectangle and direction is its normal vector.
aiLightSource_AREA = 0x5,
/** This value is not used. It is just there to force the
* compiler to map this enum to a 32 Bit integer.
*/
#ifndef SWIG
_aiLightSource_Force32Bit = INT_MAX
#endif
};
// ---------------------------------------------------------------------------
/** Helper structure to describe a light source.
*
* Assimp supports multiple sorts of light sources, including
* directional, point and spot lights. All of them are defined with just
* a single structure and distinguished by their parameters.
* Note - some file formats (such as 3DS, ASE) export a "target point" -
* the point a spot light is looking at (it can even be animated). Assimp
* writes the target point as a sub-node of a spot-lights's main node,
* called "<spotName>.Target". However, this is just additional information
* then, the transformation tracks of the main node make the
* spot light already point in the right direction.
*/
struct aiLight {
/** The name of the light source.
*
* There must be a node in the scene-graph with the same name.
* This node specifies the position of the light in the scene
* hierarchy and can be animated.
*/
C_STRUCT aiString mName;
/** The type of the light source.
*
* aiLightSource_UNDEFINED is not a valid value for this member.
*/
C_ENUM aiLightSourceType mType;
/** Position of the light source in space. Relative to the
* transformation of the node corresponding to the light.
*
* The position is undefined for directional lights.
*/
C_STRUCT aiVector3D mPosition;
/** Direction of the light source in space. Relative to the
* transformation of the node corresponding to the light.
*
* The direction is undefined for point lights. The vector
* may be normalized, but it needn't.
*/
C_STRUCT aiVector3D mDirection;
/** Up direction of the light source in space. Relative to the
* transformation of the node corresponding to the light.
*
* The direction is undefined for point lights. The vector
* may be normalized, but it needn't.
*/
C_STRUCT aiVector3D mUp;
/** Constant light attenuation factor.
*
* The intensity of the light source at a given distance 'd' from
* the light's position is
* @code
* Atten = 1/( att0 + att1 * d + att2 * d*d)
* @endcode
* This member corresponds to the att0 variable in the equation.
* Naturally undefined for directional lights.
*/
float mAttenuationConstant;
/** Linear light attenuation factor.
*
* The intensity of the light source at a given distance 'd' from
* the light's position is
* @code
* Atten = 1/( att0 + att1 * d + att2 * d*d)
* @endcode
* This member corresponds to the att1 variable in the equation.
* Naturally undefined for directional lights.
*/
float mAttenuationLinear;
/** Quadratic light attenuation factor.
*
* The intensity of the light source at a given distance 'd' from
* the light's position is
* @code
* Atten = 1/( att0 + att1 * d + att2 * d*d)
* @endcode
* This member corresponds to the att2 variable in the equation.
* Naturally undefined for directional lights.
*/
float mAttenuationQuadratic;
/** Diffuse color of the light source
*
* The diffuse light color is multiplied with the diffuse
* material color to obtain the final color that contributes
* to the diffuse shading term.
*/
C_STRUCT aiColor3D mColorDiffuse;
/** Specular color of the light source
*
* The specular light color is multiplied with the specular
* material color to obtain the final color that contributes
* to the specular shading term.
*/
C_STRUCT aiColor3D mColorSpecular;
/** Ambient color of the light source
*
* The ambient light color is multiplied with the ambient
* material color to obtain the final color that contributes
* to the ambient shading term. Most renderers will ignore
* this value it, is just a remaining of the fixed-function pipeline
* that is still supported by quite many file formats.
*/
C_STRUCT aiColor3D mColorAmbient;
/** Inner angle of a spot light's light cone.
*
* The spot light has maximum influence on objects inside this
* angle. The angle is given in radians. It is 2PI for point
* lights and undefined for directional lights.
*/
float mAngleInnerCone;
/** Outer angle of a spot light's light cone.
*
* The spot light does not affect objects outside this angle.
* The angle is given in radians. It is 2PI for point lights and
* undefined for directional lights. The outer angle must be
* greater than or equal to the inner angle.
* It is assumed that the application uses a smooth
* interpolation between the inner and the outer cone of the
* spot light.
*/
float mAngleOuterCone;
/** Size of area light source. */
C_STRUCT aiVector2D mSize;
#ifdef __cplusplus
aiLight() AI_NO_EXCEPT
: mType (aiLightSource_UNDEFINED)
, mAttenuationConstant (0.f)
, mAttenuationLinear (1.f)
, mAttenuationQuadratic (0.f)
, mAngleInnerCone ((float)AI_MATH_TWO_PI)
, mAngleOuterCone ((float)AI_MATH_TWO_PI)
, mSize (0.f, 0.f)
{
}
#endif
};
#ifdef __cplusplus
}
#endif
#endif // !! AI_LIGHT_H_INC