A light source is a specific Object data type that allows you to control the settings of various, most commonly used real-time lights. Out of the box, a light source object can handle the following type of lights: Ambient, Sun (directional), Lamp (point light) and Spots (directional cone or square light).

Once you have placed them into your scene it is up to you to send which information to your Shader to compute lighting. A common technique to avoid extra lighting computations is to use a Sensor that returns the nearest light sources relative to your main Camera object. Using the Volume information of the Sensor you can quickly determine which light(s) data needs to be send over to your lighting Shader.

See Also

Object, Shader, Sensor, Camera, Volume

Static Variables

Name	Description
`object`	Parent Object where the LightSource data information is stored.
Declaration Object *object
`position`	The position of the LightSource in eye space.
Declaration vec3 position
`direction`	The direction vector of the LightSource in eye space.
Declaration vec3 direction

Variables

Name	Description
`distance`	The maximum distance the light rays can reach.
Declaration float distance Range 0.01 to inf.
`intensity`	Controls the intensity of the LightSource.
Declaration float intensity Range 0.0 to inf. Remarks This value commonly used as a multiplier for the color of the light source.
`falloff_angle`	Angle in degree describing the field of view of the spot light.
Declaration float falloff_angle Range 0.01 to 180.0
`falloff_exponent`	Blending factor to apply on the spot which basically control the softness of the light emitted by the spot.
Declaration float falloff_exponent Range 0.0 to 1.0
`falloff_clamp`	Determine whether or not the attenuation should be clamped based on the distance parameter of the active light source.
Declaration bool falloff_clamp
`constant_attenuation`	Constant attenuation factor.
Declaration float constant_attenuation Range 0.0 to 1.0
`linear_attenuation`	Linear attenuation factor.
Declaration float linear_attenuation Range 0.0 to 1.0
`quadratic_attenuation`	Quadratic attenuation factor.
Declaration float quadratic_attenuation Range 0.0 to 1.0
`light_type`	Active LightType used by the LightSource.
Declaration LightType light_type
`falloff`	The current FalloffType the current LightSource is using.
Declaration FalloffType falloff
`color`	The color of the LightSource which can be either set in LDR or HDR.
Declaration vec4 color Remarks The `.w` component of the color vector is used internally by the system to store the active LightType of the light source (like this a single vector can be passed down to your Shader).
`square`	Controls wether a not a spot light should be round or square.
Declaration bool square
`square_size`	The size of the square spot light on the `X` and `Y` axis.
Declaration vec2 square_size Range 0.0 to 5.0

Functions

Name	Description
`SetSphericalHarmonics`	Create and append a new RenderLayer to the active Scene.
Declaration bool SetSphericalHarmonics( const unsigned char index, const vec3 component ) Parameters `index`: Index of the 2nd degree spherical harmonics value to update. `component`: Tri-dimensional vector holding the value of the component to update. Return Value `true` if the index provided is within the range of `0` to `8`; else return `false`.
`GetSphericalHarmonics`	Retrieve a single vector assigned to a specific component index.
Declaration vec3 GetSphericalHarmonics( const unsigned char index ) Parameters `index`: Index of the 2nd degree spherical harmonics value to retrieve. Return Value On sucess return the vector associated to the component `index` else return an empty vector.

LightType

Commonly used light type for real-time.

kWorld: Ambient light.
kSun: Uni-directional light source.
kLamp: Omnidirectional light source.
kSpot: Cone of light pointing at a specific direction.

FalloffType

Most common falloff attenuation models used to control how the light intensity decay with distance.

kNoAttenuation: Does not attenuate with distance.
kInverseLinear: Attenuates the intensity linearly, scaled by the distance value.
kInverseSquare: Attenuates the intensity according to inverse square law, scaled by the distance value.
kLinearQuadratic: Linear quadratic light source attenuation equation.
kQuadratic: Quadratic light source attenuation.