SoPathTracerAreaLight

InventorModule

author	MeVis Medical Solutions AG
package	MeVisLab/Standard
dll	SoPathTracer
definition	SoPathTracer.def

Purpose

The SoPathTracerAreaLight module provides a physically based area light that illuminates the scene of a SoPathTracer. The lights can be rectangular or disc-shaped and possess an area, color, and intensity. They can be positioned using spherical coordinates around the bounding box of the renderer, or they can be positioned in world or camera space.

Since the light is physically modeled, it exhibits a quadratic falloff. By default, the light intensity is adjusted based on the distance of the light to the center of the bounding box, ensuring that the same intensity reaches the center.

Multiple area lights can be used; however, performance will noticeably decrease when using too many lights.

Windows

Default Panel

Parameter Fields

Field Index

Altitude: Float	Intensity: Float
Attach light to camera: Bool	Mode: Enum
Azimuth: Float	Orientation: Rotation
Color: Color	Position: Vector3
Diameter: Float	Render source: Bool
Distance: Float	Scale Mode: Enum
Enabled: Bool	Type: Enum
Height: Float

Visible Fields

Enabled

name: enabled, type: Bool, default: TRUE

If checked, the light is enabled.

Render source

name: renderSource, type: Bool, default: FALSE

If checked, the light source itself is rendered in the scene (only for debugging)

Color

name: color, type: Color, default: 1 1 1

Sets the color of the light.

Intensity

name: intensity, type: Float, default: 5, minimum: 0, maximum: 20

Sets the intensity of the light.

Diameter

name: width, type: Float, default: 0.5, minimum: 0.01, maximum: 5

Sets the diameter of the disc relative to the bounding box of the volume.

Height

name: height, type: Float, default: 0.5, minimum: 0.01, maximum: 5

Sets the height of the rectangle relative to the bounding box of the volume.

Altitude

name: theta, type: Float, default: 180

Sets the spherical coordinate theta.

Azimuth

name: phi, type: Float, default: 45

Sets the spherical coordinate phi.

Distance

name: distance, type: Float, default: 3.5, minimum: 0, maximum: 10

Sets the distance of the light to the bounding box of the scene relative to the diameter of the bounding box.

Attach light to camera

name: attachToCamera, type: Bool, default: FALSE

If checked, the light is attached to the camera space rather than world space.

Position

name: position, type: Vector3, default: 0 0 0

Sets the position of the light (in world or camera space), when Mode is PositionAndOrientation.

Orientation

name: orientation, type: Rotation, default: 0 0 1 0

Sets the orientation of the light (in world or camera space), when Mode is PositionAndDirection.

Type

name: type, type: Enum, default: AreaLight_Rectangle

Defines the shape of the light.

Values:

Title	Name	Description
​Disc	​AreaLight_Disc	​Disc
​Rectangle	​AreaLight_Rectangle	​Rectangle

Mode

name: mode, type: Enum, default: DistanceAndAngles

Defines the positioning mode.

Values:

Title	Name	Description
​Position And Orientation	​PositionAndOrientation	​Light is positioned via position and orientation, in world or camera space depending on Attach light to camera.
​Distance And Angles	​DistanceAndAngles	​Light is positioned around the bounding box of the scene in the specified distance and with the specified spherical coordinates that are specified in angles.

Scale Mode

name: scaleMode, type: Enum, default: ScaleToBoundingSphere

Defines the scaling of the light parameters.

Values:

Title	Name	Description
​Scale To Bounding Sphere	​ScaleToBoundingSphere	​Scale the light intensity and distance by the diameter of the bounding box.
​Scaling Off	​ScalingOff	​No scaling.