Lighting Properties (Properties Palette)

Available properties depend on the lighting units (standard or photometric) and lighting type (Spotlight, Pointlight, or Weblight). Right-click on a light and choose Properties to display the Lighting category of the Properties palette.

List of Options

The following options are displayed.

General Properties

The following settings are available:

Name

Specifies the name of the light.

Type (Light Distribution)

Specifies the type of light. Determines the distribution of light from the . The type of lighting can be changed after the light has been added to the drawings.

• Spotlight - Default value for Spotlight and Freespot lights.
• Point - Default for Pointlight and Targetpoint lights.
• Web - Default for Weblight and Freeweb lights.

On/Off Status

Indicates whether the light is on or off.

Hotspot Angle (Spotlight and Freespot only)

Specifies the angle of the brightest cone of light. Settings can be calculated by using the QuickCalc Calculator.

Falloff Angle (Spotlight and Freespot only)

Specifies the outer extremity of the light, where it meets the darkness.

Intensity Factor

Magnifies the effect of the skylight.

Filter Color

Specifies the secondary color of the light. Represents the color of a physical filter over the lamp. Default color is white.

When lighting is set to photometric units this represents a secondary color filter on the light. When lighting is set to generic lighting this represents the total color of the light.

Plot Glyph

Allows the ability to plot the drawing with the glyphs on.

Photometric

The following settings are available:

Note: Photometric related properties are available when the LIGHTINGUNITS system variable is set to 1 or 2.

Lamp Intensity

Specifies the inherent brightness of the light. Specifies the intensity, flux, or illuminance of the lamp. Default units are candela.

Displays the Lamp Intensity dialog box, where units can be modified.

Resulting Intensity

Reports the final brightness of the light. This is determined by the product of the Lamp Intensity and the Intensity factor. This value is calculated in the Lamp Intensity Dialog box. (Read-only)

Lamp Color

Specifies the inherent color of the light in Kelvin temperature or standard. Displays the Lamp Color dialog box.

Resulting Color

Reports the final color of the light. This is determined by a combination of the Lamp Color and the Filter Color. (Read-only)

Photometric Web

The following settings are available for Web and Freeweb lights:

Web File

Specifies the data file describing the intensity distribution of the light.

Web Preview

Displays a 2D slice through goniometric data.

Web Offsets

Under the Web offsets panel, the following settings are available under the Weblight and Freeweb types of lights:

Rotation X

Specifies a rotational offset of the web about the optical X axis.

Rotation Y

Specifies a rotational offset of the web about the optical Y axis.

Rotation Z

Specifies a rotational offset of the web about the optical Z axis.

Geometry

Under the Geometry panel, the following settings are available:

Position X

Specifies the X coordinate position of the light.

Position Y

Specifies the Y coordinate position of the light.

Position Z

Specifies the Z coordinate position of the light.

Target X

Specifies the X coordinate target position of the light. (Spotlight, Targetpoint, and Weblight only)

Target Y

Specifies the Y coordinate target position of the light. (Spotlight, Targetpoint, and Weblight only)

Target Z

Specifies the Z coordinate target position of the light. (Spotlight, Targetpoint, and Weblight only)

Targeted

Specifies if the light displays a target grip for orienting the light. Disabled is the default for Freespot, Pointlight, and Freeweb. Enabled is the default for Spotlight, Targetpoint, and Weblight.

Attenuation

In the real world, the intensity of light diminishes over distance. Objects far from the light source appear darker than objects near the source. This effect is known as attenuation. Attenuation is available under standard lighting workflow only.

Note: Starting with AutoCAD 2016-based products, all lighting is calculated using inverse square attenuation. The attenuation related options are maintained for backwards compatibility with AutoCAD 2015-based products and earlier releases.

Under the Attenuation panel the following property settings are available:

Type

Controls how light diminishes over distance. The farther away an object is from a spotlight, the darker the object appears. Attenuation is also known as decay.

• Inverse Linear (Standard lights only). Sets attenuation to be the inverse of the linear distance from the light. For example, at a distance of 2 units, light is half as strong as at the point light; at a distance of 4 units, light is one quarter as strong. The default value for inverse linear is half the maximum intensity.
• Inverse Square (Photometric lights). Sets attenuation to be the inverse of the square of the distance from the light. For example, at a distance of 2 units, light is one quarter as strong as at the spotlight; at a distance of 4 units, light is one sixteenth as strong.
• None (Standard lights only). Sets no attenuation. Objects far from the point light are as bright as objects close to the light.

Use Limits

Specifies whether to use limits. The default is No. (Standard lights only)

Start Limit Offset

Specifies the point where light starts as an offset from the center of the light. The default is 1. (Standard lights only)

End Limit Offset

Specifies the point where light ends as an offset from the center of the light. No light is cast beyond this point. (Standard lights only)