Use Point Lights

A point light radiates light in all directions from its location.

Point Lights

A point light radiates light in all directions from its location. A point light does not target an object. Use point lights for general lighting effects. You can create a point light by entering the POINTLIGHT command or by selecting a point light from the Lights panel on the ribbon.

You create a target point light with the TARGETPOINT command. The difference between the target point light and a point light is the additional target properties that are available. A target light can be pointed to an object. A target point light can also be created from a point light by changing the target property of the point light from No to Yes.

In the standard lighting workflow, you can set a point light manually so its intensity diminishes with respect to distance either linearly, according to the inverse square of the distance, or not at all. By default, the attenuation is set to None.

Point Lights in Photometric Workflow

A free point light can have photometric distribution properties. The attenuation for a photometric point light is always set to inverse square.

When the LIGHTINGUNITS system variable is set to 1 (American units) or 2 (International SI units) for photometric lighting, additional properties are available for a point light. On the Properties palette, photometric properties are

Lamp Intensity. Specifies the inherent brightness of the light. Specifies the intensity, flux or illuminance of the lamp.
Resulting Intensity. Gives the final brightness of the light. (Product of lamp intensity and intensity factor. Read-only.)
Lamp Color. Specifies the inherent color of the light in Kelvin temperature or standard.
Resulting Color. Gives the final color of the light. This is determined by a combination of the lamp color and the filter color. (Product of lamp color and filter color. Read-only.)

NoteWhen the drawing lighting units are photometric, the attenuation type property becomes disabled. Photometric lights have fixed, inverse-square attenuation.

The additional information about these properties are available under Lighting Properties. The following image is an example of a photometric point light and lighting properties palette with the photometric properties outlined:

Procedure

To create a point light in standard lighting workflow

To create a point light in photometric workflow and change photometric properties

To create a target point light in standard lighting workflow

To create a target point light from a point light

Click Render tab Lights panel Lighting Units drop-down Generic Lighing Units.
No lighting units are used and standard (generic) lighting is enabled.

NoteAlternatively, you can enter lightingunits at the Command prompt and set the value to 0 for standard (generic) lighting.
Click Render tab Lights panel Create Light drop-down Point.
Click in the drawing to specify a location for the light.
At the Command prompt, enter n and enter a name. This name will appear in the properties and in the Lights in Model window (LIGHTLIST).
You can continue to specify properties by entering options, or you can exit and set properties interactively. When you use the interactive method, you can see the results of your changes as you work.
Press Enter twice to exit the command.
Right-click the light and click Properties on the Lighting Properties palette. Change the Targeted property to Yes.
Additional target properties become available: Target X, Target Y, and Target Z.

NoteWhen changing a point light to target light, the name of the light remains the same. If it still says point light, you might want to change the name to target light.

To create a point light tool

Quick Reference

Commands

System Variables

DEFAULTLIGHTING

Turns on and off default lighting in place of other lighting.

DEFAULTLIGHTINGTYPE

Specifies the type of default lighting, old or new.

LIGHTGLYPHDISPLAY

Turns on and off the display of light glyphs.

LIGHTINGUNITS

Controls whether generic or photometric lights are used, and specifies the lighting units for the drawing.

LIGHTSINBLOCKS

Controls whether lights contained in blocks are used when rendering.

LINEARBRIGHTNESS

Controls the brightness level of the viewport when using default lighting or generic lights.

LINEARCONTRAST

Controls the contrast level of the viewport when using default lighting or generic lights.

LOGEXPBRIGHTNESS

Controls the brightness level of the viewport when using photometric lighting.

LOGEXPCONTRAST

Controls the contrast level of the viewport when using photometric lighting.

LOGEXPDAYLIGHT

Controls if the exterior daylight flag is enabled when using photometric lighting.

LOGEXPMIDTONES

Controls the mid tones level of the viewport when using photometric lighting.

RENDERUSERLIGHTS

Controls whether to override the setting for viewport lighting during rendering.