Program help

Spot Light

The spot light is a light source which creates a cone of light similar to that of a flashlight. It can be used in many ways, as demonstrated in the following images.




The following is how to insert a spot light:

1.It is best to switch to the appropriate 2D projection, depending on the desired direction of the cone.

2.Go to the Lighting menu in the Room group, Start tab, and select Spot Light.

3.Use one click to set the origin for the light source.

4.Moving the mouse or entering figures on the keyboard enables you to determine the orientation and size of the graphic representation of the spot light.

5.Clicking again or confirming with the Enter key ends the creation stage.


There are a number of properties which can be edited for a spot light. The image below shows a spot light selected in the Perspective projection together with its properties which are listed in the Properties dialog.




Can be changed by means of


A Spotlight can either be transformed to a Point light, a Directional light or an Area light

Properties Editor

Color Temperature

The Color Temperature defines whether a light source emits a warm or a cold light. It is specified in Kelvin (K).

Lower K values make the light appear warm, higher values make the light appear cold.


Properties Editor


Setting the color of the light

Properties Editor


The figure is given in candelas (cd). 1 cd is approximately the intensity of the light from one candle. The intensity of a  spot light diminishes exponentially in relation to the distance from the origin.

Properties Editor

Opening angle

The opening angle sets the angle of the cone of light. It determines the maximum circle on which the light will fall (see image below).

Properties Editor, circle (see image)

Hotspot angle

Within the opening angle it is possible to set another cone of light using the hotspot angle. The effect of different hotspot angles is shown in the image below.

Properties Editor

Realtime Shadows

Enabling or disabling the calculation of shadows for realtime rendering

Properties Editor

Light enabled

This switches the light source on and off

Properties Editor


This is relevant for photorealistic rendering. The larger the source of light, the softer the shadow in the image rendered.

Properties Editor


This is whether shadows should be calculated during the rendering process or not

Properties Editor


It is possible to give a name to any of the light sources

Properties Editor


The target interactor will set the direction of the spot light.

Interactor (see image)


The origin interactor allows the position of the origin to be changed

Interactor (see image)


The spot light can be moved

Section of line (see image)