A manual page a day... Click here to see the manual table of contents.
Toolbar: Render > Lights (
Menu: View > Render > Light.
Keyboard: LIGHTING.
Alias: LIGHT.
The Lighting command activates the Lighting dialog box which allows you to specify how your drawing or scene is lit. You can control placement of the lights, light color, and light intensity. The Lighting dialog box, illustrated below, includes four buttons in the upper left corner of the window that allow you to select a preset lighting configuration. To the right of those buttons is a list of all of the lights currently defined in the drawing and buttons that allow you to add or delete from the list of lights. The change the characteristics of a particular light in the drawing, you first click on the name of the light in the light list. In the upper right corner of the window, the name of the selected light will be shown, as well as the color of the light and the light type.
Various other light parameters will be shown in the middle section of the window depending on the particular light type. Three types of lights are available to use in your drawing, Ambient light, Point lights, and Distant lights. An Ambient light illuminates the entire scene evenly (depending on the Ambient component of the Material finish). It does not cast shadows or change with viewing angle. A Point light represents light eminating from a single point in the drawing. Shadows will be cast by surfaces in the drawing and you will see highlights where the light reflects off of the surfaces. Point lights can also have a size or diameter to them so that they cast soft shadows. A Distant light represents a light from a large distance away from the surfaces in the drawing (e.g. the sun). All of the light rays are essentially parallel to each other so the shadows cast by the light have sharp edges.
The quickest way to specify a lighting configuration is to select one of the several preset light configurations provided including "Eye Light," "Side Light," "Sun Light," and "Back Light". All of these options add a small amount of ambient light and then a single point light. The Eye Light places the point light at the eye position for the scene. The Side Light option adds the point light at the upper right side of the scene. The Sun Light option adds a slightly yellowish light at a fixed point in the drawing coordinate system. The Back Light option adds the light behind and above the scene. Examples are shown below of the preset lighting on an example sphere.
![]() | ![]() |
Eye Light | Side Light |
![]() | ![]() |
Sun Light | Back Light |
In addition to these preset lighting configurations, you can add individual lights by clicking on the "Add" button to the right of the list. You can delete lights by first clicking on the light in the list and then clicking on the "Delete" button to the right of the list. When you click on a light in the list it becomes selected and the parameters for that light are shown in the lower part of the window. Once you have selected the light of interest you can modify its parameters using the controls in the lower part of the window.
Lighting settings are stored in the drawing.
Control | Description |
---|---|
Name | The name field is an arbitrary name you can specify for the light to identify it in the Lights list at the top. |
Color | Clicking on the button in the color box will bring up a color selection dialog window that will allow you to specify the color for the light. |
Intensity | The light intensity is specified using this slider that ranges from 0 to 200. 100 is full intensity and 0 is completely dark. This allows you to adjust the brightness of the scene. Values above 100 will produce a brighter scene, but may oversaturate some areas. |
Control | Description |
---|---|
Name | The name field is an arbitrary name you can specify for the light to identify it in the Lights list at the top. |
Coordinate System | Point lights can be positioned anywhere in the scene either relative to the viewer or relative to the scene itself. If View is selected, the light is positioned relative to the viewer and as the view is modified by rotating or panning the drawing, then the light position will move as well. If World coordinates are selected, then the light will be placed at a fixed position relative to the drawing itself and the azimuth, elevation, and distance parameters are relative to the drawing origin (0, 0, 0). If XYZ coordinates are selected, then again the light will be placed at a fixed position relative to the drawing and you can enter the light X, Y, and Z coordinates directly. Lights placed in either the World or XYZ coordinate systems will not change position as you zoom or pan the drawing. |
Color | Clicking on the button in the color box will bring up a color selection dialog window that will allow you to specify the color for the light. |
Intensity | The light intensity is specified using this slider that ranges from 0 to 200. 100 is full intensity and 0 is completely dark. This allows you to adjust the brightness of the scene. Values above 100 will produce a brighter scene, but may oversaturate some areas. |
Diameter | The light diameter is specified using this slider that ranges from 0 to 1,000 drawing units. Larger diameters will produce softer edged shadows. A diameter of zero will produce a hard edged shadow. |
Azimut | The azimuth slider allows you to position the light in the azimuthal direction. This is best envisioned as a compass heading. When working in World coordinates, the azimuth is measured by standing at the scene origin, with the compass N heading pointed in the +Y direction. The direction to the light is then read from the compass. For example, an azimuth setting of 90 deg would be in the easterly or +X direction. When working in View coordinates, the azimuth is measured by standing at the view center point with the compass N heading pointing at the eye position. An azimuth setting of 90 deg would then be to the viewer's left. |
Distance | This is the distance in drawing units to the light from the view center point (in View coordinates) or from the drawing origin (when using World coordinates). |
Elevation | This is the vertical angle between the horizon and the light. In World coordinates, this is measured from the X-Y plane through the origin to the light. In View coordinates, the horizon plane is the plane normal (perpendicular) to the view "up" direction. An elevation value of 0 is on the horizon and an elevation value of 90 degrees is straight up. |
Light Coordinates | If the XYZ Coordinate system is selected, then lights can be placed using their X, Y, and Z coordinates directly. Text entry boxes will be displayed for each of the three coordinates. |
Control | Description |
---|---|
Name | The name field is an arbitrary name you can specify for the light to identify it in the Lights list at the top. |
Color | Clicking on the button in the color box will bring up a color selection dialog window that will allow you to specify the color for the light. |
Intensity | The light intensity is specified using this slider that ranges from 0 to 200. 100 is full intensity and 0 is completely dark. This allows you to adjust the brightness of the scene. Values above 100 will produce a brighter scene, but may oversaturate some areas. |
Azimut | The azimuth slider allows you to position the light in the azimuthal direction. This is best envisioned as a compass heading. The azimuth is measured by standing at the drawing origin, with the compass N heading pointed in the +Y direction. The direction to the light is then read from the compass. For example, an azimuth setting of 90 deg would be in the easterly or +X direction. |
Elevation | This is the vertical angle between the horizon and the light. This is measured from the X-Y plane through the origin to the light. An elevation value of 0 is on the horizon and an elevation value of 90 degrees is straight up. |
Date | This is the date at which the sun position will be calculated. The sun position varies based on the day of year and also to a lesser extent the particular year. |
Time | This is the local time of day in the timezone specified on the Site Location dialog. Note that daylight savings time is not automatically included so standard times should be used. |
Calculate Azimuth and Elevation | This button will cause the sun's azimuth and elevation to be calculated at the specified time and date. |
Edit Site Position | This button will show the Site Location dialog to allow you to adjust the site position (latitude and longitude), site time zone, and site orienation (relative to true north). |