Specifying a Sun Setting

You can specify a sun setting for solar studies, walkthroughs, and rendered images either by using the Sun Settings dialog (as described in this topic) or, in many cases, by using the sun path’s on-screen controls.

1. Open a 2D or 3D view that supports the display of shadows.
2. To turn on shadows, on the View Control Bar, click Shadows On/OffShadows On.
3. Click Manage tabSettings panelAdditional Settings drop-down Sun Settings.

   Or, on the View Control Bar, click Sun Path Off/OnSun Settings.

   Note: You can also access the Sun Settings dialog from the Rendering dialog or the Graphic Display Options dialog.
4. In the Sun Settings dialog, under Solar Study, select a mode:
   • To define the sun setting based on a specified geographic location, select Still, Single Day, or Multi-Day.
   • To define the sun setting based on azimuth and altitude, select Lighting.
5. Under Presets, select one of the predefined sun settings (such as a solstice) and click OK, or select the In-session preset and complete the remaining steps in this procedure to define your own sun setting.
6. Specify a sun setting for the specified mode:

   For a Still, Single Day, or Multi-Day study

   1. For Location, verify that the correct project location is displayed.

      To change the location, click (Browse), and specify the project location either by searching on the street address or longitude and latitude, or by selecting the nearest major city from the Default City List.

   2. For Date, enter a date for the study.

      For a Multi-Day study, enter both a start date and an end date.

   3. For Time, enter a time for the study.

      For Single Day and Multi-Day studies, enter both a start time and an end time, or select Sunrise to Sunset.

      Tip: For a Multi-Day study, to see the sun and shadow patterns for the same point in time over a range of days, enter the same start time and end time. You can also accomplish this by specifying the Time Interval as One day.

   For a Lighting study

   1. Enter values for Azimuth and Altitude.

      Azimuth is the bearing angle from True North, measured in degrees. Azimuth angles range from 0 degrees (north) through 90 (east), 180 (south), 270 (west), and up to 360 (north again).

      Altitude is the vertical angle between the horizon and the sun, measured from the horizon. Altitude angles range from 0 (on the horizon) up to 90 degrees (at the zenith).

   2. To orient the sun to match the orientation of the view, select Relative to View. Or, to orient the sun to match the orientation of the model, clear Relative to View.
7. To cast shadows on the ground plane, select Ground Plane at Level, and select the level at which you want the shadows to display.

   When you select Ground Plane at Level, the software casts shadows on the specified level in 2D and 3D shaded views. When you clear Ground Plane at Level, the software casts shadows on the toposurface, if one exists.

   Note: The ground plane is not used in rendered views. To cast shadows in rendered views, model a ground plane in the project.
8. To test the sun setting in the active view, click Apply.
   Note: For Single Day and Multi-Day studies, the sun is placed at the first frame of the animation. The shadows you see in the view are cast from this sun position.
9. Click OK when done.
10. To save the current sun setting as a preset, see Work with Sun Setting Presets.