Shadow study determines how and where shadows are cast during different times of the day for a proposed project or existing site. It determines the position of the sun relative to the object throughout the day and then positions the shadow of the object accordingly. Shadow study is a valuable aspect of project planning particularly where projects are sunlight dependent, or the position of shadows is critical. For example, shadow studies are important in the planning of solar projects or when a high-rise development is being proposed. In Autodesk 3ds Max, you can perform shadow studies by creating a daylight system and animating the sun object to simulate the movement of the sun during the day at a given location on earth.
Sun Positioner
The daylight system in 3ds Max is created by using the Sun Positioner system, which creates a light system providing realistic sunlight with a full sky environment. The following steps show you how to create a Sun Positioner:
1. In the Create panel (
), click 
(Lights). In the Object Type rollout, click Sun Positioner, as shown in the figure below.
2. The Sun Positioner enables you to create a compass rose and a light source that mimics the sun. Creating a sun positioner is a three click process:
- The first click sets the location and size of the compass rose. Click and drag to set the size of the compass rose in the viewport, as shown in the figure below.
- The second click sets the orientation of the sun by specifying the cardinal directions (N, S, E, W). It defines on which side the sun will rise.
- The third click sets the distance of the sun. Move the cursor up or down in one of the side views and click to place the sun, as shown in the figure below.
Animating the Daylight System
Once the Sun Positioner is created, you will need to animate it to create the shadow study at different times of the day. The following steps show you how to animate the Sun Positioner by keyframing it:
1. Start by setting the Frame Rate and Animation Time in the Time Configuration dialog box, as shown in the figure below. This sets the Time Slider.
2. Select the SunPositioner object that you created and verify that the Time Slider is located at a time of 0:0:0 (frame 0), as shown in the figure below. This will start a shadow study at frame 0.
3. In the Command Panel, select the Modify panel (
) to set the starting time and date of the animation. In the figure below, the time is set to 6h which represents 6:00 AM, and the date is set to the 21st of June, 2017.
4. In the Animation Controls, click Auto. While in Auto mode, drag the time slider to the end time of 0:30:0 which is the last time frame, as shown in the figure below.
5. At this last frame, change the sun’s position by changing the time to the time that you want the shadow study to end. For example, enter 19h which means 7:00 PM.
Saving the Animation
Render and save the animation to image files. The image files can be opened individually to study the shadows at a particular time of day or to create an animation where these still images are put together. Below are the steps to save the animation:
1. Open the Render Setup dialog box by clicking (
(Render Setup)) and set the Renderer and other settings such as Active Time Segment and Output Size as per your requirements. Some of the settings are shown in the figure below.
2. In the Render Output area of the Render Setup dialog box, click Files, as shown in the figure below.
3. Render the animation to still frames and enter a name. Select the type of file you want to save the rendered images as. For example, select JPEG File from the Save as type drop-down list, as shown in the figure below. Save the images, and in the JPEG Image Control, set the Quality. Then click OK.
4. Finally, click Render to begin animating the individual frames of the animation through the course of a day from the starting time (which was set to start at 6 AM) to the ending time of 7 PM.
5. In Windows Explorer, in the folder where you saved the files, note the rendered images at different frames. In the figures below, the images at different frames are shown. Note the shadows at different frames.
I hope that this blog gives you a basic understanding of how to create a daylight system and animate the Sun Positioner in the Autodesk 3ds Max software. I did not touch upon the other animation techniques in 3ds Max where you can animate the camera to create a turntable or a walkthrough animation. A detailed explanation along with some hands-on practices for creating other kinds of animations have been provided in our Autodesk 3ds Max 2024: Fundamentals learning guide.
About the Author
Follow on Linkedin More Content by Renu Muthoo
