Lesson 14: Animation for Design

Lesson 13 showed you how to create a photorealistic image of a wire file model by rendering it. This lesson shows you how to animate a model. Alias includes two types of animation - turntable and autofly - that designers can use to quickly visualize and evaluate their models. Turntable and autofly are easy to set up and perform.

While turntable lets you pick objects and rotate them around an axis, autofly moves the camera around the objects. You set up an autofly by assigning curve paths for the eye point, viewpoint and upwards camera direction. The motion of the camera around these paths creates the animation. Once prepared, these animations can be shown on screen, or stored as SDL (Scene Description Language) files for rendering.

Initial Setup

You start this lesson by opening the fruit bowl.

Open a file

From the File menu, select Open. In the File lister, select L14_Fruit5 from the CourseWare project (or myfruitbowl5 from your own directory) and click on Open.

Setting the Turntable Options

In this section, you use turntable to rotate the scene.

Pick all objects in the scene

1. Select Pick Object Types All obj/lights to pick all the objects in the scene.

   Expand and adjust the Perspective window

2. From the Layouts window, select Perspective or click in the resize button on the top right of the window to get a full-screen perspective view.
3. Use the dolly tool to see more of the scene.

   Open the turntable option box

4. From the Preferences menu, make sure Long Menus is selected. To toggle on Long Menus, toggle off Short Menus. Long Menus makes more menu items available.
5. From the Animation menu, select Turntable-, to open the Turntable Options box:

   

   Set the axis and rotation parameters

6. Choose Z for the Axis option. This sets the axis around which the selected objects will rotate. (This assumes you are set up in a Z-up orientation.)
7. Click Positive for the turntable's direction. The Direction option determines if the objects rotate in a positive or negative direction around the chosen axis. For a Z-axis turntable in Z-up orientation, positive is counter-clockwise and negative is clockwise.
8. Click Origin for the Rotate About point. This option lets you choose between rotating about the world space origin (0,0,0) or the average of the objects' pivot point locations. Because the bowl was built at 0,0,0, you can leave the setting at Origin.

   Set the number of frames per revolution

   The Frames/Rev value determines the number of frames for each complete rotation. The higher the number, the slower the rotation.

9. Set the number of frames to 75.

   Turn off the Create SDL option

10. Make sure that the Create SDL File option is turned Off (unchecked).

    The Create SDL File option lets you write out an SDL file of the turntable animation that you can render later.

    Note: When rendering an existing SDL file, set the Geometry Source to SDL File, instead of Modeler, in the Miscellaneous section of Render Globals.... Later in this lesson, you'll use this method to render an autofly.

    Execute the turntable animation

11. Click Go. The entire scene rotates until you press the Esc key or click the mouse button anywhere on the screen.

Importing Curves for an Autofly

Now animate the camera instead of the objects. Autofly lets you move the camera around the scene by assigning parts of the camera to follow curves designated as motion paths. You can create walk-through or "fly-by" sequences of your design scene. Autofly uses NURBS curves to describe how camera parts move over time.

Open all four view windows

1. From the Layouts menu, select All windows All (Studio), to return to the four-window display.

   Import the wire file containing three curves

2. From the File menu, select Import File-. In the Import File options box, turn Keep Windows and Keep Camera to OFF. Click on Import File. In the File lister, click on the L14_fruit_cam icon. Click Retrieve.

   Adjust the Right window

   Three curves appear in the scene. These are standard NURBS curves, already created as camera guides.

3. Adjust the view in the Right window to see them clearly. Assigning the camera parts to these curves defines the animation camera paths.

   Note: The motion path curves are not visible when the animation is performed.

   The Perspective view now looks like this:

   

   Open the SBD window to see the camera

4. From the Windows menu, select SBD to open the SBD window. You can see the camera and its components in the SBD (Scene Block Diagram) window.

   .

   The camera group is located at the far right of the SBD. The SBD lists all elements of a scene, and shows the hierarchical structure of groupings. Some of the nodes (rectangles) represent the geometry information -others represent groupings and transformations. These are called DAG nodes.

5. Use the track icon (the one with intersecting double-arrows) to bring the camera into view.

   The three camera components are grouped under a root dag node. Below is a brief overview of each of the camera components:

   Eye - This is the node with the eye symbol. It represents the camera itself, or what you are looking through.

   View - This node has a target symbol, and represents where the camera is looking.

   Up Vector - This node has an up arrow and determines the camera angle.

   Close the SBD window

6. Having viewed the parts of the camera, close it by clicking on the close box in the top left corner of the window.

Setting the Autofly Options

Now you can set up and perform the autofly animation. First, you must set the size and the number of frames of your animation. Then, you save an SDL file with this animation to render later.

Check the render size

1. From the Render menu, select Globals.... Click on Image File Output to expand the menu. In the Predefined Resolutions section, select NTSC format.
2. Click on the close box to exit the Render Globals window.

   Set the start and end frames of the animation

3. From the Tool Palette, select Anim Autofly-. The middle set of parameters are Start Frame, End Frame and By Frames. Set the autofly to begin at frame 1 (Start Frame), end at frame 30 (End Frame), and go by 1 frame increments (By Frames).

   

   Tip: The animation has been set to 30 frames to reduce the rendering time. The frame size and the number of frames both affect how long it takes to render an animation. For test renderings, you should try to reduce both these parameters.

4. Set Maximum Bank to 0 degrees. The Auto Bank and Maximum Bank parameters determine whether the camera tilts into or away from the curve as it travels along the motion path, and the amount of the tilt. If Maximum Bank is 0, this function is disabled.

   Turn on the Create SDL option

5. Click in the box next to the Create SDL File to toggle on a check mark. The resulting SDL file can be rendered later.

   Close the option box

6. Click Go. The option box closes and you are prompted to: Select the motion path for the camera EYE to follow.

   Select the camera eye motion path

7. In the Perspective window, click on the middle level sloping curve, located between the other two curves. The camera eye will follow this curve through the scene.
8. The curve turns white momentarily to indicate it has been selected. You are prompted to: Select the motion path for the VIEW, or select the GO icon.

   

   Select the camera view motion path

9. Click on the bottom curve, which is the one closest to the fruit bowl and candle. The camera view will follow this curve throughout the animation.
10. When the Camera View path has been selected, you are prompted to: Select the motion path for the UP, or select the GO icon

    Select the Up motion path

11. Click on the top curve, and the message Computing autofly animation appears at the prompt line.
12. Next, the File lister appears so you can name the SDL file to be generated.

    Name the SDL file

13. Name the file Fruitfly01. Click Save SDL.

    A new camera is created for the rest of the animation and the perspective window shows the results. At the same time, the animation is saved as an SDL file. You can end the animation playback, at any time, by pressing the Esc key.

    Note: Unlike turntable, an autofly animation only appears in the Perspective view. This is because the Perspective window camera is the only object being animated.

Rendering the SDL File

When the autofly animation is performed with the Create SDL File option turned on, an SDL file is saved. Alias uses this SDL file to create the final rendered animation. SDL files are created for both single images and entire animation sequences.

Set the render globals

1. From the Render menu, select Globals.... Set Animation button to ON.
2. Click Miscellaneous to expand this section and set the Geometry Source to SDL File. This ensures that an SDL file (and not the modeler) is used as the source for rendering.
3. Close the Render Globals window.

   Render 30 frames using the Raycaster

4. From the Render menu, select Render -. Set the renderer type to Raycaster. Click Test Render. Change the test resolution to 0.5. Click Go.

   Note: A common technique is to perform a test render first so you can preview and test your animation. Once you are comfortable with it, you can render it at full size.

5. Select your animation SDL file (Fruitfly01) and click Render Sdl.

   Note: Once you start the renderer, it continues as an independent process. Even if you were to exit Alias and log out, the render continues until it is done.

6. From the Display menu, select Tgl render status to view the progress of your raycast.
7. From the Render menu, select Show render to watch the first frame as it is generated. To see any following frames, you need to reselect Show render.

Viewing the Rendered Animation

After all 30 frames have been rendered, you can use the Flipbook to view your animation.

Start Flipbook and Retrieve Animation

1. From the Animation menu, select Flipbook.The File lister is displayed. There are 30 pix files named FruitFly01.001 up to FruitFly01.030.

   Note: When Alias creates an animation, it generates one pix file for every frame of the animation.

2. Click on the pix file Fruitfly01.001. Click Show. This loads the animation files into the Flipbook.

   

   Preview the animation

3. Click the arrows to play back the animation. To learn more about Flipbook, see Animating in Alias.
4. You can enlarge the animation window by clicking on the square box at the right corner of the title bar.
5. Click the close button of the Flipbook window when you are finished.

Conclusion

You have now animated the fruit bowl using both turntable and autofly animations. These techniques allow designers to visualize, evaluate and explore their work in 3D. While turntable and autofly can give animators a feel for how their models look in motion, they should not be confused with Alias' true animation capabilities.