How to Make Computer Animationby Jackson Lewis
Creating computer animation is the first step of advanced graphics programming. Computer animation refers to the ability to change a component or aspect of an object (position, size, angle, color) over a defined time frame. In the past, it took complex computer programming to make basic computer-animated scenes. With the adoption of the 3-D graphics standard for the Internet, X3D, the ability to create computer animation for a graphics scene has been decoupled from the advanced programming skills previously required to do so. Content creators can focus on creating advanced animations without having to worry as much about the technical workings that occur behind the animation.
Download and install the latest version of the X3D-Edit 3D authoring tool and an X3D browser plug-in for scene viewing from the Web3D consortium (see Resources below).
Open X3D-Edit and load a sample animation scene from the X3D-examples library. Use the PositionInterporolator Scene Graph node in the moving box X3D scene to change the position value of the box shape in the example scene.
Initiate an X3D scene animation with a trigger. Load the X3D scene in the Web browser to trigger the animated box scene. Using a touchSensor is another common technique.
Seed the time for the animation using a TimeSensor node. The cycleInterval of the TimeSensor node determines the total length of the animated scene. To repeat the animation for the duration of the viewing of the X3D scene, the loop variable of the TimeSensor is set to "True." The default value for the loop variable is to run the animated scene exactly one time. The TimeSensor in the animated box scene is set to repeat the animation an infinite number of times.
Connect node output values in the animation using routes. For the moving box scene, send the fraction_changed field value from the TimeSensor to the position interpolator's set_fraction field to provide the interpolator time values to change the position of the box.
Route the position interpolator's value_changed field to the Transform node of the red box in the scene. This route changes the position of the box based on the output values of the interpolator.
View the example MovingBox X3D scene in an X3D browser by selecting the "View Scene" menu option.
Reopen the example file in X3D-Edit and change the values in the Position Interpolator node by 0.5 to 1, save the file and view the scene again in the X3D browser to observe the change in position of the box animation.
- check Always include a TimeSensor to provide the time input into the Interpolator node you are using in the X3D scene.
- photo_camera Screen shot taken by the author