topical media & game development

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bouncing balls


Study the examples below. However, first you may want to read the first chapters of the online tutorial. Also, you need to download the blaxxun VRML Contact3D plugin from

The examples contain variants of a bouncing ball, increasing in complexity and abstraction. Example 0 is based on the scripting example in lesson web3d/3. Example 2-5 elaborate on this example. The final example (5) gives a prototype (abstraction) with the acceleration as a parameter.



Modify example 4 including for example movement in the x or z direction, by extending the effect function, or by including damping.. Then transform this modification into a prototype as in example 5, providing an abstraction for color and speed.


Variants 6-9 contain combinations of bouncing ball entities, using the prototype abstraction facility. Have a look at these variants, but remind that, despite the visual effects, they primarily represent a software engineering effort.


Many of the attributes of this collection of examples, such as the roatation speed and colors, are implicit, that is built in in the code. You should strive to make such variables available for manipulation, by means of abstraction, using prototypes.


(C) Æliens 18/6/2009

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