RIDE #1 : This animated model was created as follows:

1. The model was created using an excellent (and FREE) interactive modeler called AC3D. Each of the four basic parts (car, fourarms, bigarm, base) were stored in a separate model files within their own local coordinate systems that were convenient for animation.
2. Each model was exported to a raw triangle format ("triangles") and read into my OpenGL viewer.
3. A hierarchical system of transformations was created by associating a "child-to-parent" instancing and animation matrix with each model occurrence. Each unique part of the model is stored only once. So, to display each frame, each model part is transformed for its current animation step with respect to its local coordinate system and then instanced multiple times (if necessary). The transformations are accumulated from the "base" to the "chair".

AC3D model files: base.ac, bigarm.ac, fourarms.ac, chair.ac.

RIDE #2 - COASTER :

• Basically, several types of track sections were created and stored. The coaster was then built by connecting these basic pieces into various looping configurations. Only ONE symmetric "flip" was required.
• I wanted to animate this coaster, but there wasn't enough time to write a "track-finding" routine. I have no path information for the car to travel on so I'll have to automatically detect the next animation step. I am currently thinking of ways of doing this.

COASTER CAR:

• This is a screen capture taken from my OpenGL viewer. The model was read in as "triangle soup", but was then converted to a shared-vertex format w/ vertex normals. This causes corners to appear rounded and also introduced shading artifacts as a result of Gouraud interpolation.
  

Sarah's BEAR :

• After receiving so many compliments while animating this model in the OpenGL viewer, I just had to put the bear that Sarah (my wife) made on this page too. This is the first time she has ever used any kind of 3D modeler, and this was her first model!! And to think, I will be doing 3D graphics as a profession.

AC3D model file: bear.ac