B582-Spring 2000 - Programming Assignment #2

"Simple Modeler"

To create a simple 3D modeling application for the CAVE

Due: Thursday, Feb. 24 by 5:00pm (demo in lab or before)
Value: 100 points (20 pts for interface design, 80 for implementation)
Sample Executable: available here (right-click to save as, then use chmod 755 DemoPS2)
Additional code resources: TBA the week of 2/7.

Our goal is to implement a simple modeling package for the CAVE. Specific functions which should be incorporated in this modeler include:

the ability to select between different shapes (e.g. sphere, cube, cone, cylinder, octahedron, etc.)
the ability to select a diffuse color for the shape
the ability to determine the size, position, and orientation of the shape
the ability to select and modify the position and orientation of a shape
the ability to navigate through the environment

Begin by determining how you will map the above functions onto the standard interface provided by the CAVE. You may assume the use of the three wand buttons, the joystick, and the position and orientation of the wand (and, if desired, the head). Feel free to introduce distinct modes into the interface. Describe this mapping in a short text document; include brief explanations for why you chose the particular mapping for each function. (This portion is worth 20 points; creativity (without sacrificing functionality) will be rewarded.)
Run the sample executable and familiarize yourself with one possible implementation of the function set. My implementation works as follows:

To change the shape, hold down the left button and move the joystick up or down (y direction)
To change the color, hold down the left button and move the joystick left or right (x direction)
To change the position and orientation of the shape, simple move or rotate the wand.
To change the size of the shape, hold the middle button down; the shape will grow from its minimum size of 0.2 feet in each direction to a maximum size of 2.0 feet.
Releasing the middle button will place the object at the last position, orientation, and size
To reposition or reorient a placed shape, depress the right button while the wand is inside the bounding sphere of the object. While the right button is down, the selected shape should follow changes in the wand position and orientation.

Now code your version of the modeler as described in your design above. (This portion is worth 80 points.)

Delete a selected object
Provide for non-uniform scaling
Select a texture map for the object
Modify the shape and color of an object that has already been placed
Save a scene out in a simple file format; load a saved file via the command line
Anything else you can think of ?