Frustum Demo

This demo displays a frustum whose parameters can be adjusted with the gui controls:

• fov is the field of view that defines the angular extent of the scene that is visible to the camera
• aspectRatio controls the ratio of the field of view in the horizontal and vertical directions
• near and far define the range of distance from the camera over which the scene content is visible
  • red and green lines are drawn around the near and far planes, respectively
• eyeX, eyeY, and eyeZ specify the position of the camera (EYE location, shown by the MAGENTA ball)
• atX, atY, and atZ specify the AT point, where the camera is looking (shown by the CYAN ball)
• upX, upY, and upZ specify a vector that indicates the UP direction for the camera (shown in yellow)

In this demo, the code calculates the exact geometry, given the fov, aspectRatio, and other parameters.

Here is the function that sets up this camera: