About Camera Objects

A camera object (or, more briefly, a camera ) is a type of QuickDraw 3D object that you use to define a point of view, a range of visible objects, and a method of projection for generating a two-dimensional image of those objects from a three-dimensional model. A camera is of type TQ3CameraObject , which is a type of shape object.

QuickDraw 3D defines three types of cameras:

• orthographic cameras
• view plane cameras
• aspect ratio cameras

These types of cameras differ in their methods of projection, as explained more fully later in this section. All three types of cameras share some basic properties, which are maintained in a camera data structure, defined by the TQ3CameraData data structure.

typedef struct TQ3CameraData {
    TQ3CameraPlacement                  placement;
    TQ3CameraRange                      range;
    TQ3CameraViewPort                   viewPort;
} TQ3CameraData;


These fields specify the location and orientation of the camera, the visible range of interest, and the camera's view port and projection method. The following sections explain these concepts in greater detail.

Camera Placements

Camera Ranges

View Planes and View Ports

Orthographic Cameras

View Plane Cameras

Aspect Ratio Cameras

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© 1997 Apple Computer, Inc.

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