Areas and Plane Equations

A two-dimensional area is defined by the TQ3Area data type.

typedef struct TQ3Area {
    TQ3Point2D                          min;
    TQ3Point2D                          max;
} TQ3Area;


min

A two-dimensional point.

max

A two-dimensional point.

A plane equation is defined by the TQ3PlaneEquation data type.

typedef struct TQ3PlaneEquation {
    TQ3Vector3D                         normal;
    float                               constant;
} TQ3PlaneEquation;


normal

The vector that is normal (perpendicular) to the plane.

constant

The plane constant. A plane constant is the value d in the plane equation ax + by + cz + d = 0. The coefficients a , b , and c are the x , y , and z components of the normal vector.

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© 1997 Apple Computer, Inc.

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