AP Professional Graphics CD-ROM Library/AP Professional Graphics CD-ROM Library.iso/mac/Macintosh/Appendix/GemsIII/Source Code Gems III/luminaire/geometry_object.h

Text File | 1995-03-08 | 844 b | 29 lines | [TEXT/MSWD]

// ******************************************************************
//
// Physically Correct Direct Lighting For Distribution Ray Tracing
//             by Changyaw Wang
//
// geometry_object.h
//
// ******************************************************************

//  Abstract class geom_obj may be subclassed to a particular type of
//  object such as a sphere, or a triangle.

class point;

class geom_obj {
public:

    // Selects a point visible from x given (r1,r2).
    // Here, visible means not SELF-shadowed.

    virtual void select_visible_point(
             const point& x,   // viewpoint
             const double r1,  // random number
             const double r2,  // random number
             point& on_light,  // point corresponding to (r1,r2)
             double& prob);    // probability of selecting on_light
};