gluProject与gluUnProject

gluProject

The gluProject function maps object coordinates to window coordinates.

int gluProject( GLdouble objx, GLdouble objy, GLdouble objz, const GLdouble modelMatrix[16], const GLdouble projMatrix[16], const GLint viewport[4], GLdouble *winx, GLdouble *winy, GLdouble *winz ); 

Parameters

objx, objy, objz

The object coordinates.

modelMatrix

The current modelview matrix (as from a glGetDoublev call).

projMatrix

The current projection matrix (as from a glGetDoublev call).

viewport

The current viewport (as from a glGetIntegerv call).

winx, winy, winz

The computed window coordinates.

Remarks

The gluProject function transforms the specified object coordinates into window coordinates usingmodelMatrix, projMatrix, and viewport. The result is stored inwinx, winy, and winz. A return value of GL_TRUE indicates success, and GL_FALSE indicates failure.

 

gluUnProject

The gluUnProject function maps window coordinates to object coordinates.

int gluUnProject( GLdouble winx, GLdouble winy, GLdouble winz, const GLdouble modelMatrix[16], const GLdouble projMatrix[16], const GLint viewport[4], GLdouble *objx, GLdouble *objy, GLdouble *objz ); 

Parameters

winx, winy, winz

The window coordinates to be mapped.

modelMatrix

The modelview matrix (as from a glGetDoublev call).

projMatrix

The projection matrix (as from a glGetDoublev call).

viewport

The viewport (as from a glGetIntegerv call).

objx, objy, objz

The computed object coordinates.

Return Values

If the function succeeds, the return value is GL_TRUE.

If the function fails, the return value is GL_FALSE.

Remarks

The gluUnProject function maps the specified window coordinates into object coordinates usingmodelMatrix, projMatrix, and viewport. The result is stored inobjx, objy, and objz.

Requirements

  Windows NT/2000: Requires Windows NT 3.5 or later.
  Windows 95/98: Requires Windows 95 or later. Available as a redistributable for Windows 95.
  Header: Declared in Glu.h.
  Library: Use Glu32.lib.

源自：http://blog.sina.com.cn/s/blog_4bb59dc401016gwr.html