lRGBrange(3G)							 lRGBrange(3G)

NAME    [Toc]    [Back]

     lRGBrange - sets the range	of RGB colors used for depth-cueing

C SPECIFICATION    [Toc]    [Back]

     void lRGBrange(rmin, gmin,	bmin, rmax, gmax, bmax,	znear, zfar)
     short rmin, gmin, bmin, rmax, gmax, bmax;
     long znear, zfar;

PARAMETERS    [Toc]    [Back]

     rmin   expects the	minimum	value to be stored in the red bitplanes.

     gmin   expects the	minimum	value to be stored in the green	bitplanes.

     bmin   expects the	minimum	value to be stored in the blue bitplanes.

     rmax   expects the	maximum	value to be stored in the red bitplanes.

     gmax   expects the	maximum	value to be stored in the green	bitplanes.

     bmax   expects the	maximum	value to be stored in the blue bitplanes.

     znear  expects the	nearer screen z, to which the maximum colors are
	    mapped.

     zfar   expects the	farther	screen z, to which the minimum colors are
	    mapped.

DESCRIPTION    [Toc]    [Back]

     lRGBrange sets the	range of RGB colors used for depth-cueing in RGB mode.
     The screen	z range	[znear,	zfar] is mapped	linearly into the RGB color
     range [ (rmax,gmax,bmax), (rmin,gmin,bmin)	].  Screen z values nearer
     than znear	are mapped to (rmax,gmax,bmax);	screen z values	farther	than
     zfar are mapped to	(rmin,gmin,bmin).

     The valid range for znear and zfar	depends	on the state of	the
     GLC_ZRANGEMAP compatibility mode (see glcompat).  If it is	0, the valid
     range depends on the graphics hardware.  When multisample is enabled, and
     multisample buffers exist in the current framebuffer configuration	in the
     current drawmode, the minimum is the value	returned by
     getgconfig(GC_MS_ZMIN) and	the maximum is the value returned by
     getgconfig(GC_MS_ZMAX).  Otherwise, the minimum is	the value returned by
     getgconfig(GC_ZMIN) and the maximum is the	value returned by
     getgconfig(GC_ZMAX).  If the state	of the GLC_ZRANGEMAP compatibility
     mode is 1,	the minimum is 0x0 and the maximum is 0x7FFFFF.	 Znear and
     zfar should be chosen to be consistent with the near and far parameters
     passed to lsetdepth.  If near < far, then znear should be less than zfar.
     If	near > far, then znear should be greater than zfar.  In	either case,
     the range [near, far] should bound	the range [znear, zfar].







									Page 1






lRGBrange(3G)							 lRGBrange(3G)



SEE ALSO
     depthcue, getgdesc, glcompat, lsetdepth

NOTE    [Toc]    [Back]

     When using	this routine, you should always	explicitly set the
     GLC_ZRANGEMAP mode	of glcompat because its	default	is different on
     different models.


									PPPPaaaaggggeeee 2222