source files: [xc]thl.[ch]
(XG.3D-MAKE-IMAGE-GRL '(<fix> <fix>) [:JUST-LIKE <grl>] [:WANT :PIXEL-RED ] [:WANT :PIXEL-GREEN] [:WANT :PIXEL-BLUE ] [:WANT :PIXEL-ALPHA] )
This convenience function returns an instance of class-graphic-relation containing class-8-bit-float-array instances named :PIXEL-RED, :PIXEL-GREEN, and :PIXEL-BLUE. Currently, only two-dimensional image relations are supported.
If :JUST-LIKE is provided and is a graphic relation, the returned graphic relation will contain only a :PIXEL-RED array iff the :JUST-LIKE <grl> contains a :PIXEL-RED array, and similarly for :PIXEL-GREEN and :PIXEL-BLUE.
Otherwise, if :WANT is used to specify, the given :PIXEL-* arrays are installed.
Otherwise, all three :PIXEL-* arrays are installed.
Skandha4 often uses a grl with only a :PIXEL-GREEN array to represent gray-scale images, and image manipulation and display prims work correctly with these grls; the :JUST-LIKE parameter here provides a convenient way of creating a new grl of the same :PIXEL-* multiplicity as a given existing grl.