! Copyright (C) 2007, 2009 Slava Pestov.
! See http://factorcode.org/license.txt for BSD license.
USING: ui.backend ui.gadgets ui.gadgets.worlds ui.pens.solid opengl
opengl.gl kernel namespaces classes.tuple colors colors.constants
accessors ;
IN: ui.gadgets.canvas

TUPLE: canvas < gadget dlist ;

: new-canvas ( class -- canvas )
    new COLOR: black <solid> >>interior ; inline

: delete-canvas-dlist ( canvas -- )
    [ find-gl-context ]
    [ [ [ delete-dlist ] when* f ] change-dlist drop ] bi ;

: make-canvas-dlist ( canvas quot -- dlist )
    [ drop ] [ GL_COMPILE swap make-dlist ] 2bi
    [ >>dlist drop ] keep ; inline

: cache-canvas-dlist ( canvas quot -- dlist )
    over dlist>> dup
    [ 2nip ] [ drop make-canvas-dlist ] if ; inline

: draw-canvas ( canvas quot -- )
    cache-canvas-dlist glCallList ; inline

M: canvas ungraft* delete-canvas-dlist ;