Megatest

(use canvas-draw iup)
(import canvas-draw-iup)

(load "vg.scm")

(define d1 (vg:drawing-new))
(define l1 (vg:lib-new))
(define c1 (vg:comp-new))
(let ((r1 (vg:make-rect 20 20 40 40))
      (r2 (vg:make-rect 40 40 80 80)))
  (vg:add-objs-to-comp c1 r1 r2))

;; add the c1 component to lib l1 with name firstcomp
(vg:add-comp-to-lib l1 "firstcomp" c1)

;; add the l1 lib to drawing with name firstlib
(vg:add-lib d1 "firstlib" l1)

;; instantiate firstlib/firstcomp as inst1 in drawing d1 at 0,0
(vg:instantiate d1 "firstlib" "firstcomp" "inst1" 0 0)
(vg:instantiate d1 "firstlib" "firstcomp" "inst2" 200 200)
;; (vg:drawing-scalex-set! d1 2)

(define cnv #f)
(define the-cnv (canvas 
		 #:size "500x400"
		 #:expand "YES"
		 #:scrollbar "YES"
		 #:posx "0.5"

(use canvas-draw iup)
(import canvas-draw-iup)
;; structs
;;
(defstruct vg:lib     comps)
(defstruct vg:comp    objs name file)
(defstruct vg:obj     type pts fill-color text line-color call-back font)
(defstruct vg:inst    libname compname theta xoff yoff scalex scaley mirrx mirry call-back cache)
(defstruct vg:drawing libs insts scalex scaley xoff yoff cnv cache) ;; libs: hash of name->lib, insts: hash of instname->inst

;; inits
;;
(define (vg:comp-new)
  (make-vg:comp objs: '() name: #f file: #f))

(define (vg:lib-new)
  (make-vg:lib comps: (make-hash-table)))

(define (vg:drawing-new)
  (make-vg:drawing scalex: 1 
		   scaley: 1 
		   xoff: 0 
		   yoff: 0 
		   libs: (make-hash-table) 
		   insts: (make-hash-table)
		   cache: '()))

;;======================================================================
;; scaling and offsets
;;======================================================================

(define-inline (vg:scale-offset val s o)
  (+ o (* val s)))
  ;; (* (+ o val) s))

;; apply scale and offset to a list of x y values
;;
(define (vg:scale-offset-xy lstxy sx sy ox oy)
  (if (> (length lstxy) 1) ;; have at least one xy pair
      (let loop ((x   (car lstxy))
		 (y   (cadr lstxy))

   (vg:inst-scaley inst)
   (vg:inst-xoff   inst)
   (vg:inst-yoff   inst)))

;; apply both drawing and instance scaling to a list of xy points
;; 
(define (vg:drawing-inst-apply-scale-offset drawing inst lstxy)
  (vg:drawing-apply-scale 
   drawing
   (vg:inst-apply-scale inst lstxy)))

;;   (vg:inst-apply-scale 
;;    inst
;;    (vg:drawing-apply-scale drawing lstxy)))

;; make a rectangle obj
;;
(define (vg:make-rect x1 y1 x2 y2 #!key (line-color #f)(fill-color #f))
  (make-vg:obj type: 'r pts: (list x1 y1 x2 y2) text: #f line-color: line-color fill-color: fill-color))

;; get extents, use knowledge of type ...

;; add comp to lib
;;
(define (vg:add-comp-to-lib lib compname comp)
  (hash-table-set! (vg:lib-comps lib) compname comp))

;; instanciate component in drawing
;;
(define (vg:instantiate drawing libname compname instname xoff yoff #!key (theta 0)(scalex 1)(scaley 1)(mirrx #f)(mirry #f))
  (let ((inst (make-vg:inst libname: libname compname: compname xoff: xoff yoff: yoff theta: theta scalex: scalex scaley: scaley mirrx: mirrx mirry: mirry)) )
    (hash-table-set! (vg:drawing-insts drawing) instname inst)))

;; get component from drawing (look in apropriate lib) given libname and compname
(define (vg:get-component drawing libname compname)
  (let* ((lib  (hash-table-ref (vg:drawing-libs drawing) libname))
	 (inst (hash-table-ref (vg:lib-comps lib) compname)))
    inst))

  (let ((res (make-vg:obj type:       'r
			  fill-color: (vg:obj-fill-color obj)
			  text:       (vg:obj-text       obj)
			  line-color: (vg:obj-line-color obj)
			  font:       (vg:obj-font       obj)))
	(pts (vg:obj-pts obj)))
    (vg:obj-pts-set! res (vg:drawing-inst-apply-scale-offset drawing inst pts))
    (vg:drawing-cache-set! drawing (cons res (vg:drawing-cache drawing) ))
    res))

;;======================================================================
;; Unravel and draw the objects
;;======================================================================

(define (vg:draw-obj drawing obj)
  (print "obj type: " (vg:obj-type obj))
  (case (vg:obj-type obj)
    ((r)(vg:draw-rect drawing obj))))

;; given a rect obj draw it on the canvas applying first the drawing
;; scale and offset
;;
(define (vg:draw-rect drawing obj)
  (let* ((cnv (vg:drawing-cnv drawing))
	 (pts (vg:drawing-apply-scale drawing (vg:obj-pts obj)))
	 (llx (car pts))
	 (lly (cadr pts))
	 (ulx (caddr pts))
	 (uly (cadddr pts)))
    (print "pts: " pts)
    (canvas-rectangle! cnv llx ulx lly uly)))

(define (vg:draw drawing)
  (let ((insts (vg:drawing-insts drawing)))
    (for-each 
     (lambda (inst)
       (let* ((libname  (vg:inst-libname inst))
	      (compname (vg:inst-compname inst))
	      (comp     (vg:get-component drawing libname compname)))
	 (print "comp: " comp)
	 (for-each
	  (lambda (obj)
	    (print "obj: " (vg:obj-pts obj))
	    (let ((obj-xfrmd (vg:map-obj drawing inst obj)))
	      (print "obj-xfrmd: " (vg:obj-pts obj-xfrmd))
	      (vg:draw-obj drawing obj-xfrmd))) ;;
	  (vg:comp-objs comp))))
    (hash-table-values insts))))