pre-gif re-write

graphgif.scm

@@ -2,6 +2,8 @@
 
 (use-modules (cairo))
 
+(re-export (cairo-pattern-create-rgb . create-color))
+
 ;;;;;;;;;;;;;;;;;;;
 ;; Basic Drawing ;;
 ;;;;;;;;;;;;;;;;;;;
@@ -11,7 +13,6 @@
 
 (define-public black (cairo-pattern-create-rgb 0 0 0))
 (define-public white (cairo-pattern-create-rgb 1 1 1))
-(define-public red   (cairo-pattern-create-rgb 1 0 0))
 
 (define (edge-painter cr graph)
   (lambda (node)
@@ -33,7 +34,9 @@
   (lambda (node)
     (let ([x (caar node)]
 	  [y (cdar node)]
-	  [color (caddr node)])
+	  [color (if (null? (cddr node))
+		     white
+		     (caddr node))])
       (cairo-arc cr x y 4. 0. tau)
       (cairo-set-source cr color)
       (cairo-fill-preserve cr)