generalize brush transformation to apply to a stipple

collects/racket/draw/private/brush.rkt

@@ -80,7 +80,7 @@
       (raise-type-error (init-name 'brush%)
                         "transformation-vector"
                         _transformation))
-    (when _gradient
+    (when (or _gradient _stipple)
       (set! transformation (transformation-vector->immutable
                             _transformation))))
 
@@ -114,9 +114,11 @@
   (define/public (get-transformation) transformation)
 
   (def/public (get-stipple) stipple)
-  (def/public (set-stipple [(make-or-false bitmap%) s]) 
+  (def/public (set-stipple [(make-or-false bitmap%) s] 
+                           [(make-or-false transformation-vector?) [t #f]])
     (check-immutable 'set-stipple)
-    (set! stipple s)))
+    (set! stipple s)
+    (set! transformation (and s t))))
 
 ;; ----------------------------------------
 

collects/racket/draw/private/dc.rkt

@@ -758,6 +758,16 @@
           (cairo_set_source cr p)
           (cairo_pattern_destroy p))))
 
+    (define/private (install-transformation transformation cr)
+      (when transformation
+        (cairo_identity_matrix cr)
+        (init-cr-matrix cr)
+        (cairo_translate cr scroll-dx scroll-dy)        
+        (cairo_transform cr (vector->matrix (vector-ref transformation 0)))
+        (cairo_translate cr (vector-ref transformation 1) (vector-ref transformation 2))
+        (cairo_scale cr (vector-ref transformation 3) (vector-ref transformation 4))
+        (cairo_rotate cr (- (vector-ref transformation 5)))))
+
     (define/private (make-gradient-pattern cr gradient transformation)
       (define p 
         (if (is-a? gradient linear-gradient%)
@@ -772,14 +782,7 @@
                  [b (norm (color-blue c))]
                  [a (color-alpha c)])
             (cairo_pattern_add_color_stop_rgba p offset r g b a)))
-      (when transformation
+      (install-transformation transformation cr)
-        (cairo_identity_matrix cr)
-        (init-cr-matrix cr)
-        (cairo_translate cr scroll-dx scroll-dy)        
-        (cairo_transform cr (vector->matrix (vector-ref transformation 0)))
-        (cairo_translate cr (vector-ref transformation 1) (vector-ref transformation 2))
-        (cairo_scale cr (vector-ref transformation 3) (vector-ref transformation 4))
-        (cairo_rotate cr (- (vector-ref transformation 5))))
       (cairo_set_source cr p)
       (when transformation
         (do-reset-matrix cr))
@@ -787,7 +790,7 @@
 
     ;; Stroke, fill, and flush the current path
     (define/private (draw cr brush? pen?)
-      (define (install-stipple st col mode get put)
+      (define (install-stipple st col mode transformation get put)
         (let ([s (cond
                   [(get) => (lambda (s) s)]
                   [(and (not (send st is-color?))
@@ -815,7 +818,10 @@
                               get-cairo-surface))])])
           (let* ([p (cairo_pattern_create_for_surface s)])
             (cairo_pattern_set_extend p CAIRO_EXTEND_REPEAT)
+            (install-transformation transformation cr)
             (cairo_set_source cr p)
+            (when transformation
+              (do-reset-matrix cr))
             (cairo_pattern_destroy p))))
       (cairo_set_antialias cr (case (dc-adjust-smoothing smoothing)
                                 [(unsmoothed) CAIRO_ANTIALIAS_NONE]
@@ -831,6 +837,7 @@
                   (make-gradient-pattern cr gradient (send brush get-transformation))
                   (if st
                       (install-stipple st col s 
+                                       (send brush get-transformation)
                                        (lambda () brush-stipple-s)
                                        (lambda (v) (set! brush-stipple-s v) v))
                       (let ([horiz (lambda (cr2)
@@ -896,6 +903,7 @@
                   [col (send pen get-color)])
               (if st
                   (install-stipple st col s
+                                   #f
                                    (lambda () pen-stipple-s)
                                    (lambda (v) (set! pen-stipple-s v) v))
                   (install-color cr 

collects/racket/draw/private/record-dc.rkt

@@ -54,12 +54,21 @@
     (if s
         (let ([b (make-object brush% 
                               (send b get-color)
-                              (send b get-style))])
+                              (send b get-style))]
-          (send b set-stipple (clone-bitmap s))
+              [t (send b get-transformation)])
+          (send b set-stipple (clone-bitmap s) t)
           b)
+        (let ([g (send b get-gradient)])
+          (if g
+              (make-object brush% 
+                           (send b get-color)
+                           (send b get-style)
+                           #f
+                           g
+                           (send b get-transformation))
               (send the-brush-list find-or-create-brush
                     (send b get-color)
-              (send b get-style)))))
+                    (send b get-style)))))))
 
 (define (region-maker r)
   (if (send r internal-get-dc)

collects/scribblings/draw/brush-class.scrbl

@@ -23,10 +23,11 @@ As an alternative to a color, style, and stipple, a brush can have a
  ending colors and starting and ending lines (for a linear gradient)
  or circles (for a radial gradient); a gradient-assigned color is
  applied for each point that is touched when drawing with the brush.
- By default, coordinates in the gradient are transformed by the
+
+By default, coordinates in a stipple or gradient are transformed by the
  drawing context's transformation when the brush is used, but a brush
- can have its own @deftech{gradient transformation} that is used, instead.
+ can have its own @deftech{brush transformation} that is used, instead.
- A gradient transformation has the same representation and meaning as for
+ A brush transformation has the same representation and meaning as for
  @xmethod[dc<%> get-transformation].
 
 A @deftech{brush style} is one of the following (but is ignored if the brush
@@ -102,10 +103,12 @@ To avoid creating multiple brushes with the same characteristics, use
                                                               real? real? real?)
                                                      real? real? real? real? real?))])]{
 
-Creates a brush with the given color, @tech{brush style}, @tech{brush stipple}, @tech{gradient}, and
+Creates a brush with the given color, @tech{brush style}, @tech{brush
- @tech{gradient transformation}. For the case that the color is specified
+ stipple}, @tech{gradient}, and @tech{brush transformation} (which is
- using a name, see @racket[color-database<%>] for information about
+ kept only if the gradient or stipple is non-@racket[#f]). For the
- color names; if the name is not known, the brush's color is black.}
+ case that the color is specified using a name, see
+ @racket[color-database<%>] for information about color names; if the
+ name is not known, the brush's color is black.}
 
 
 @defmethod[(get-color)
@@ -143,12 +146,12 @@ brush styles.}
 @defmethod[(get-transformation) (or/c #f (vector/c (vector/c real? real? real? real? real? real?)
                                                    real? real? real? real? real?))]{
 
-Returns the brush's @tech{gradient transformation}, if any.
+Returns the brush's @tech{brush transformation}, if any.
 
-If a brush with a gradient also has a transformation, then the
+If a brush with a stipple or gradient also has a transformation, then the
-transformation applies to the gradient's coordinates instead of the
+transformation applies to the stipple or gradient's coordinates instead of the
 target drawing context's transformation; otherwise, the target drawing
-context's transformation applies to gradient coordinates.}
+context's transformation applies to stipple and gradient coordinates.}
 
 
 @defmethod*[([(set-color [color (is-a?/c color%)])
@@ -169,12 +172,17 @@ For the case that the color is specified using a string, see
 
 }
 
-@defmethod[(set-stipple [bitmap (or/c (is-a?/c bitmap%) #f)])
+@defmethod[(set-stipple [bitmap (or/c (is-a?/c bitmap%) #f)]
+                 [transformation (or/c #f (vector/c (vector/c real? real? real? 
+                                                              real? real? real?)
+                                                     real? real? real? real? real?))
+                                 #f])
            void?]{
 
-Sets or removes the @tech{brush stipple} bitmap, where @racket[#f] removes the
+Sets or removes the @tech{brush stipple} bitmap, where @racket[#f]
- stipple. See @racket[brush%] for information about drawing with
+ removes the stipple. The @tech{brush transformation} is set at the
- stipples.
+ same time to @racket[transformation]. See @racket[brush%] for
+ information about drawing with stipples.
 
 If @racket[bitmap] is modified while is associated with a brush, the
  effect on the brush is unspecified. A brush cannot be modified if it