Replaced the naive dynamic style system with the (dynamic) macro whic…

…h sets a special context

src/dali/backend.clj

@@ -37,7 +37,8 @@
   (render-path [this shape])
   (render-image [this shape])
 
-  (render-group [this shape]))
+  (render-group [this shape])
+  (text-bounds [this shape]))
 
 
 (defmacro delegate-op-to-backend [op & shape-types]

src/dali/backend/java_2d.clj

@@ -194,7 +194,7 @@
          size (.getSize *DEFAULT-FONT*)}}]
   (Font. family java.awt.Font/PLAIN size))
 
-(defn text-bounds
+(defn text-bounds-java-2d
   [backend {content :content {position :position} :geometry :as text}]
   (let [font (font->java-font (get-in text [:style :font]))
         rect (.getStringBounds
@@ -218,10 +218,12 @@
   (let [st (if (has-stroke? shape) (:stroke shape) DEFAULT-STROKE)]
     (isolate-style backend
      (set-stroke backend (eval-dynamic-style
+                          backend
                           shape
                           (get-in shape [:style :stroke])))
      (if (has-transform? shape)       
        (with-transform backend (eval-dynamic-style
+                                backend
                                 shape
                                 (:transform shape))
          (draw backend shape))
@@ -231,10 +233,12 @@
   (when (has-fill? shape)
     (isolate-style backend
       (set-fill backend (eval-dynamic-style
+                         backend
                          shape
                          (get-in shape [:style :fill])))
       (if (has-transform? shape)
         (with-transform backend (eval-dynamic-style
+                                 backend
                                  shape
                                  (:transform shape))          
           (fill backend shape))
@@ -323,7 +327,9 @@
               (assoc shape
                 :style (deep-merge (:style group)
                                    (:style shape)))] ;;shape takes precedence
-          (render this merged))))))
+          (render this merged)))))
+  (text-bounds [this shape]
+    (text-bounds-java-2d this shape)))
 
 (defn buffered-image-type [type]
   (if (keyword? type)

src/dali/core.clj

@@ -1,3 +1,4 @@
+
 (ns dali.core
   (:use [dali.math]
         [dali.utils]))
@@ -156,6 +157,13 @@
    {:type :group
     :content content}))
 
+(defmacro dynamic [& body]
+  {:type :dynamic-value
+   :code `'~body})
+
+(defn dynamic-value? [x]
+  (if (and (map? x)) (= :dynamic-value (:type x))))
+
 
 (defn rectangle->polygon
   [{{[px py] :position [w h] :dimensions} :geometry :as shape}]

src/dali/style.clj

@@ -135,9 +135,18 @@
      :stops stops
      :cycle-method cycle-method}))
 
-(defn eval-dynamic-style [shape style]
-  (postwalk (fn eval-dynamic-style-fn [x]
-              (if (function? x) (x shape) x)) style))
+(declare #^{:dynamic true} backend)
+(declare #^{:dynamic true} this)
+
+(defn eval-dynamic-style [the-backend shape style]
+  (binding [*ns* (the-ns 'dali.style)
+            backend the-backend
+            this shape]
+    (postwalk (fn eval-dynamic-style-fn [x]
+                (if (dynamic-value? x)
+                  (let [code (:code x)]                    
+                    (eval `(do ~@code)))
+                  x)) style)))
 
 ;;;;;; fills ;;;;;;
 

src/dali/test.clj

@@ -4,7 +4,7 @@
         [dali.math]
         [dali.backend]
         [dali.backend.java-2d])
-  (:require [clarity.dev :as dev])
+  (:require [dali.dev :as dev])
   (:import [java.awt.geom CubicCurve2D$Double Path2D$Double AffineTransform]))
 
 #_(dev/watch-image #(test-dali))
@@ -71,11 +71,11 @@
        (rectangle {:stroke {:width 8
                             :color (color 0 130 0)
                             :join :miter}
-                   :transform [:translate #(minus (center %))
+                   :transform [:translate (dynamic (minus (center this)))
                                :skew [0.2 0.2]
                                :scale 0.8
                                :rotate 30
-                               :translate center]}
+                               :translate (dynamic (center this))]}
                   [330 170] [100 70]))
 
       (draw (rotate-around (rectangle [160 100] [60 60])