--- a/src/net/kryshen/indyvon/component.clj	Fri Aug 20 03:19:37 2010 +0400
+++ b/src/net/kryshen/indyvon/component.clj	Fri Aug 20 21:44:03 2010 +0400
@@ -23,6 +23,7 @@
         width (.width size)
         height (.height size)]
     (.clearRect graphics 0 0 width height)
+    ;; Setup the root layer context (move to core?).
     (binding [*graphics* graphics
               *font-context* (.getFontRenderContext graphics)
               *initial-transform* (.getTransform graphics)

--- a/src/net/kryshen/indyvon/core.clj	Fri Aug 20 03:19:37 2010 +0400
+++ b/src/net/kryshen/indyvon/core.clj	Fri Aug 20 21:44:03 2010 +0400
@@ -11,20 +11,39 @@
    (java.awt.event MouseListener MouseMotionListener)
    (java.awt.font FontRenderContext)))
 
+;;
+;; Layer context
+;;
+
 (def ^Graphics2D *graphics*)
+
 (def ^FontRenderContext *font-context*)
+
 (def ^Component *target*)
+
 (def *width*)
+
 (def *height*)
+
 (def ^Shape *clip*)
-(def *update*)
+
 (def *event-dispatcher*)
 
-(def ^AffineTransform *initial-transform*)
-(def ^AffineTransform *inverse-initial-transform*)
+(def ^{:doc "Fn to be called in a layer context to request redraw."}
+     *update*)
+
+(def ^{:tag AffineTransform
+       :doc "Initial transform associated with the graphics context"}
+     *initial-transform*)
+
+(def ^{:tag AffineTransform
+       :doc "Inversion of the initial transform associated with
+            the graphics context"}
+     *inverse-initial-transform*)
 
 (defrecord Theme [fore-color back-color alt-back-color border-color font])
 
+;; REMIND: use system colors, see java.awt.SystemColor.
 (defn default-theme []
   (Theme. Color/BLACK Color/LIGHT_GRAY Color/WHITE
           Color/BLUE (Font. "Sans" Font/PLAIN 12)))
@@ -35,6 +54,10 @@
 (defrecord Size [width height])
 (defrecord Bounds [x y width height])
 
+;;
+;; Core protocols and types
+;;
+
 (defprotocol Layer
   "Basic UI element."
   (render! [this])
@@ -77,46 +100,26 @@
             :center (/ (:height size) 2)
             :bottom (:height size)))))))
 
-(defn- ^Graphics2D make-graphics [^Graphics2D graphics x y w h]
-  (.create graphics x y w h))
-
-(defn- ^Graphics2D apply-theme [^Graphics2D graphics theme]
-  (doto graphics
-    (.setColor (:fore-color theme))
-    (.setFont (:font theme))))
-
-(defn intersect
-  "Compute intersection between a pair of rectangles (Bounds)."
-  ([b1 b2]
-     (let [x1 (:x b1)
-           y1 (:y b1)
-           x2 (:x b2)
-           y2 (:y b2)]
-       (intersect x1 y1 (+ x1 (:width b1)) (+ y1 (:height b1))
-                  x2 y2 (+ x2 (:width b2)) (+ y2 (:height b2)))))
-  ([x11 y11 x12 y12, x21 y21 x22 y22]
-     (let [x1 (max x11 x21)
-           y1 (max y11 y21)
-           x2 (min x12 x22)
-           y2 (min y12 y22)]
-       (Bounds. x1 y1 (- x2 x1) (- y2 y1)))))
+;;
+;; Rendering
+;;
 
 (defn- relative-transform
-  "AffineTransform: layer -> absolute -> component."
+  "AffineTransform: layer context -> awt component."
   []
   (let [tr (.getTransform *graphics*)]
     (.preConcatenate tr *inverse-initial-transform*)
     tr))
 
 (defn- inverse-relative-transform
-  "AffineTransform: component (event) -> absolute -> layer."
+  "AffineTransform: awt component -> layer context."
   []
   (let [tr (.getTransform *graphics*)]
     (.invert tr)                          ; absolute -> layer
     (.concatenate tr *initial-transform*) ; component -> absolute
     tr))
 
-(defn clip
+(defn- clip
   "Intersect clipping area with the specified shape or bounds.
    Returns new clip (Shape or nil if empty)."
   ([x y w h]
@@ -130,32 +133,43 @@
          nil
          a1))))
 
-(defn ^Graphics2D create-graphics
+(defn- ^Graphics2D apply-theme
+  "Set graphics' color and font to match theme.
+   Modifies and returns the first argument."
+  [^Graphics2D graphics theme]
+  (doto graphics
+    (.setColor (:fore-color theme))
+    (.setFont (:font theme))))
+
+(defn- ^Graphics2D create-graphics
   ([]
      (create-graphics 0 0 *width* *height*))
   ([x y w h]
      (apply-theme (.create *graphics* x y w h) *theme*)))
 
-(defmacro with-bounds [x y w h & body]
-  `(let [x# ~x, y# ~y
-         w# ~w, h# ~h
-         clip# (clip x# y# w# h#)]
-     (when clip#
-       (let [graphics# (create-graphics x# y# w# h#)]
-         (try
-           (binding [*width* w#
-                     *height* h#
-                     *clip* clip#
-                     *graphics* graphics#]
-             ~@body)
-           (finally
-            (.dispose graphics#)))))))
+(defn with-bounds*
+  [x y w h f & args]
+  (when-let [clip (clip x y w h)]
+    (let [graphics (create-graphics x y w h)]
+      (try
+        (binding [*width* w
+                  *height* h
+                  *clip* clip
+                  *graphics* graphics]
+          (apply f args))
+        (finally
+         (.dispose graphics))))))
 
-(defmacro with-handlers* [handle handlers & body]
-  `(binding
-       [*event-dispatcher*
-        (create-dispatcher *event-dispatcher* ~handle ~handlers)]
-     ~@body))
+(defmacro with-bounds
+  [x y w h & body]
+  `(with-bounds* ~x ~y ~w ~h (fn [] ~@body)))
+
+(defn with-handlers*
+  [handle handlers f & args]
+  (binding
+      [*event-dispatcher* (create-dispatcher
+                           *event-dispatcher* handle handlers)]
+    (apply f args)))
 
 (defmacro with-handlers
   "specs => (:event-id name & handler-body)*
@@ -168,17 +182,15 @@
                        `(fn [~(second spec)]
                           ~@(nnext spec)))) {}
                           specs)
-     ~form))
+     (fn [] ~form)))
 
-(defn with-theme* [theme f & args]
-  (apply with-bindings* {#'*theme* (merge *theme* theme)}
-         f args))
-
-(defmacro with-theme [theme & body]
+(defmacro with-theme
+  [theme & body]
   `(binding [*theme* (merge *theme* ~theme)]
      ~@body))
 
-(defmacro with-color [color & body]
+(defmacro with-color
+  [color & body]
   `(let [color# (.getColor *graphics*)]
      (try
        (.setColor *graphics* ~color)
@@ -212,6 +224,7 @@
     [(:x geometry) (:y geometry) (:width geometry) (:height geometry)]))
 
 (defn draw!
+  "Draws layer."
   ([layer]
      (let [graphics (create-graphics)]
        (try
@@ -223,11 +236,11 @@
      (let [size (layer-size layer)]
        (draw! layer x y (:width size) (:height size))))
   ([layer x y width height]
-     (with-bounds x y width height
-       (render! layer))))
+     (with-bounds* x y width height render! layer)))
 
 (defn draw-anchored!
-  "Draw with location relative to the anchor point."
+  "Draws layer. Location is relative to the layer's anchor point for
+   the specified alignment."
   ([layer h-align v-align x y]
      (let [anchor (anchor layer h-align v-align)]
        (draw! layer (- x (:x anchor)) (- y (:y anchor)))))