Mercurial > hg > indyvon
view src/net/kryshen/indyvon/async.clj @ 93:017f5f14b876
Async layer: use compatible BufferedImage.
| author | Mikhail Kryshen <mikhail@kryshen.net> |
|---|---|
| date | Thu, 23 Dec 2010 09:00:24 +0300 |
| parents | bf4a46f80851 |
| children | 649d12b6c9ec |
line source
1 ;;
2 ;; Copyright 2010 Mikhail Kryshen <mikhail@kryshen.net>
3 ;;
4 ;; This file is part of Indyvon.
5 ;;
6 ;; Indyvon is free software: you can redistribute it and/or modify it
7 ;; under the terms of the GNU Lesser General Public License version 3
8 ;; only, as published by the Free Software Foundation.
9 ;;
10 ;; Indyvon is distributed in the hope that it will be useful, but
11 ;; WITHOUT ANY WARRANTY; without even the implied warranty of
12 ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 ;; Lesser General Public License for more details.
14 ;;
15 ;; You should have received a copy of the GNU Lesser General Public
16 ;; License along with Indyvon. If not, see
17 ;; <http://www.gnu.org/licenses/>.
18 ;;
20 (ns net.kryshen.indyvon.async
21 "Asynchronous drawing."
22 (:use
23 net.kryshen.indyvon.core)
24 (:import
25 (net.kryshen.indyvon.core Size Location)
26 (java.awt Image AlphaComposite Transparency)
27 (java.awt.image BufferedImage)
28 (java.util.concurrent ThreadFactory ThreadPoolExecutor
29 ThreadPoolExecutor$DiscardOldestPolicy
30 ArrayBlockingQueue TimeUnit)))
32 (defrecord Buffer [id image readers state])
33 ;; Buffer states:
34 ;; :front, readers > 0
35 ;; being copied on screen
36 ;; :back
37 ;; being rendered to (offscreen)
38 ;; :fresh
39 ;; most recently updated
40 ;; :free
41 ;; not in use
43 (defn- create-image [async-layer]
44 ;; TODO: support different image types.
45 (.. *graphics* (getDeviceConfiguration)
46 (createCompatibleImage (:width async-layer) (:height async-layer)
47 Transparency/TRANSLUCENT)))
49 (defn- create-buffer [async-layer]
50 (Buffer. (Object.) (create-image async-layer) 0 :free))
52 (defn- find-buffer
53 "Find a buffer with the one of the specified states given
54 in the order of preference."
55 [buffers & states]
56 (some identity
57 (for [state states]
58 (some #(if (= (:state %) state) % nil) buffers))))
60 (defn- replace-buffer [buffers buffer]
61 (conj (remove #(= (:id %) (:id buffer)) buffers)
62 buffer))
64 (defn- take-buffer [al type]
65 (dosync
66 (let [buffers @(:buffers al)
67 b (case type
68 :front (find-buffer buffers :front :fresh :free)
69 :back (find-buffer buffers :free :fresh)
70 (throw (IllegalArgumentException.)))
71 readers (if (= type :front)
72 (inc (:readers b))
73 (:readers b))
74 b (assoc b
75 :state type
76 :readers readers)]
77 (alter (:buffers al) replace-buffer b)
78 b)))
80 (defn- release-buffer [al buffer]
81 (dosync
82 (let [state (:state buffer)
83 readers (if (= state :front)
84 (dec (:readers buffer))
85 (:readers buffer))
86 fresh (delay (find-buffer @(:buffers al) :fresh))
87 state (cond
88 (pos? readers) :front
89 (= :back state) :fresh
90 @fresh :free
91 :default :fresh)]
92 (if (and (= state :fresh) @fresh)
93 ;; Change state of the prefiously fresh buffer to :free.
94 (alter (:buffers al)
95 replace-buffer (assoc @fresh
96 :state :free)))
97 (alter (:buffers al)
98 replace-buffer (assoc buffer
99 :state state
100 :readers readers)))))
102 (defmacro with-buffer
103 {:private true}
104 [al type [name] & body]
105 `(let [al# ~al
106 ~name (take-buffer al# ~type)]
107 (try
108 ~@body
109 (finally
110 (release-buffer al# ~name)))))
112 (defn- draw-offscreen [async-layer]
113 ;;(Thread/sleep 1000)
114 (with-buffer async-layer :back [b]
115 (let [g (.createGraphics ^BufferedImage (:image b))]
116 ;; Clear the buffer.
117 (.setComposite g AlphaComposite/Clear)
118 (.fillRect g 0 0 (:width async-layer) (:height async-layer))
119 (.setComposite g AlphaComposite/Src)
120 (draw-root! (:content async-layer)
121 g
122 (:width async-layer)
123 (:height async-layer)
124 ;; TODO: use operational event dispatcher.
125 dummy-event-dispatcher))
126 (update async-layer)))
128 (defn- draw-offscreen-async [async-layer]
129 (.execute ^ThreadPoolExecutor (:executor async-layer)
130 #(draw-offscreen async-layer)))
132 (defrecord AsyncLayer [content width height executor buffers]
133 Layer
134 (render! [layer]
135 (repaint-on-update layer)
136 (add-context-observer content (fn [_ _] (draw-offscreen-async layer)))
137 (when-not @buffers
138 ;; TODO: dynamic size, recreate buffers when size increases.
139 (let [cb (bound-fn [] (create-buffer layer))
140 new-buffers (repeatedly 2 cb)]
141 (dosync
142 (ref-set buffers new-buffers)))
143 (draw-offscreen-async layer))
144 (with-buffer layer :front [b]
145 (.drawImage *graphics* ^Image (:image b) 0 0 nil)))
146 (layer-size [layer]
147 (Size. width height)))
149 (defn- create-thread-factory [priority]
150 (reify
151 ThreadFactory
152 (newThread [_ runnable]
153 (let [thread (Thread. runnable)]
154 (when priority
155 (.setPriority thread priority))
156 (.setDaemon thread true)
157 thread))))
159 (defn- create-executor [priority]
160 (doto (ThreadPoolExecutor.
161 (int 1) (int 1)
162 (long 0) TimeUnit/SECONDS
163 (ArrayBlockingQueue. 1)
164 (ThreadPoolExecutor$DiscardOldestPolicy.))
165 (.setThreadFactory (create-thread-factory priority))))
167 (defn async-layer
168 "Creates layer that draws the content asynchronously using
169 offscreen buffer."
170 ([content width height]
171 (async-layer content width height nil))
172 ([content width height priority]
173 (AsyncLayer. content width height
174 (create-executor priority)
175 (ref nil))))