1 /*
2 * Copyright (c) 2012, 2014, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation. Oracle designates this
8 * particular file as subject to the "Classpath" exception as provided
9 * by Oracle in the LICENSE file that accompanied this code.
10 *
11 * This code is distributed in the hope that it will be useful, but WITHOUT
12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14 * version 2 for more details (a copy is included in the LICENSE file that
15 * accompanied this code).
16 *
17 * You should have received a copy of the GNU General Public License version
18 * 2 along with this work; if not, write to the Free Software Foundation,
19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20 *
21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22 * or visit www.oracle.com if you need additional information or have any
23 * questions.
24 */
25
26 package javafx.scene.canvas;
27
28 import javafx.beans.property.DoubleProperty;
29 import javafx.beans.property.DoublePropertyBase;
30 import javafx.geometry.NodeOrientation;
31 import javafx.scene.Node;
32 import com.sun.javafx.geom.BaseBounds;
33 import com.sun.javafx.geom.RectBounds;
34 import com.sun.javafx.geom.transform.BaseTransform;
35 import com.sun.javafx.jmx.MXNodeAlgorithm;
36 import com.sun.javafx.jmx.MXNodeAlgorithmContext;
37 import com.sun.javafx.scene.DirtyBits;
38 import com.sun.javafx.scene.NodeHelper;
39 import com.sun.javafx.scene.canvas.CanvasHelper;
40 import com.sun.javafx.sg.prism.GrowableDataBuffer;
41 import com.sun.javafx.sg.prism.NGCanvas;
42 import com.sun.javafx.sg.prism.NGNode;
43
44 /**
45 * {@code Canvas} is an image that can be drawn on using a set of graphics
46 * commands provided by a {@code GraphicsContext}.
47 *
48 * <p>
49 * A {@code Canvas} node is constructed with a width and height that specifies the size
50 * of the image into which the canvas drawing commands are rendered. All drawing
51 * operations are clipped to the bounds of that image.
52 *
53 * <p>Example:</p>
54 *
55 * <p>
56 * <pre>
57 import javafx.scene.*;
58 import javafx.scene.paint.*;
59 import javafx.scene.canvas.*;
60
61 Group root = new Group();
62 Scene s = new Scene(root, 300, 300, Color.BLACK);
63
64 final Canvas canvas = new Canvas(250,250);
65 GraphicsContext gc = canvas.getGraphicsContext2D();
66
67 gc.setFill(Color.BLUE);
68 gc.fillRect(75,75,100,100);
69
70 root.getChildren().add(canvas);
71 * </pre>
72 * </p>
73 *
74 * @since JavaFX 2.2
75 */
76 public class Canvas extends Node {
77 static {
78 CanvasHelper.setCanvasAccessor(new CanvasHelper.CanvasAccessor() {
79 @Override
80 public NGNode doCreatePeer(Node node) {
81 return ((Canvas) node).doCreatePeer();
82 }
83
84 @Override
85 public void doUpdatePeer(Node node) {
86 ((Canvas) node).doUpdatePeer();
87 }
88 });
89 }
90 static final int DEFAULT_VAL_BUF_SIZE = 1024;
91 static final int DEFAULT_OBJ_BUF_SIZE = 32;
92 private static final int SIZE_HISTORY = 5;
93
94 private GrowableDataBuffer current;
95 private boolean rendererBehind;
96 private int recentvalsizes[];
97 private int recentobjsizes[];
98 private int lastsizeindex;
99
100 private GraphicsContext theContext;
101
102 {
103 // To initialize the class helper at the begining each constructor of this class
104 CanvasHelper.initHelper(this);
105 }
106
107 /**
108 * Creates an empty instance of Canvas.
109 */
110 public Canvas() {
111 this(0, 0);
112 }
113
114 /**
115 * Creates a new instance of Canvas with the given size.
116 *
117 * @param width width of the canvas
118 * @param height height of the canvas
119 */
120 public Canvas(double width, double height) {
121 this.recentvalsizes = new int[SIZE_HISTORY];
122 this.recentobjsizes = new int[SIZE_HISTORY];
123 setNodeOrientation(NodeOrientation.LEFT_TO_RIGHT);
124 setWidth(width);
125 setHeight(height);
126 }
127
128 private static int max(int sizes[], int defsize) {
129 for (int s : sizes) {
130 if (defsize < s) defsize = s;
131 }
132 return defsize;
133 }
134
135 GrowableDataBuffer getBuffer() {
136 NodeHelper.markDirty(this, DirtyBits.NODE_CONTENTS);
137 NodeHelper.markDirty(this, DirtyBits.NODE_FORCE_SYNC);
138 if (current == null) {
139 int vsize = max(recentvalsizes, DEFAULT_VAL_BUF_SIZE);
140 int osize = max(recentobjsizes, DEFAULT_OBJ_BUF_SIZE);
141 current = GrowableDataBuffer.getBuffer(vsize, osize);
142 theContext.updateDimensions();
143 }
144 return current;
145 }
146
147 boolean isRendererFallingBehind() {
148 return rendererBehind;
149 }
150
151 /**
152 * returns the {@code GraphicsContext} associated with this {@code Canvas}.
153 */
154 public GraphicsContext getGraphicsContext2D() {
155 if (theContext == null) {
156 theContext = new GraphicsContext(this);
157 }
158 return theContext;
159 }
160
161 /**
162 * Defines the width of the canvas.
163 *
164 * @profile common
165 * @defaultvalue 0.0
166 */
167 private DoubleProperty width;
168
169 public final void setWidth(double value) {
170 widthProperty().set(value);
171 }
172
173 public final double getWidth() {
174 return width == null ? 0.0 : width.get();
175 }
176
177 public final DoubleProperty widthProperty() {
178 if (width == null) {
179 width = new DoublePropertyBase() {
180
181 @Override
182 public void invalidated() {
183 NodeHelper.markDirty(Canvas.this, DirtyBits.NODE_GEOMETRY);
184 impl_geomChanged();
185 if (theContext != null) {
186 theContext.updateDimensions();
187 }
188 }
189
190 @Override
191 public Object getBean() {
192 return Canvas.this;
193 }
194
195 @Override
196 public String getName() {
197 return "width";
198 }
199 };
200 }
201 return width;
202 }
203
204 /**
205 * Defines the height of the canvas.
206 *
207 * @profile common
208 * @defaultvalue 0.0
209 */
210 private DoubleProperty height;
211
212 public final void setHeight(double value) {
213 heightProperty().set(value);
214 }
215
216 public final double getHeight() {
217 return height == null ? 0.0 : height.get();
218 }
219
220 public final DoubleProperty heightProperty() {
221 if (height == null) {
222 height = new DoublePropertyBase() {
223
224 @Override
225 public void invalidated() {
226 NodeHelper.markDirty(Canvas.this, DirtyBits.NODE_GEOMETRY);
227 impl_geomChanged();
228 if (theContext != null) {
229 theContext.updateDimensions();
230 }
231 }
232
233 @Override
234 public Object getBean() {
235 return Canvas.this;
236 }
237
238 @Override
239 public String getName() {
240 return "height";
241 }
242 };
243 }
244 return height;
245 }
246
247 private NGNode doCreatePeer() {
248 return new NGCanvas();
249 }
250
251 /*
252 * Note: This method MUST only be called via its accessor method.
253 */
254 private void doUpdatePeer() {
255 if (NodeHelper.isDirty(this, DirtyBits.NODE_GEOMETRY)) {
256 NGCanvas peer = NodeHelper.getPeer(this);
257 peer.updateBounds((float)getWidth(),
258 (float)getHeight());
259 }
260 if (NodeHelper.isDirty(this, DirtyBits.NODE_CONTENTS)) {
261 NGCanvas peer = NodeHelper.getPeer(this);
262 if (current != null && !current.isEmpty()) {
263 if (--lastsizeindex < 0) {
264 lastsizeindex = SIZE_HISTORY - 1;
265 }
266 recentvalsizes[lastsizeindex] = current.writeValuePosition();
267 recentobjsizes[lastsizeindex] = current.writeObjectPosition();
268 rendererBehind = peer.updateRendering(current);
269 current = null;
270 }
271 }
272 }
273
274 /**
275 * @treatAsPrivate implementation detail
276 * @deprecated This is an internal API that is not intended for use and will be removed in the next version
277 */
278 @Deprecated
279 @Override
280 protected boolean impl_computeContains(double localX, double localY) {
281 double w = getWidth();
282 double h = getHeight();
283 return (w > 0 && h > 0 &&
284 localX >= 0 && localY >= 0 &&
285 localX < w && localY < h);
286 }
287
288 /**
289 * @treatAsPrivate implementation detail
290 * @deprecated This is an internal API that is not intended for use and will be removed in the next version
291 */
292 @Deprecated
293 @Override
294 public BaseBounds impl_computeGeomBounds(BaseBounds bounds, BaseTransform tx) {
295 bounds = new RectBounds(0f, 0f, (float) getWidth(), (float) getHeight());
296 bounds = tx.transform(bounds, bounds);
297 return bounds;
298 }
299
300 /**
301 * @treatAsPrivate implementation detail
302 * @deprecated This is an internal API that is not intended for use and will be removed in the next version
303 */
304 @Deprecated
305 @Override
306 public Object impl_processMXNode(MXNodeAlgorithm alg,
307 MXNodeAlgorithmContext ctx) {
308 return alg.processLeafNode(this, ctx);
309 }
310 }