179 |
} |
} |
180 |
|
|
181 |
/** |
/** |
182 |
|
* A BltBufferStrategy for canvases. |
183 |
|
*/ |
184 |
|
private class CanvasBltBufferStrategy extends BltBufferStrategy |
185 |
|
{ |
186 |
|
/** |
187 |
|
* Creates a block transfer strategy for this canvas. |
188 |
|
* |
189 |
|
* @param numBuffers the number of buffers in this strategy |
190 |
|
* @param accelerated true if the buffer should be accelerated, |
191 |
|
* false otherwise |
192 |
|
*/ |
193 |
|
CanvasBltBufferStrategy(int numBuffers, boolean accelerated) |
194 |
|
{ |
195 |
|
super(numBuffers, |
196 |
|
new BufferCapabilities(new ImageCapabilities(accelerated), |
197 |
|
new ImageCapabilities(accelerated), |
198 |
|
BufferCapabilities.FlipContents.COPIED)); |
199 |
|
} |
200 |
|
} |
201 |
|
|
202 |
|
/** |
203 |
|
* A FlipBufferStrategy for canvases. |
204 |
|
*/ |
205 |
|
private class CanvasFlipBufferStrategy extends FlipBufferStrategy |
206 |
|
{ |
207 |
|
/** |
208 |
|
* Creates a flip buffer strategy for this canvas. |
209 |
|
* |
210 |
|
* @param numBuffers the number of buffers in this strategy |
211 |
|
* |
212 |
|
* @throws AWTException if the requested number of buffers is not |
213 |
|
* supported |
214 |
|
*/ |
215 |
|
CanvasFlipBufferStrategy(int numBuffers) |
216 |
|
throws AWTException |
217 |
|
{ |
218 |
|
super(numBuffers, |
219 |
|
new BufferCapabilities(new ImageCapabilities(true), |
220 |
|
new ImageCapabilities(true), |
221 |
|
BufferCapabilities.FlipContents.COPIED)); |
222 |
|
} |
223 |
|
} |
224 |
|
|
225 |
|
/** |
226 |
|
* Creates a buffering strategy that manages how this canvas is |
227 |
|
* repainted. This method attempts to create the optimum strategy |
228 |
|
* based on the desired number of buffers. Hardware or software |
229 |
|
* acceleration may be used. |
230 |
|
* |
231 |
|
* createBufferStrategy attempts different levels of optimization, |
232 |
|
* but guarantees that some strategy with the requested number of |
233 |
|
* buffers will be created even if it is not optimal. First it |
234 |
|
* attempts to create a page flipping strategy, then an accelerated |
235 |
|
* blitting strategy, then an unaccelerated blitting strategy. |
236 |
|
* |
237 |
|
* Calling this method causes any existing buffer strategy to be |
238 |
|
* destroyed. |
239 |
|
* |
240 |
|
* @param numBuffers the number of buffers in this strategy |
241 |
|
* |
242 |
|
* @throws IllegalArgumentException if requested number of buffers |
243 |
|
* is less than one |
244 |
|
* @throws IllegalStateException if this canvas is not displayable |
245 |
|
* |
246 |
|
* @since 1.4 |
247 |
|
*/ |
248 |
|
public void createBufferStrategy(int numBuffers) |
249 |
|
{ |
250 |
|
if (numBuffers < 1) |
251 |
|
throw new IllegalArgumentException("Canvas.createBufferStrategy: number" |
252 |
|
+ " of buffers is less than one"); |
253 |
|
|
254 |
|
if (!isDisplayable()) |
255 |
|
throw new IllegalStateException("Canvas.createBufferStrategy: canvas is" |
256 |
|
+ " not displayable"); |
257 |
|
|
258 |
|
// try a flipping strategy |
259 |
|
try |
260 |
|
{ |
261 |
|
bufferStrategy = new CanvasFlipBufferStrategy(numBuffers); |
262 |
|
return; |
263 |
|
} |
264 |
|
catch (AWTException e) |
265 |
|
{ |
266 |
|
} |
267 |
|
|
268 |
|
// try an accelerated blitting strategy |
269 |
|
try |
270 |
|
{ |
271 |
|
bufferStrategy = new CanvasBltBufferStrategy(numBuffers, true); |
272 |
|
} |
273 |
|
catch (AWTException e) |
274 |
|
{ |
275 |
|
} |
276 |
|
|
277 |
|
// fall back to an unaccelerated blitting strategy |
278 |
|
try |
279 |
|
{ |
280 |
|
bufferStrategy = new CanvasBltBufferStrategy(numBuffers, false); |
281 |
|
} |
282 |
|
catch (AWTException e) |
283 |
|
{ |
284 |
|
} |
285 |
|
} |
286 |
|
|
287 |
|
/** |
288 |
|
* Creates a buffering strategy that manages how this canvas is |
289 |
|
* repainted. This method attempts to create a strategy based on |
290 |
|
* the specified capabilities and throws an exception if the |
291 |
|
* requested strategy is not supported. |
292 |
|
* |
293 |
|
* Calling this method causes any existing buffer strategy to be |
294 |
|
* destroyed. |
295 |
|
* |
296 |
|
* @param numBuffers the number of buffers in this strategy |
297 |
|
* @param caps the requested buffering capabilities |
298 |
|
* |
299 |
|
* @throws AWTException if the requested capabilities are not |
300 |
|
* supported |
301 |
|
* @throws IllegalArgumentException if requested number of buffers |
302 |
|
* is less than one or if caps is null |
303 |
|
* |
304 |
|
* @since 1.4 |
305 |
|
*/ |
306 |
|
public void createBufferStrategy(int numBuffers, |
307 |
|
BufferCapabilities caps) |
308 |
|
{ |
309 |
|
if (numBuffers < 1) |
310 |
|
throw new IllegalArgumentException("Canvas.createBufferStrategy: number" |
311 |
|
+ " of buffers is less than one"); |
312 |
|
|
313 |
|
if (caps == null) |
314 |
|
throw new IllegalArgumentException("Canvas.createBufferStrategy:" |
315 |
|
+ " capabilities object is null"); |
316 |
|
|
317 |
|
// a flipping strategy was requested |
318 |
|
if (caps.isPageFlipping()) |
319 |
|
{ |
320 |
|
try |
321 |
|
{ |
322 |
|
bufferStrategy = new CanvasFlipBufferStrategy(numBuffers); |
323 |
|
} |
324 |
|
catch (AWTException e) |
325 |
|
{ |
326 |
|
} |
327 |
|
} |
328 |
|
else |
329 |
|
bufferStrategy = new CanvasBltBufferStrategy(numBuffers, true); |
330 |
|
} |
331 |
|
|
332 |
|
/** |
333 |
* Returns the buffer strategy used by the canvas. |
* Returns the buffer strategy used by the canvas. |
334 |
* |
* |
335 |
* @return the buffer strategy. |
* @return the buffer strategy. |
362 |
/* Call the paint method */ |
/* Call the paint method */ |
363 |
paint(graphics); |
paint(graphics); |
364 |
} |
} |
|
|
|
365 |
} |
} |