summaryrefslogtreecommitdiffstats
path: root/src/net/java/games/jogl/impl/GLContext.java
blob: e0def092a4645cf614bfbb6afd29e0e037942fe0 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
/*
 * Copyright (c) 2003 Sun Microsystems, Inc. All Rights Reserved.
 * 
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are
 * met:
 * 
 * - Redistribution of source code must retain the above copyright
 *   notice, this list of conditions and the following disclaimer.
 * 
 * - Redistribution in binary form must reproduce the above copyright
 *   notice, this list of conditions and the following disclaimer in the
 *   documentation and/or other materials provided with the distribution.
 * 
 * Neither the name of Sun Microsystems, Inc. or the names of
 * contributors may be used to endorse or promote products derived from
 * this software without specific prior written permission.
 * 
 * This software is provided "AS IS," without a warranty of any kind. ALL
 * EXPRESS OR IMPLIED CONDITIONS, REPRESENTATIONS AND WARRANTIES,
 * INCLUDING ANY IMPLIED WARRANTY OF MERCHANTABILITY, FITNESS FOR A
 * PARTICULAR PURPOSE OR NON-INFRINGEMENT, ARE HEREBY EXCLUDED. SUN
 * MIDROSYSTEMS, INC. ("SUN") AND ITS LICENSORS SHALL NOT BE LIABLE FOR
 * ANY DAMAGES SUFFERED BY LICENSEE AS A RESULT OF USING, MODIFYING OR
 * DISTRIBUTING THIS SOFTWARE OR ITS DERIVATIVES. IN NO EVENT WILL SUN OR
 * ITS LICENSORS BE LIABLE FOR ANY LOST REVENUE, PROFIT OR DATA, OR FOR
 * DIRECT, INDIRECT, SPECIAL, CONSEQUENTIAL, INCIDENTAL OR PUNITIVE
 * DAMAGES, HOWEVER CAUSED AND REGARDLESS OF THE THEORY OF LIABILITY,
 * ARISING OUT OF THE USE OF OR INABILITY TO USE THIS SOFTWARE, EVEN IF
 * SUN HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES.
 * 
 * You acknowledge that this software is not designed or intended for use
 * in the design, construction, operation or maintenance of any nuclear
 * facility.
 * 
 * Sun gratefully acknowledges that this software was originally authored
 * and developed by Kenneth Bradley Russell and Christopher John Kline.
 */

package net.java.games.jogl.impl;

import java.awt.Component;
import java.awt.EventQueue;
import net.java.games.jogl.*;
import net.java.games.gluegen.runtime.*;

public abstract class GLContext {
  protected static final boolean DEBUG = false;

  static {
    NativeLibLoader.load();
  }

  protected Component component;

  // Indicates whether the component (if an onscreen context) has been
  // realized. Plausibly, before the component is realized the JAWT
  // should return an error or NULL object from some of its
  // operations; this appears to be the case on Win32 but is not true
  // at least with Sun's current X11 implementation (1.4.x), which
  // crashes with no other error reported if the DrawingSurfaceInfo is
  // fetched from a locked DrawingSurface during the validation as a
  // result of calling show() on the main thread. To work around this
  // we prevent any JAWT or OpenGL operations from being done until
  // the first event is received from the AWT event dispatch thread.
  private boolean realized;

  protected GLCapabilities capabilities;
  protected GLCapabilitiesChooser chooser;
  protected GL gl;
  // All GLU interfaces eventually route calls down to gluRoot. It can be
  // static because GLU it doesn't actually need to own context, it just makes
  // GL calls and assumes some context is active.
  protected static final GLUProcAddressTable gluProcAddressTable = new GLUProcAddressTable();
  protected static final GLU gluRoot = new GLUImpl(gluProcAddressTable);
  protected static boolean haveResetGLUProcAddressTable;
  protected GLU glu = gluRoot; // this is the context's GLU interface
  protected Thread renderingThread;
  protected Runnable deferredReshapeAction;

  // Error checking for setRenderingThread to ensure that one thread
  // doesn't attempt to call setRenderingThread on more than one
  // drawable
  protected static final ThreadLocal perThreadRenderingContext = new ThreadLocal();

  // This is a workaround for a bug in NVidia's drivers where
  // vertex_array_range is only safe for single-threaded use; a bug
  // has been filed, ID 80174. When an Animator is created for a
  // GLDrawable, the expectation is that the Animator will be started
  // shortly and that the user doesn't want rendering to occur from
  // the AWT thread. However, there is a small window between when the
  // Animator is created and attached to the GLDrawable and when it's
  // started (and sets the rendering thread) when repaint events can
  // be issued by the AWT thread if the component is realized. To work
  // around this problem, we currently specify in the Animator's API
  // that between the time it's created and started no redraws will
  // occur.
  protected volatile boolean willSetRenderingThread;

  // Flag for disabling all repaint and resize processing on the AWT
  // thread to avoid application-level deadlocks; only really used for
  // GLCanvas
  protected boolean noAutoRedraw;

  // Offscreen context handling. Offscreen contexts should handle
  // these resize requests in makeCurrent and clear the
  // pendingOffscreenResize flag.
  protected boolean pendingOffscreenResize;
  protected int     pendingOffscreenWidth;
  protected int     pendingOffscreenHeight;

  // Cache of the functions that are available to be called at the current
  // moment in time
  protected FunctionAvailabilityCache functionAvailability;

  // Support for recursive makeCurrent() calls as well as calling
  // other drawables' display() methods from within another one's
  protected static final ThreadLocal perThreadContextStack = new ThreadLocal() {
      protected synchronized Object initialValue() {
        return new GLContextStack();
      }
    };
      
  public GLContext(Component component,
                   GLCapabilities capabilities,
                   GLCapabilitiesChooser chooser,
                   GLContext shareWith) {
    this.component = component;
    try {
      this.capabilities = (GLCapabilities) capabilities.clone();
    } catch (CloneNotSupportedException e) {
      throw new GLException(e);
    }
    this.chooser = chooser;
    gl = createGL();
    functionAvailability = new FunctionAvailabilityCache(this);
    if (shareWith != null) {
      GLContextShareSet.registerSharing(this, shareWith);
    }
  }

  /** Runs the given runnable with this OpenGL context valid. */
  public synchronized void invokeGL(Runnable runnable, boolean isReshape, Runnable initAction) throws GLException {
    // Could be more clever about not calling this every time, but
    // Thread.currentThread() is very fast and this makes the logic simpler
    Thread currentThread = Thread.currentThread();
    
    // Defer JAWT and OpenGL operations until onscreen components are
    // realized
    if (!realized()) {
      realized = EventQueue.isDispatchThread();
    }

    if (!realized() ||
	willSetRenderingThread ||
        (renderingThread != null &&
         renderingThread != currentThread)) {
      if (isReshape) {
        deferredReshapeAction = runnable;
      }
      return;
    }

    if (isReshape && noAutoRedraw) {
      // Don't process reshape requests on the AWT thread
      deferredReshapeAction = runnable;
      return;
    }

    GLContextStack ctxStack = getPerThreadContextStack();
    GLContext curContext = ctxStack.peekContext();
    Runnable  curInitAction = ctxStack.peekInitAction();
    boolean mustDoMakeCurrent = true;
    boolean mustSkipFreeForRenderingThread = false;
    boolean mustFreeBecauseOfNoRenderingThread = false;

    if (curContext == this) {
      mustDoMakeCurrent = false;
    }

    if (currentThread == renderingThread && curContext == null) {
      mustSkipFreeForRenderingThread = true;
    }
    
    if (!mustDoMakeCurrent &&
        renderingThread == null &&
        ctxStack.size() == 1) {
      mustFreeBecauseOfNoRenderingThread = true;
    }
    
    if (mustDoMakeCurrent) {
      if (curContext != null) {
        if (DEBUG) {
          System.err.println("Freeing context " + curContext + " due to recursive makeCurrent");
        }
        curContext.free();
      }

      if (!makeCurrent(initAction)) {
        // Couldn't make the thread current because the component has not yet
        // been visualized, and therefore the context cannot be created.
        // We'll defer any actions until invokeGL() is called again at a time
        // when the component has been visualized.
        if (isReshape) {
          deferredReshapeAction = runnable;
        }
        return;
      }
      if (DEBUG) {
        System.err.println("Making context " + this + " current");
      }
    }
    ctxStack.push(this, initAction);

    // At this point the OpenGL context is current. Offscreen contexts
    // handle resizing the backing bitmap in makeCurrent. Therefore we
    // may need to free and make the context current again if we
    // didn't actually make it current above.
    if (pendingOffscreenResize && renderingThread != null) {
      ctxStack.pop();
      free();
      if (!makeCurrent(initAction)) {
        throw new GLException("Error while resizing offscreen context");
      }
      ctxStack.push(this, initAction);
    }

    boolean caughtException = false;

    try {
      if (deferredReshapeAction != null) {
        deferredReshapeAction.run();
        deferredReshapeAction = null;
      }
      runnable.run();
      swapBuffers();
    } catch (RuntimeException e) {
      caughtException = true;
      throw(e);
    } finally {
      if (caughtException) {
        // Disallow setRenderingThread if display action is throwing exceptions
        renderingThread = null;
      }

      if (!mustFreeBecauseOfNoRenderingThread && !mustSkipFreeForRenderingThread) {
        ctxStack.pop();
      }

      // Free the context if another one was current, but not if the
      // setRenderingThread optimization kicks in. However, if the
      // setRenderingThread optimization has recently been disabled,
      // must force a free.
      if ((mustDoMakeCurrent && !mustSkipFreeForRenderingThread) ||
          mustFreeBecauseOfNoRenderingThread) {
        if (mustFreeBecauseOfNoRenderingThread) {
          // Must match previous push()
          ctxStack.pop();
        }

        if (DEBUG) {
          System.err.println("Freeing context " + this);
        }

        free();

        if (curContext != null && !mustFreeBecauseOfNoRenderingThread) {
          if (DEBUG) {
            System.err.println("Making context " + curContext + " current again");
          }
          curContext.makeCurrent(curInitAction);
        }
      }
    }
  }

  public GL getGL() {
    return gl;
  }

  public void setGL(GL gl) {
    this.gl = gl;
  }

  public GLU getGLU() {    
    return glu;
  }
  
  public void setGLU(GLU glu) {
    this.glu = glu;
  }
  
  /** Gives a hint to the context that setRenderingThread will be
      called in the near future; causes redraws to be halted. This is
      a workaround for bugs in NVidia's drivers and is used only by
      the Animator class. */
  public synchronized void willSetRenderingThread() {
    this.willSetRenderingThread = true;
  }

  public synchronized void setRenderingThread(Thread currentThreadOrNull, Runnable initAction) {
    Thread currentThread = Thread.currentThread();
    if (currentThreadOrNull != null && currentThreadOrNull != currentThread) {
      throw new GLException("Argument must be either the current thread or null");
    }
    if (renderingThread != null && currentThreadOrNull != null) {
      throw new GLException("Attempt to re-set or change rendering thread");
    }
    if (renderingThread == null && currentThreadOrNull == null) {
      throw new GLException("Attempt to clear rendering thread when already cleared");
    }

    Object currentThreadRenderingContext = perThreadRenderingContext.get();
    if (currentThreadOrNull != null &&
        currentThreadRenderingContext != null &&
        currentThreadRenderingContext != this) {
      throw new GLException("Attempt to call setRenderingThread on more than one drawable in this thread");
    }

    this.willSetRenderingThread = false;
    if (currentThreadOrNull == null) {
      renderingThread = null;
      perThreadRenderingContext.set(null);
      // Just in case the end user wasn't planning on drawing the
      // drawable even once more (which would give us a chance to free
      // the context), try to free the context now by performing an
      // invokeGL with a do-nothing action
      invokeGL(new Runnable() {
          public void run() {
          }
        }, false, initAction);
    } else {
      renderingThread = currentThreadOrNull;
      perThreadRenderingContext.set(this);
    }
  }

  public Thread getRenderingThread() {
    return renderingThread;
  }

  public void setNoAutoRedrawMode(boolean noAutoRedraw) {
    this.noAutoRedraw = noAutoRedraw;
  }

  public boolean getNoAutoRedrawMode() {
    return noAutoRedraw;
  }

  /** Routine needed only for offscreen contexts in order to resize
      the underlying bitmap. Called by GLJPanel. */
  public void resizeOffscreenContext(int newWidth, int newHeight) {
    if (!isOffscreen()) {
      throw new GLException("Should only call for offscreen OpenGL contexts");
    }
    pendingOffscreenResize = true;
    pendingOffscreenWidth  = newWidth;
    pendingOffscreenHeight = newHeight;
  }

  /** Returns a non-null (but possibly empty) string containing the
      space-separated list of available platform-dependent (e.g., WGL,
      GLX) extensions. Can only be called while this context is
      current. */
  public abstract String getPlatformExtensionsString();

  /**
   * Resets the cache of which GL functions are available for calling through this
   * context. See {@link #isFunctionAvailable(String)} for more information on
   * the definition of "available".
   */
  protected void resetGLFunctionAvailability() {
    functionAvailability.flush();
    if (!haveResetGLUProcAddressTable) {
      if (DEBUG) {
        System.err.println("!!! Initializing GLU extension address table");
      }
      resetProcAddressTable(gluProcAddressTable);
      haveResetGLUProcAddressTable = true; // Only need to do this once globally
    }
  }

  /**
   * Returns true if the specified OpenGL core- or extension-function can be
   * successfully called using this GL context given the current host (OpenGL
   * <i>client</i>) and display (OpenGL <i>server</i>) configuration.
   *
   * See {@link GL#isFunctionAvailable(String)} for more details.
   *
   * @param glFunctionName the name of the OpenGL function (e.g., use
   * "glPolygonOffsetEXT" to check if the {@link
   * net.java.games.jogl.GL#glPolygonOffsetEXT(float,float)} is available).
   */
  protected boolean isFunctionAvailable(String glFunctionName) {
    return functionAvailability.isFunctionAvailable(mapToRealGLFunctionName(glFunctionName));
  }

  /**
   * Returns true if the specified OpenGL extension can be
   * successfully called using this GL context given the current host (OpenGL
   * <i>client</i>) and display (OpenGL <i>server</i>) configuration.
   *
   * See {@link GL#isExtensionAvailable(String)} for more details.
   *
   * @param glExtensionName the name of the OpenGL extension (e.g.,
   * "GL_VERTEX_PROGRAM_ARB").
   */
  public boolean isExtensionAvailable(String glExtensionName) {
    return functionAvailability.isExtensionAvailable(mapToRealGLExtensionName(glExtensionName));
  }
  
  /**
   * Pbuffer support; indicates whether this context is capable of
   * creating a subordinate pbuffer context (distinct from an
   * "offscreen context", which is typically software-rendered on all
   * platforms).
   */
  public abstract boolean canCreatePbufferContext();

  /**
   * Pbuffer support; creates a subordinate GLContext for a pbuffer
   * associated with this context.
   */
  public abstract GLContext createPbufferContext(GLCapabilities capabilities,
                                                 int initialWidth,
                                                 int initialHeight);

  /**
   * Pbuffer support; given that this is a GLContext associated with a
   * pbuffer, binds this pbuffer to its texture target.
   */
  public abstract void bindPbufferToTexture();

  /**
   * Pbuffer support; given that this is a GLContext associated with a
   * pbuffer, releases this pbuffer from its texture target.
   */
  public abstract void releasePbufferFromTexture();

  /** Maps the given "platform-independent" function name to a real function
      name. Currently this is only used to map "glAllocateMemoryNV" and
      associated routines to wglAllocateMemoryNV / glXAllocateMemoryNV. */
  protected abstract String mapToRealGLFunctionName(String glFunctionName);

  /** Maps the given "platform-independent" extension name to a real
      function name. Currently this is only used to map
      "GL_ARB_pbuffer" and "GL_ARB_pixel_format" to "WGL_ARB_pbuffer"
      and "WGL_ARB_pixel_format" (not yet mapped to X11). */
  protected abstract String mapToRealGLExtensionName(String glExtensionName);

  /** Create the GL for this context. */
  protected abstract GL createGL();
  
  /** Hook indicating whether the concrete GLContext implementation is
      offscreen and therefore whether we need to process resize
      requests. */
  protected abstract boolean isOffscreen();

  /** Only called for offscreen contexts; returns the type of
      BufferedImage required for reading this context's pixels. */
  public abstract int getOffscreenContextBufferedImageType();

  /** Only called for offscreen contexts; returns the buffer from
      which to read pixels (GL.GL_FRONT or GL.GL_BACK). */
  public abstract int getOffscreenContextReadBuffer();

  /** On some platforms the mismatch between OpenGL's coordinate
      system (origin at bottom left) and the window system's
      coordinate system (origin at top left) necessitates a vertical
      flip of pixels read from offscreen contexts. */
  public abstract boolean offscreenImageNeedsVerticalFlip();

  /** Attempts to make the GL context current. If necessary, creates a
      context and calls the initAction once the context is current.
      Most error conditions cause an exception to be thrown, except
      for the case where the context can not be created because the
      component has not yet been visualized. In this case makeCurrent
      returns false and the caller should abort any OpenGL event
      processing and instead return immediately.  */
  protected abstract boolean makeCurrent(Runnable initAction) throws GLException;

  /** Frees the OpenGL context. All error conditions cause a
      GLException to be thrown. */
  protected abstract void free() throws GLException;

  /** Swaps the buffers of the OpenGL context if necessary. All error
      conditions cause a GLException to be thrown. */
  protected abstract void swapBuffers() throws GLException;

  /** Helper routine which resets a ProcAddressTable generated by the
      GLEmitter by looking up anew all of its function pointers. */
  protected void resetProcAddressTable(Object table) {
    Class tableClass = table.getClass();
    java.lang.reflect.Field[] fields = tableClass.getDeclaredFields();
    
    for (int i = 0; i < fields.length; ++i) {
      String addressFieldName = fields[i].getName();
      if (!addressFieldName.startsWith(ProcAddressHelper.PROCADDRESS_VAR_PREFIX)) {
        // not a proc address variable
        continue;
      }
      int startOfMethodName = ProcAddressHelper.PROCADDRESS_VAR_PREFIX.length();
      String glFuncName = addressFieldName.substring(startOfMethodName);
      try {
        java.lang.reflect.Field addressField = tableClass.getDeclaredField(addressFieldName);
        assert(addressField.getType() == Long.TYPE);
        long newProcAddress = dynamicLookupFunction(glFuncName);
        // set the current value of the proc address variable in the table object
        addressField.setLong(table, newProcAddress); 
        if (DEBUG) {
          //          System.err.println(glFuncName + " = 0x" + Long.toHexString(newProcAddress));
        }
      } catch (Exception e) {
        throw new GLException("Cannot get GL proc address for method \"" +
                              glFuncName + "\": Couldn't set value of field \"" + addressFieldName +
                              "\" in class " + tableClass.getName(), e);
      }
    }
  }

  /** Dynamically looks up the given function. */
  protected abstract long dynamicLookupFunction(String glFuncName);

  /** Indicates whether the underlying OpenGL context has been
      created. This is used to manage sharing of display lists and
      textures between contexts. */
  public abstract boolean isCreated();

  /** Support for recursive makeCurrent() calls as well as calling
      other drawables' display() methods from within another one's */
  protected static GLContextStack getPerThreadContextStack() {
    return (GLContextStack) perThreadContextStack.get();
  }

  //----------------------------------------------------------------------
  // Internals only below this point
  //
  private boolean realized() {
    return ((component == null) || realized || component.isDisplayable());
  }
}