Added sharing of display lists and textures among OpenGL contexts

through new methods in GLDrawableFactory; GLContext has not been
exposed in the public API. Tested with new simple TestContextSharing
demonstration on Windows, Linux and Mac OS X.


git-svn-id: file:///usr/local/projects/SUN/JOGL/git-svn/svn-server-sync/jogl/trunk@18 232f8b59-042b-4e1e-8c03-345bb8c30851

1 files changed, 153 insertions, 0 deletions

diff --git a/src/net/java/games/jogl/impl/GLContextShareSet.java b/src/net/java/games/jogl/impl/GLContextShareSet.java
new file mode 100644
index 000000000..73ee86499
--- /dev/null
+++ b/src/net/java/games/jogl/impl/GLContextShareSet.java
@@ -0,0 +1,153 @@
+/*
+ * 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.lang.ref.*;
+import java.util.*;
+
+/** Provides a mechanism by which OpenGL contexts can share textures
+    and display lists in the face of multithreading and asynchronous
+    context creation as is inherent in the AWT and Swing. */
+
+public class GLContextShareSet {
+  // This class is implemented with a WeakHashMap that goes from the
+  // contexts as keys to a complex data structure as value that tracks
+  // context creation and deletion.
+
+  private static Map/*<GLContext, WeakReference<ShareSet>>*/ shareMap = new WeakHashMap();
+  private static Object dummyValue = new Object();
+
+  private static class ShareSet {
+    private Map allShares       = new WeakHashMap();
+    private Map createdShares   = new WeakHashMap();
+    private Map destroyedShares = new WeakHashMap();
+
+    public void add(GLContext ctx) {
+      if (allShares.put(ctx, dummyValue) == null) {
+        if (ctx.isCreated()) {
+          createdShares.put(ctx, dummyValue);
+        } else {
+          destroyedShares.put(ctx, dummyValue);
+        }
+      }      
+    }
+
+    public GLContext getCreatedShare(GLContext ignore) {
+      for (Iterator iter = createdShares.keySet().iterator(); iter.hasNext(); ) {
+        GLContext ctx = (GLContext) iter.next();
+        if (ctx != ignore) {
+          return ctx;
+        }
+      }
+      return null;
+    }
+
+    public void contextCreated(GLContext ctx) {
+      Object res = destroyedShares.remove(ctx);
+      assert res != null : "State of ShareSet corrupted; thought context " +
+        ctx + " should have been in destroyed set but wasn't";
+      res = createdShares.put(ctx, dummyValue);
+      assert res == null : "State of ShareSet corrupted; thought context " +
+        ctx + " shouldn't have been in created set but was";
+    }
+
+    public void contextDestroyed(GLContext ctx) {
+      Object res = createdShares.remove(ctx);
+      assert res != null : "State of ShareSet corrupted; thought context " +
+        ctx + " should have been in created set but wasn't";
+      res = destroyedShares.put(ctx, dummyValue);
+      assert res == null : "State of ShareSet corrupted; thought context " +
+        ctx + " shouldn't have been in destroyed set but was";
+    }
+  }
+
+
+  /** Indicate that contexts <code>share1</code> and
+      <code>share2</code> will share textures and display lists. */
+  public static synchronized void registerSharing(GLContext share1, GLContext share2) {
+    ShareSet share = entryFor(share1);
+    if (share == null) {
+      share = entryFor(share2);
+    }
+    if (share == null) {
+      share = new ShareSet();
+    }
+    share.add(share1);
+    share.add(share2);
+    addEntry(share1, share);
+    addEntry(share2, share);
+  }
+
+  public static synchronized GLContext getShareContext(GLContext contextToCreate) {
+    ShareSet share = entryFor(contextToCreate);
+    if (share == null) {
+      return null;
+    }
+    return share.getCreatedShare(contextToCreate);
+  }
+
+  public static synchronized void contextCreated(GLContext context) {
+    ShareSet share = entryFor(context);
+    if (share != null) {
+      share.contextCreated(context);
+    }
+  }
+
+  public static synchronized void contextDestroyed(GLContext context) {
+    ShareSet share = entryFor(context);
+    if (share != null) {
+      share.contextDestroyed(context);
+    }
+  }
+
+  //----------------------------------------------------------------------
+  // Internals only below this point
+  //
+
+  private static ShareSet entryFor(GLContext context) {
+    return (ShareSet) shareMap.get(context);
+  }
+
+  private static void addEntry(GLContext context, ShareSet share) {
+    if (shareMap.get(context) == null) {
+      shareMap.put(context, share);
+    }
+  }
+}