bundles/org.eclipse.swt/Eclipse SWT OpenGL/gtk/org/eclipse/swt/opengl/GLCanvas.java - platform/eclipse.platform.swt - Git at Google

 /*******************************************************************************
  * Copyright (c) 2000, 2005 IBM Corporation and others.
  * All rights reserved. This program and the accompanying materials
  * are made available under the terms of the Eclipse Public License v1.0
  * which accompanies this distribution, and is available at
  * http://www.eclipse.org/legal/epl-v10.html
  *
  * Contributors:
  *     IBM Corporation - initial API and implementation
  *******************************************************************************/
 package org.eclipse.swt.opengl;

 import org.eclipse.swt.*;
 import org.eclipse.swt.widgets.*;
 import org.eclipse.swt.graphics.*;
 import org.eclipse.swt.internal.gtk.*;
 import org.eclipse.swt.internal.opengl.glx.*;

 /**
  * GLCanvas is a widget capable of displaying OpenGL content.
  *
  * WARNING API STILL UNDER CONSTRUCTION AND SUBJECT TO CHANGE
  *
  * @since 3.2
  */

 public class GLCanvas extends Canvas {
 	int /*long*/ context;
 	int /*long*/ xWindow;
 	int /*long*/ glWindow;
 	XVisualInfo vinfo;
 	static final int MAX_ATTRIBUTES = 32;

 /**
  * Create a GLCanvas widget using the attributes described in the GLData
  * object provided.
  *
  * @param parent a composite widget
  * @param style the bitwise OR'ing of widget styles
  * @param data the requested attributes of the GLCanvas
  *
  * @exception IllegalArgumentException
  * <ul><li>ERROR_NULL_ARGUMENT when the data is null
  *     <li>ERROR_UNSUPPORTED_DEPTH when the requested attributes cannot be provided</ul>
  * </ul>
  *
  * WARNING API STILL UNDER CONSTRUCTION AND SUBJECT TO CHANGE
  *
  * @since 3.2
  */
 public GLCanvas (Composite parent, int style, GLData data) {
 	super (parent, style);
 	if (data == null) SWT.error (SWT.ERROR_NULL_ARGUMENT);
 	int glxAttrib [] = new int [MAX_ATTRIBUTES];
 	int pos = 0;
 	glxAttrib [pos++] = GLX.GLX_RGBA;
 	if (data.doubleBuffer) glxAttrib [pos++] = GLX.GLX_DOUBLEBUFFER;
 	if (data.stereo) glxAttrib [pos++] = GLX.GLX_STEREO;
 	if (data.redSize > 0) {
 		glxAttrib [pos++] = GLX.GLX_RED_SIZE;
 		glxAttrib [pos++] = data.redSize;
 	}
 	if (data.greenSize > 0) {
 		glxAttrib [pos++] = GLX.GLX_GREEN_SIZE;
 		glxAttrib [pos++] = data.greenSize;
 	}
 	if (data.blueSize > 0) {
 		glxAttrib [pos++] = GLX.GLX_BLUE_SIZE;
 		glxAttrib [pos++] = data.blueSize;
 	}
 	if (data.alphaSize > 0) {
 		glxAttrib [pos++] = GLX.GLX_ALPHA_SIZE;
 		glxAttrib [pos++] = data.alphaSize;
 	}
 	if (data.depthSize > 0) {
 		glxAttrib [pos++] = GLX.GLX_DEPTH_SIZE;
 		glxAttrib [pos++] = data.depthSize;
 	}
 	if (data.stencilSize > 0) {
 		glxAttrib [pos++] = GLX.GLX_STENCIL_SIZE;
 		glxAttrib [pos++] = data.stencilSize;
 	}
 	if (data.accumRedSize > 0) {
 		glxAttrib [pos++] = GLX.GLX_ACCUM_RED_SIZE;
 		glxAttrib [pos++] = data.accumRedSize;
 	}
 	if (data.accumGreenSize > 0) {
 		glxAttrib [pos++] = GLX.GLX_ACCUM_GREEN_SIZE;
 		glxAttrib [pos++] = data.accumGreenSize;
 	}
 	if (data.accumBlueSize > 0) {
 		glxAttrib [pos++] = GLX.GLX_ACCUM_BLUE_SIZE;
 		glxAttrib [pos++] = data.accumBlueSize;
 	}
 	if (data.accumAlphaSize > 0) {
 		glxAttrib [pos++] = GLX.GLX_ACCUM_ALPHA_SIZE;
 		glxAttrib [pos++] = data.accumAlphaSize;
 	}
 	if (data.sampleBuffers > 0) {
 		glxAttrib [pos++] = GLX.GLX_SAMPLE_BUFFERS;
 		glxAttrib [pos++] = data.sampleBuffers;
 	}
 	if (data.samples > 0) {
 		glxAttrib [pos++] = GLX.GLX_SAMPLES;
 		glxAttrib [pos++] = data.samples;
 	}
 	glxAttrib [pos++] = 0;
 	OS.gtk_widget_realize (handle);
 	int /*long*/ window = OS.GTK_WIDGET_WINDOW (handle);
 	int /*long*/ xDisplay = OS.gdk_x11_drawable_get_xdisplay (window);
 	int /*long*/ infoPtr = GLX.glXChooseVisual (xDisplay, OS.XDefaultScreen (xDisplay), glxAttrib);
 	if (infoPtr == 0) {
 		dispose ();
 		SWT.error (SWT.ERROR_UNSUPPORTED_DEPTH);
 	}
 	vinfo = new XVisualInfo ();
 	GLX.memmove (vinfo, infoPtr, XVisualInfo.sizeof);
 	OS.XFree (infoPtr);
 	int /*long*/ screen = OS.gdk_screen_get_default ();
 	int /*long*/ gdkvisual = OS.gdk_x11_screen_lookup_visual (screen, vinfo.visualid);
 	//FIXME- share lists
 	//context = GLX.glXCreateContext (xDisplay, info, share == null ? 0 : share.context, true);
 	context = GLX.glXCreateContext (xDisplay, vinfo, 0, true);
 	if (context == 0) SWT.error (SWT.ERROR_NO_HANDLES);
 	GdkWindowAttr attrs = new GdkWindowAttr ();
 	attrs.width = 1;
 	attrs.height = 1;
 	attrs.event_mask = OS.GDK_KEY_PRESS_MASK | OS.GDK_KEY_RELEASE_MASK |
 		OS.GDK_FOCUS_CHANGE_MASK | OS.GDK_POINTER_MOTION_MASK |
 		OS.GDK_BUTTON_PRESS_MASK | OS.GDK_BUTTON_RELEASE_MASK |
 		OS.GDK_ENTER_NOTIFY_MASK | OS.GDK_LEAVE_NOTIFY_MASK |
 		OS.GDK_EXPOSURE_MASK | OS.GDK_VISIBILITY_NOTIFY_MASK |
 		OS.GDK_POINTER_MOTION_HINT_MASK;
 	attrs.window_type = OS.GDK_WINDOW_CHILD;
 	attrs.visual = gdkvisual;
 	glWindow = OS.gdk_window_new (window, attrs, OS.GDK_WA_VISUAL);
 	OS.gdk_window_set_user_data (glWindow, handle);
 	if ((style & SWT.NO_BACKGROUND) != 0) OS.gdk_window_set_back_pixmap (window, 0, false);
 	xWindow = OS.gdk_x11_drawable_get_xid (glWindow);
 	OS.gdk_window_show (glWindow);

 	Listener listener = new Listener () {
 		public void handleEvent (Event event) {
 			switch (event.type) {
 			case SWT.Paint:
 				/**
 				* Bug in MESA.  MESA does some nasty sort of polling to try
 				* and ensure that their buffer sizes match the current X state.
 				* This state can be updated using glViewport().
 				* FIXME: There has to be a better way of doing this.
 				*/
 				int [] viewport = new int [4];
 				GLX.glGetIntegerv (GLX.GL_VIEWPORT, viewport);
 				GLX.glViewport (viewport [0],viewport [1],viewport [2],viewport [3]);
 				break;
 			case SWT.Resize:
 				Rectangle clientArea = getClientArea();
 				OS.gdk_window_move (glWindow, clientArea.x, clientArea.y);
 				OS.gdk_window_resize (glWindow, clientArea.width, clientArea.height);
 				break;
 			case SWT.Dispose:
 				int /*long*/ window = OS.GTK_WIDGET_WINDOW (handle);
 				int /*long*/ xDisplay = OS.gdk_x11_drawable_get_xdisplay (window);
 				if (context != 0) {
 					if (GLX.glXGetCurrentContext () == context) {
 						GLX.glXMakeCurrent (xDisplay, 0, 0);
 					}
 					GLX.glXDestroyContext (xDisplay, context);
 					context = 0;
 				}
 				if (glWindow != 0) {
 					OS.gdk_window_destroy (glWindow);
 					glWindow = 0;
 				}
 				break;
 			}
 		}
 	};
 	addListener (SWT.Resize, listener);
 	addListener (SWT.Paint, listener);
 	addListener (SWT.Dispose, listener);
 }

 /**
  * Returns a GLData object describing the created context.
  *
  * @return GLData description of the OpenGL context attributes
  * @exception SWTException <ul>
  *    <li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed</li>
  *    <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li>
  * </ul>
  *
  * WARNING API STILL UNDER CONSTRUCTION AND SUBJECT TO CHANGE
  *
  * @since 3.2
  */
 public GLData getGLData () {
 	checkWidget ();
 	int /*long*/ window = OS.GTK_WIDGET_WINDOW (handle);
 	int /*long*/ xDisplay = OS.gdk_x11_drawable_get_xdisplay (window);
 	GLData data = new GLData ();
 	int [] value = new int [1];
 	GLX.glXGetConfig (xDisplay, vinfo, GLX.GLX_DOUBLEBUFFER, value);
 	data.doubleBuffer = value [0] != 0;
 	GLX.glXGetConfig (xDisplay, vinfo, GLX.GLX_STEREO, value);
 	data.stereo = value [0] != 0;
 	GLX.glXGetConfig (xDisplay, vinfo, GLX.GLX_RED_SIZE, value);
 	data.redSize = value [0];
 	GLX.glXGetConfig (xDisplay, vinfo, GLX.GLX_GREEN_SIZE, value);
 	data.greenSize = value [0];
 	GLX.glXGetConfig (xDisplay, vinfo, GLX.GLX_BLUE_SIZE, value);
 	data.blueSize = value [0];
 	GLX.glXGetConfig (xDisplay, vinfo, GLX.GLX_ALPHA_SIZE, value);
 	data.alphaSize = value [0];
 	GLX.glXGetConfig (xDisplay, vinfo, GLX.GLX_DEPTH_SIZE, value);
 	data.depthSize = value [0];
 	GLX.glXGetConfig (xDisplay, vinfo, GLX.GLX_STENCIL_SIZE, value);
 	data.stencilSize = value [0];
 	GLX.glXGetConfig (xDisplay, vinfo, GLX.GLX_ACCUM_RED_SIZE, value);
 	data.accumRedSize = value [0];
 	GLX.glXGetConfig (xDisplay, vinfo, GLX.GLX_ACCUM_GREEN_SIZE, value);
 	data.accumGreenSize = value [0];
 	GLX.glXGetConfig (xDisplay, vinfo, GLX.GLX_ACCUM_BLUE_SIZE, value);
 	data.accumBlueSize = value [0];
 	GLX.glXGetConfig (xDisplay, vinfo, GLX.GLX_ACCUM_ALPHA_SIZE, value);
 	data.accumAlphaSize = value [0];
 	GLX.glXGetConfig (xDisplay, vinfo, GLX.GLX_SAMPLE_BUFFERS, value);
 	data.sampleBuffers = value [0];
 	GLX.glXGetConfig (xDisplay, vinfo, GLX.GLX_SAMPLES, value);
 	data.samples = value [0];
 	return data;
 }

 /**
  * Returns a boolean indicating whether the receiver's OpenGL context
  * is the current context.
  *
  * @return true if the receiver holds the current OpenGL context,
  * false otherwise
  * @exception SWTException <ul>
  *    <li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed</li>
  *    <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li>
  * </ul>
  *
  * WARNING API STILL UNDER CONSTRUCTION AND SUBJECT TO CHANGE
  *
  * @since 3.2
  */
 public boolean isCurrent () {
 	checkWidget ();
 	return GLX.glXGetCurrentContext () == context;
 }

 /**
  * Sets the OpenGL context associated with this GLCanvas to be the
  * current GL context.
  *
  * @exception SWTException <ul>
  *    <li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed</li>
  *    <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li>
  * </ul>
  *
  * WARNING API STILL UNDER CONSTRUCTION AND SUBJECT TO CHANGE
  *
  * @since 3.2
  */
 public void setCurrent () {
 	checkWidget ();
 	if (GLX.glXGetCurrentContext () == context) return;
 	int /*long*/ window = OS.GTK_WIDGET_WINDOW (handle);
 	int /*long*/ xDisplay = OS.gdk_x11_drawable_get_xdisplay (window);
 	GLX.glXMakeCurrent (xDisplay, xWindow, context);
 }

 /**
  * Swaps the front and back color buffers.
  *
  * @exception SWTException <ul>
  *    <li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed</li>
  *    <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li>
  * </ul>
  *
  * WARNING API STILL UNDER CONSTRUCTION AND SUBJECT TO CHANGE
  *
  * @since 3.2
  */
 public void swapBuffers () {
 	checkWidget ();
 	int /*long*/ window = OS.GTK_WIDGET_WINDOW (handle);
 	int /*long*/ xDisplay = OS.gdk_x11_drawable_get_xdisplay (window);
 	GLX.glXSwapBuffers (xDisplay, xWindow);
 }
 }
	/*******************************************************************************
	* Copyright (c) 2000, 2005 IBM Corporation and others.
	* All rights reserved. This program and the accompanying materials
	* are made available under the terms of the Eclipse Public License v1.0
	* which accompanies this distribution, and is available at
	* http://www.eclipse.org/legal/epl-v10.html
	*
	* Contributors:
	* IBM Corporation - initial API and implementation
	*******************************************************************************/
	package org.eclipse.swt.opengl;

	import org.eclipse.swt.*;
	import org.eclipse.swt.widgets.*;
	import org.eclipse.swt.graphics.*;
	import org.eclipse.swt.internal.gtk.*;
	import org.eclipse.swt.internal.opengl.glx.*;

	/**
	* GLCanvas is a widget capable of displaying OpenGL content.
	*
	* WARNING API STILL UNDER CONSTRUCTION AND SUBJECT TO CHANGE
	*
	* @since 3.2
	*/

	public class GLCanvas extends Canvas {
	int /long/ context;
	int /long/ xWindow;
	int /long/ glWindow;
	XVisualInfo vinfo;
	static final int MAX_ATTRIBUTES = 32;

	/**
	* Create a GLCanvas widget using the attributes described in the GLData
	* object provided.
	*
	* @param parent a composite widget
	* @param style the bitwise OR'ing of widget styles
	* @param data the requested attributes of the GLCanvas
	*
	* @exception IllegalArgumentException
	* <ul><li>ERROR_NULL_ARGUMENT when the data is null
	* <li>ERROR_UNSUPPORTED_DEPTH when the requested attributes cannot be provided</ul>
	* </ul>
	*
	* WARNING API STILL UNDER CONSTRUCTION AND SUBJECT TO CHANGE
	*
	* @since 3.2
	*/
	public GLCanvas (Composite parent, int style, GLData data) {
	super (parent, style);
	if (data == null) SWT.error (SWT.ERROR_NULL_ARGUMENT);
	int glxAttrib [] = new int [MAX_ATTRIBUTES];
	int pos = 0;
	glxAttrib [pos++] = GLX.GLX_RGBA;
	if (data.doubleBuffer) glxAttrib [pos++] = GLX.GLX_DOUBLEBUFFER;
	if (data.stereo) glxAttrib [pos++] = GLX.GLX_STEREO;
	if (data.redSize > 0) {
	glxAttrib [pos++] = GLX.GLX_RED_SIZE;
	glxAttrib [pos++] = data.redSize;
	}
	if (data.greenSize > 0) {
	glxAttrib [pos++] = GLX.GLX_GREEN_SIZE;
	glxAttrib [pos++] = data.greenSize;
	}
	if (data.blueSize > 0) {
	glxAttrib [pos++] = GLX.GLX_BLUE_SIZE;
	glxAttrib [pos++] = data.blueSize;
	}
	if (data.alphaSize > 0) {
	glxAttrib [pos++] = GLX.GLX_ALPHA_SIZE;
	glxAttrib [pos++] = data.alphaSize;
	}
	if (data.depthSize > 0) {
	glxAttrib [pos++] = GLX.GLX_DEPTH_SIZE;
	glxAttrib [pos++] = data.depthSize;
	}
	if (data.stencilSize > 0) {
	glxAttrib [pos++] = GLX.GLX_STENCIL_SIZE;
	glxAttrib [pos++] = data.stencilSize;
	}
	if (data.accumRedSize > 0) {
	glxAttrib [pos++] = GLX.GLX_ACCUM_RED_SIZE;
	glxAttrib [pos++] = data.accumRedSize;
	}
	if (data.accumGreenSize > 0) {
	glxAttrib [pos++] = GLX.GLX_ACCUM_GREEN_SIZE;
	glxAttrib [pos++] = data.accumGreenSize;
	}
	if (data.accumBlueSize > 0) {
	glxAttrib [pos++] = GLX.GLX_ACCUM_BLUE_SIZE;
	glxAttrib [pos++] = data.accumBlueSize;
	}
	if (data.accumAlphaSize > 0) {
	glxAttrib [pos++] = GLX.GLX_ACCUM_ALPHA_SIZE;
	glxAttrib [pos++] = data.accumAlphaSize;
	}
	if (data.sampleBuffers > 0) {
	glxAttrib [pos++] = GLX.GLX_SAMPLE_BUFFERS;
	glxAttrib [pos++] = data.sampleBuffers;
	}
	if (data.samples > 0) {
	glxAttrib [pos++] = GLX.GLX_SAMPLES;
	glxAttrib [pos++] = data.samples;
	}
	glxAttrib [pos++] = 0;
	OS.gtk_widget_realize (handle);
	int /long/ window = OS.GTK_WIDGET_WINDOW (handle);
	int /long/ xDisplay = OS.gdk_x11_drawable_get_xdisplay (window);
	int /long/ infoPtr = GLX.glXChooseVisual (xDisplay, OS.XDefaultScreen (xDisplay), glxAttrib);
	if (infoPtr == 0) {
	dispose ();
	SWT.error (SWT.ERROR_UNSUPPORTED_DEPTH);
	}
	vinfo = new XVisualInfo ();
	GLX.memmove (vinfo, infoPtr, XVisualInfo.sizeof);
	OS.XFree (infoPtr);
	int /long/ screen = OS.gdk_screen_get_default ();
	int /long/ gdkvisual = OS.gdk_x11_screen_lookup_visual (screen, vinfo.visualid);
	//FIXME- share lists
	//context = GLX.glXCreateContext (xDisplay, info, share == null ? 0 : share.context, true);
	context = GLX.glXCreateContext (xDisplay, vinfo, 0, true);
	if (context == 0) SWT.error (SWT.ERROR_NO_HANDLES);
	GdkWindowAttr attrs = new GdkWindowAttr ();
	attrs.width = 1;
	attrs.height = 1;
	attrs.event_mask = OS.GDK_KEY_PRESS_MASK \| OS.GDK_KEY_RELEASE_MASK \|
	OS.GDK_FOCUS_CHANGE_MASK \| OS.GDK_POINTER_MOTION_MASK \|
	OS.GDK_BUTTON_PRESS_MASK \| OS.GDK_BUTTON_RELEASE_MASK \|
	OS.GDK_ENTER_NOTIFY_MASK \| OS.GDK_LEAVE_NOTIFY_MASK \|
	OS.GDK_EXPOSURE_MASK \| OS.GDK_VISIBILITY_NOTIFY_MASK \|
	OS.GDK_POINTER_MOTION_HINT_MASK;
	attrs.window_type = OS.GDK_WINDOW_CHILD;
	attrs.visual = gdkvisual;
	glWindow = OS.gdk_window_new (window, attrs, OS.GDK_WA_VISUAL);
	OS.gdk_window_set_user_data (glWindow, handle);
	if ((style & SWT.NO_BACKGROUND) != 0) OS.gdk_window_set_back_pixmap (window, 0, false);
	xWindow = OS.gdk_x11_drawable_get_xid (glWindow);
	OS.gdk_window_show (glWindow);

	Listener listener = new Listener () {
	public void handleEvent (Event event) {
	switch (event.type) {
	case SWT.Paint:
	/**
	* Bug in MESA. MESA does some nasty sort of polling to try
	* and ensure that their buffer sizes match the current X state.
	* This state can be updated using glViewport().
	* FIXME: There has to be a better way of doing this.
	*/
	int [] viewport = new int [4];
	GLX.glGetIntegerv (GLX.GL_VIEWPORT, viewport);
	GLX.glViewport (viewport [0],viewport [1],viewport [2],viewport [3]);
	break;
	case SWT.Resize:
	Rectangle clientArea = getClientArea();
	OS.gdk_window_move (glWindow, clientArea.x, clientArea.y);
	OS.gdk_window_resize (glWindow, clientArea.width, clientArea.height);
	break;
	case SWT.Dispose:
	int /long/ window = OS.GTK_WIDGET_WINDOW (handle);
	int /long/ xDisplay = OS.gdk_x11_drawable_get_xdisplay (window);
	if (context != 0) {
	if (GLX.glXGetCurrentContext () == context) {
	GLX.glXMakeCurrent (xDisplay, 0, 0);
	}
	GLX.glXDestroyContext (xDisplay, context);
	context = 0;
	}
	if (glWindow != 0) {
	OS.gdk_window_destroy (glWindow);
	glWindow = 0;
	}
	break;
	}
	}
	};
	addListener (SWT.Resize, listener);
	addListener (SWT.Paint, listener);
	addListener (SWT.Dispose, listener);
	}

	/**
	* Returns a GLData object describing the created context.
	*
	* @return GLData description of the OpenGL context attributes
	* @exception SWTException <ul>
	* <li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed</li>
	* <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li>
	* </ul>
	*
	* WARNING API STILL UNDER CONSTRUCTION AND SUBJECT TO CHANGE
	*
	* @since 3.2
	*/
	public GLData getGLData () {
	checkWidget ();
	int /long/ window = OS.GTK_WIDGET_WINDOW (handle);
	int /long/ xDisplay = OS.gdk_x11_drawable_get_xdisplay (window);
	GLData data = new GLData ();
	int [] value = new int [1];
	GLX.glXGetConfig (xDisplay, vinfo, GLX.GLX_DOUBLEBUFFER, value);
	data.doubleBuffer = value [0] != 0;
	GLX.glXGetConfig (xDisplay, vinfo, GLX.GLX_STEREO, value);
	data.stereo = value [0] != 0;
	GLX.glXGetConfig (xDisplay, vinfo, GLX.GLX_RED_SIZE, value);
	data.redSize = value [0];
	GLX.glXGetConfig (xDisplay, vinfo, GLX.GLX_GREEN_SIZE, value);
	data.greenSize = value [0];
	GLX.glXGetConfig (xDisplay, vinfo, GLX.GLX_BLUE_SIZE, value);
	data.blueSize = value [0];
	GLX.glXGetConfig (xDisplay, vinfo, GLX.GLX_ALPHA_SIZE, value);
	data.alphaSize = value [0];
	GLX.glXGetConfig (xDisplay, vinfo, GLX.GLX_DEPTH_SIZE, value);
	data.depthSize = value [0];
	GLX.glXGetConfig (xDisplay, vinfo, GLX.GLX_STENCIL_SIZE, value);
	data.stencilSize = value [0];
	GLX.glXGetConfig (xDisplay, vinfo, GLX.GLX_ACCUM_RED_SIZE, value);
	data.accumRedSize = value [0];
	GLX.glXGetConfig (xDisplay, vinfo, GLX.GLX_ACCUM_GREEN_SIZE, value);
	data.accumGreenSize = value [0];
	GLX.glXGetConfig (xDisplay, vinfo, GLX.GLX_ACCUM_BLUE_SIZE, value);
	data.accumBlueSize = value [0];
	GLX.glXGetConfig (xDisplay, vinfo, GLX.GLX_ACCUM_ALPHA_SIZE, value);
	data.accumAlphaSize = value [0];
	GLX.glXGetConfig (xDisplay, vinfo, GLX.GLX_SAMPLE_BUFFERS, value);
	data.sampleBuffers = value [0];
	GLX.glXGetConfig (xDisplay, vinfo, GLX.GLX_SAMPLES, value);
	data.samples = value [0];
	return data;
	}

	/**
	* Returns a boolean indicating whether the receiver's OpenGL context
	* is the current context.
	*
	* @return true if the receiver holds the current OpenGL context,
	* false otherwise
	* @exception SWTException <ul>
	* <li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed</li>
	* <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li>
	* </ul>
	*
	* WARNING API STILL UNDER CONSTRUCTION AND SUBJECT TO CHANGE
	*
	* @since 3.2
	*/
	public boolean isCurrent () {
	checkWidget ();
	return GLX.glXGetCurrentContext () == context;
	}

	/**
	* Sets the OpenGL context associated with this GLCanvas to be the
	* current GL context.
	*
	* @exception SWTException <ul>
	* <li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed</li>
	* <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li>
	* </ul>
	*
	* WARNING API STILL UNDER CONSTRUCTION AND SUBJECT TO CHANGE
	*
	* @since 3.2
	*/
	public void setCurrent () {
	checkWidget ();
	if (GLX.glXGetCurrentContext () == context) return;
	int /long/ window = OS.GTK_WIDGET_WINDOW (handle);
	int /long/ xDisplay = OS.gdk_x11_drawable_get_xdisplay (window);
	GLX.glXMakeCurrent (xDisplay, xWindow, context);
	}

	/**
	* Swaps the front and back color buffers.
	*
	* @exception SWTException <ul>
	* <li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed</li>
	* <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li>
	* </ul>
	*
	* WARNING API STILL UNDER CONSTRUCTION AND SUBJECT TO CHANGE
	*
	* @since 3.2
	*/
	public void swapBuffers () {
	checkWidget ();
	int /long/ window = OS.GTK_WIDGET_WINDOW (handle);
	int /long/ xDisplay = OS.gdk_x11_drawable_get_xdisplay (window);
	GLX.glXSwapBuffers (xDisplay, xWindow);
	}
	}