/*******************************************************************************
* Copyright (c) 2000, 2009 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.internal.cocoa.*;
import org.eclipse.swt.opengl.GLData;
/**
* GLCanvas is a widget capable of displaying OpenGL content.
*
* @see GLData
* @see <a href="http://www.eclipse.org/swt/snippets/#opengl">OpenGL snippets</a>
* @see <a href="http://www.eclipse.org/swt/">Sample code and further information</a>
*
* @since 3.2
*/
public class GLCanvas extends Canvas {
NSOpenGLContext context;
NSOpenGLPixelFormat pixelFormat;
static final int MAX_ATTRIBUTES = 32;
static final String GLCONTEXT_KEY = "org.eclipse.swt.internal.cocoa.glcontext"; //$NON-NLS-1$
/**
* 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>
*/
public GLCanvas (Composite parent, int style, GLData data) {
super (parent, style);
if (data == null) SWT.error (SWT.ERROR_NULL_ARGUMENT);
int attrib [] = new int [MAX_ATTRIBUTES];
int pos = 0;
if (data.doubleBuffer) attrib [pos++] = OS.NSOpenGLPFADoubleBuffer;
if (data.stereo) attrib [pos++] = OS.NSOpenGLPFAStereo;
/*
* Feature in Cocoa: NSOpenGL/CoreOpenGL only supports specifying the total number of bits
* in the size of the color component. If specified, the color size is the sum of the red, green
* and blue values in the GLData.
*/
if ((data.redSize + data.blueSize + data.greenSize) > 0) {
attrib [pos++] = OS.NSOpenGLPFAColorSize;
attrib [pos++] = data.redSize + data.greenSize + data.blueSize;
}
if (data.alphaSize > 0) {
attrib [pos++] = OS.NSOpenGLPFAAlphaSize;
attrib [pos++] = data.alphaSize;
}
if (data.depthSize > 0) {
attrib [pos++] = OS.NSOpenGLPFADepthSize;
attrib [pos++] = data.depthSize;
}
if (data.stencilSize > 0) {
attrib [pos++] = OS.NSOpenGLPFAStencilSize;
attrib [pos++] = data.stencilSize;
}
/*
* Feature in Cocoa: NSOpenGL/CoreOpenGL only supports specifying the total number of bits
* in the size of the color accumulator component. If specified, the color size is the sum of the red, green,
* blue and alpha accum values in the GLData.
*/
if ((data.accumRedSize + data.accumBlueSize + data.accumGreenSize) > 0) {
attrib [pos++] = OS.NSOpenGLPFAAccumSize;
attrib [pos++] = data.accumRedSize + data.accumGreenSize + data.accumBlueSize + data.accumAlphaSize;
}
if (data.sampleBuffers > 0) {
attrib [pos++] = OS.NSOpenGLPFASampleBuffers;
attrib [pos++] = data.sampleBuffers;
}
if (data.samples > 0) {
attrib [pos++] = OS.NSOpenGLPFASamples;
attrib [pos++] = data.samples;
}
attrib [pos++] = 0;
pixelFormat = (NSOpenGLPixelFormat)new NSOpenGLPixelFormat().alloc();
if (pixelFormat == null) {
dispose ();
SWT.error (SWT.ERROR_UNSUPPORTED_DEPTH);
}
pixelFormat.initWithAttributes(attrib);
NSOpenGLContext ctx = data.shareContext != null ? data.shareContext.context : null;
context = (NSOpenGLContext) new NSOpenGLContext().alloc();
if (context == null) {
dispose ();
SWT.error (SWT.ERROR_UNSUPPORTED_DEPTH);
}
context = context.initWithFormat(pixelFormat, ctx);
context.setValues(new int[]{-1}, OS.NSOpenGLCPSurfaceOrder);
setData(GLCONTEXT_KEY, context);
NSNotificationCenter.defaultCenter().addObserver(view, OS.sel_updateOpenGLContext_, OS.NSViewGlobalFrameDidChangeNotification, view);
Listener listener = new Listener () {
public void handleEvent (Event event) {
switch (event.type) {
case SWT.Dispose:
setData(GLCONTEXT_KEY, null);
NSNotificationCenter.defaultCenter().removeObserver(view);
if (context != null) {
context.clearDrawable();
context.release();
}
context = null;
if (pixelFormat != null) pixelFormat.release();
pixelFormat = null;
break;
}
}
};
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>
*/
public GLData getGLData () {
checkWidget ();
GLData data = new GLData ();
long /*int*/ [] value = new long /*int*/ [1];
pixelFormat.getValues(value, OS.NSOpenGLPFADoubleBuffer, 0);
data.doubleBuffer = value [0] != 0;
pixelFormat.getValues(value, OS.NSOpenGLPFAStereo, 0);
data.stereo = value [0] != 0;
pixelFormat.getValues(value, OS.NSOpenGLPFAAlphaSize, 0);
data.alphaSize = (int/*64*/)value [0];
/*
* Feature in Cocoa: NSOpenGL/CoreOpenGL only supports specifying the total number of bits
* in the size of the color component. For compatibility we split the color size less any alpha
* into thirds and allocate a third to each color.
*/
pixelFormat.getValues(value, OS.NSOpenGLPFAColorSize, 0);
int colorSize = ((int/*64*/)(value[0] - data.alphaSize)) / 3;
data.redSize = colorSize;
data.greenSize = colorSize;
data.blueSize = colorSize;
pixelFormat.getValues(value, OS.NSOpenGLPFADepthSize, 0);
data.depthSize = (int/*64*/)value [0];
pixelFormat.getValues(value, OS.NSOpenGLPFAStencilSize, 0);
data.stencilSize = (int/*64*/)value [0];
/*
* Feature(?) in Cocoa: NSOpenGL/CoreOpenGL doesn't support setting an accumulation buffer alpha, but
* has an alpha if the color values for the accumulation buffer were set. Allocate the values evenly
* in that case.
*/
pixelFormat.getValues(value, OS.NSOpenGLPFAAccumSize, 0);
int accumColorSize = (int/*64*/)(value[0]) / 4;
data.accumRedSize = accumColorSize;
data.accumGreenSize = accumColorSize;
data.accumBlueSize = accumColorSize;
data.accumAlphaSize = accumColorSize;
pixelFormat.getValues(value, OS.NSOpenGLPFASampleBuffers, 0);
data.sampleBuffers = (int/*64*/)value [0];
pixelFormat.getValues(value, OS.NSOpenGLPFASamples, 0);
data.samples = (int/*64*/)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>
*/
public boolean isCurrent () {
checkWidget ();
NSOpenGLContext current = NSOpenGLContext.currentContext();
return current != null && current.id == context.id;
}
/**
* 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>
*/
public void setCurrent () {
checkWidget ();
context.makeCurrentContext();
}
/**
* 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>
*/
public void swapBuffers () {
checkWidget ();
context.flushBuffer();
}
}