WebGLContextAttributes.java

/*
 * Copyright 2010 Google Inc.
 *
 * Licensed under the Apache License, Version 2.0 (the "License"); you may not
 * use this file except in compliance with the License. You may obtain a copy of
 * the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
 * License for the specific language governing permissions and limitations under
 * the License.
 */
package com.google.gwt.webgl.client;

import com.google.gwt.core.client.JavaScriptObject;

/**
 * The WebGLContextAttributes interface contains drawing surface attributes and
 * is passed as the second parameter to getContext. A native object may be
 * supplied as this parameter; the specified attributes will be queried from
 * this object.
 */
public class WebGLContextAttributes extends JavaScriptObject {

	public static native WebGLContextAttributes create() /*-{
															return { premultipliedAlpha:false };
															}-*/;

	protected WebGLContextAttributes() {
	}

	/**
	 * Default: true. If the value is true, the drawing buffer has an alpha
	 * channel for the purposes of performing OpenGL destination alpha
	 * operations and compositing with the page. If the value is false, no alpha
	 * buffer is available.
	 */
	public final native void setAlpha(boolean alpha) /*-{
														this.alpha = alpha;
														}-*/;

	public final native void clearAlpha() /*-{
											delete this.alpha;
											}-*/;

	/**
	 * Default: true. If the value is true, the drawing buffer has a depth
	 * buffer of at least 16 bits. If the value is false, no depth buffer is
	 * available.
	 */
	public final native void setDepth(boolean depth) /*-{
														this.depth = depth;
														}-*/;

	public final native void clearDepth() /*-{
											delete this.depth;
											}-*/;

	/**
	 * Default: false. If the value is true, the drawing buffer has a stencil
	 * buffer of at least 8 bits. If the value is false, no stencil buffer is
	 * available.
	 */
	public final native void setStencil(boolean stencil) /*-{
															this.stencil = stencil;
															}-*/;

	public final native void clearStencil() /*-{
											delete this.stencil;
											}-*/;

	/**
	 * Default: true. If the value is true and the implementation supports
	 * antialiasing the drawing buffer will perform antialiasing using its
	 * choice of technique (multisample/supersample) and quality. If the value
	 * is false or the implementation does not support antialiasing, no
	 * antialiasing is performed.
	 */
	public final native void setAntialias(boolean antialias) /*-{
																this.antialias = antialias;
																}-*/;

	public final native void clearAntialias() /*-{
												delete this.antialias;
												}-*/;

	/**
	 * Default: true. If the value is true the page compositor will assume the
	 * drawing buffer contains colors with premultiplied alpha. If the value is
	 * false the page compositor will assume that colors in the drawing buffer
	 * are not premultiplied. This flag is ignored if the alpha flag is false.
	 * See Premultiplied Alpha for more information on the effects of the
	 * premultipliedAlpha flag.
	 */
	public final native void setPremultipliedAlpha(boolean premultipliedAlpha) /*-{
																				this.premultipliedAlpha = premultipliedAlpha;
																				}-*/;

	public final native void clearPremultipliedAlpha() /*-{
														delete this.premultipliedAlpha;
														}-*/;

	public final native void setPreserveDrawingBuffer(
			boolean preserveDrawingBuffer) /*-{
											this.preserveDrawingBuffer = preserveDrawingBuffer;
											}-*/;
}