/*******************************************************************************
* Copyright (c) 2015 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
* EclipseSource - ongoing development
*******************************************************************************/
package org.eclipse.swt.graphics;
import org.eclipse.swt.SWT;
import org.eclipse.swt.internal.SerializableCompatibility;
/**
* Instances of this class are descriptions of colors in
* terms of the primary additive color model (red, green, blue
* and alpha). A color may be described in terms of the relative
* intensities of these three primary colors. The brightness
* of each color is specified by a value in the range 0 to 255,
* where 0 indicates no color (blackness) and 255 indicates
* maximum intensity and for alpha 0 indicates transparent and
* 255 indicates opaque.
* <p>
* The hashCode() method in this class uses the values of the public
* fields to compute the hash value. When storing instances of the
* class in hashed collections, do not modify these fields after the
* object has been inserted.
* </p>
* <p>
* Application code does <em>not</em> need to explicitly release the
* resources managed by each instance when those instances are no longer
* required, and thus no <code>dispose()</code> method is provided.
* </p>
*
* @see Color
*
* @since 3.1
*/
public final class RGBA implements SerializableCompatibility {
/**
* the RGB component of the RGBA
*/
public final RGB rgb;
/**
* the alpha component of the RGBA
*/
public int alpha;
/**
* Constructs an instance of this class with the given
* red, green, blue and alpha values.
*
* @param red the red component of the new instance
* @param green the green component of the new instance
* @param blue the blue component of the new instance
* @param alpha the alpha component of the new instance
*
* @exception IllegalArgumentException <ul>
* <li>ERROR_INVALID_ARGUMENT - if the red, green, blue or alpha argument is not between 0 and 255</li>
* </ul>
*/
public RGBA( int red, int green, int blue, int alpha ) {
if( alpha > 255 || alpha < 0 ) {
SWT.error( SWT.ERROR_INVALID_ARGUMENT );
}
this.rgb = new RGB( red, green, blue );
this.alpha = alpha;
}
/**
* Constructs an instance of this class with the given
* hue, saturation, and brightness.
*
* @param hue the hue value for the HSBA color (from 0 to 360)
* @param saturation the saturation value for the HSBA color (from 0 to 1)
* @param brightness the brightness value for the HSBA color (from 0 to 1)
* @param alpha the alpha value for the HSBA color (from 0 to 255)
*
* @exception IllegalArgumentException <ul>
* <li>ERROR_INVALID_ARGUMENT - if the hue is not between 0 and 360 or
* the saturation or brightness is not between 0 and 1 or if the alpha
* is not between 0 and 255</li>
* </ul>
*
*/
public RGBA( float hue, float saturation, float brightness, float alpha ) {
if( alpha > 255 || alpha < 0 ) {
SWT.error( SWT.ERROR_INVALID_ARGUMENT );
}
rgb = new RGB( hue, saturation, brightness );
this.alpha = ( int )( alpha + 0.5 );
}
/**
* Returns the hue, saturation, and brightness of the color.
*
* @return color space values in float format:<ul>
* <li>hue (from 0 to 360)</li>
* <li>saturation (from 0 to 1)</li>
* <li>brightness (from 0 to 1)</li>
* <li>alpha (from 0 to 255)</li>
* </ul>
* @see #RGBA(float, float, float, float)
*/
public float[] getHSBA() {
float[] hsb = rgb.getHSB();
return new float[] {
hsb[ 0 ],
hsb[ 1 ],
hsb[ 2 ],
alpha
};
}
/**
* Compares the argument to the receiver, and returns true
* if they represent the <em>same</em> object using a class
* specific comparison.
*
* @param object the object to compare with this object
* @return <code>true</code> if the object is the same as this object and <code>false</code> otherwise
*
* @see #hashCode()
*/
@Override
public boolean equals( Object object ) {
if( object == this ) {
return true;
}
if( !( object instanceof RGBA ) ) {
return false;
}
RGBA rgba = ( RGBA )object;
return ( rgba.rgb.red == this.rgb.red )
&& ( rgba.rgb.green == this.rgb.green )
&& ( rgba.rgb.blue == this.rgb.blue )
&& ( rgba.alpha == this.alpha );
}
/**
* Returns an integer hash code for the receiver. Any two
* objects that return <code>true</code> when passed to
* <code>equals</code> must return the same value for this
* method.
*
* @return the receiver's hash
*
* @see #equals(Object)
*/
@Override
public int hashCode() {
return ( alpha << 32 ) | ( rgb.blue << 16 ) | ( rgb.green << 8 ) | rgb.red;
}
/**
* Returns a string containing a concise, human-readable
* description of the receiver.
*
* @return a string representation of the <code>RGBA</code>
*/
@Override
public String toString() {
return "RGBA {" + rgb.red + ", " + rgb.green + ", " + rgb.blue + ", " + alpha + "}";
}
}