Attachment 11217 Details for Bug 55750 – Patch to add RGBContrastFactory

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[patch] Patch to add RGBContrastFactory

contrast-factory.diff (text/plain), 5.87 KB, created by Billy Biggs

on 2004-05-27 12:48:24 EDT

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Creator: Billy Biggs

Created: 2004-05-27 12:48:24 EDT

Size: 5.87 KB

patch

obsolete

>Index: Eclipse UI/org/eclipse/ui/internal/themes/RGBContrastFactory.java
>===================================================================
>RCS file: Eclipse UI/org/eclipse/ui/internal/themes/RGBContrastFactory.java
>diff -N Eclipse UI/org/eclipse/ui/internal/themes/RGBContrastFactory.java
>--- /dev/null	1 Jan 1970 00:00:00 -0000
>+++ Eclipse UI/org/eclipse/ui/internal/themes/RGBContrastFactory.java	1 Jan 1970 00:00:00 -0000
>@@ -0,0 +1,150 @@
>+/*******************************************************************************
>+ * Copyright (c) 2004 IBM Corporation and others.
>+ * All rights reserved. This program and the accompanying materials 
>+ * are made available under the terms of the Common Public License v1.0
>+ * which accompanies this distribution, and is available at
>+ * http://www.eclipse.org/legal/cpl-v10.html
>+ * 
>+ * Contributors:
>+ * IBM Corporation - initial API and implementation
>+ *******************************************************************************/
>+package org.eclipse.ui.internal.themes;
>+
>+import java.util.Hashtable;
>+
>+import org.eclipse.core.runtime.CoreException;
>+import org.eclipse.core.runtime.IConfigurationElement;
>+import org.eclipse.core.runtime.IExecutableExtension;
>+import org.eclipse.swt.graphics.RGB;
>+import org.eclipse.ui.themes.IColorFactory;
>+
>+
>+/**
>+ * A <code>IColorFactory</code> that may be used to select a colour with
>+ * a higher contrast. The colors to blend are specified as per method
>+ * number two in {@link org.eclipse.core.runtime.IExecutableExtension}.
>+ * 
>+ * Example usage:
>+ * 
>+ * <code>
>+ * &lt;colorDefinition
>+ * label="Red/Blue Contrast"
>+ * id="example.redblueblend"&gt;
>+ * &lt;colorFactory 
>+ * 				plugin="org.eclipse.ui" 
>+ * 				class="org.eclipse.ui.internal.themes.RGBContrastFactory"&gt;
>+ * 	&lt;parameter name="foreground" value="0,0,0" /&gt;
>+ * 		&lt;parameter name="background1" value="COLOR_RED" /&gt;
>+ * &lt;parameter name="background2" value="COLOR_BLUE" /&gt;
>+ * &lt;/colorFactory&gt;
>+ * &lt;/colorDefinition&gt;
>+ * </code>
>+ * 
>+ * 
>+ * 
>+ * This will select whichever of Red or Blue has a higher contrst with black.
>+ * The color values may be specified as RGB triples or as SWT constants.
>+ * 
>+ * 
>+ * @see org.eclipse.swt.SWT
>+ * @since 3.0
>+ */
>+public class RGBContrastFactory implements IColorFactory, IExecutableExtension {
>+ private String fg, bg1, bg2;
>+
>+ /**
>+ * Returns the intensity of an RGB component using the
>+ * sRGB gamma function.
>+ * 
>+ * @param val Value to convert.
>+ * @return Light intensity of the component.
>+ */
>+ double voltage_to_intensity_srgb( double val ) { 
>+ /* Handle invalid values before doing a gamma transform. */
>+ if( val < 0.0 ) return 0.0;
>+ if( val > 1.0 ) return 1.0;
>+
>+ if( val <= 0.04045 ) {
>+ return val / 12.92;
>+ }
>+ return Math.pow( ( val + 0.055 ) / 1.055, 2.4 );
>+ }
>+
>+ /**
>+ * Returns a measure of the lightness in the perceptual colourspace
>+ * IPT.
>+ * 
>+ * @param color The colour in sRGB
>+ * @return Lightness in IPT space.
>+ */
>+ double lightness( RGB color ) {
>+ double r = voltage_to_intensity_srgb( color.red / 255.0 );
>+ double g = voltage_to_intensity_srgb( color.green / 255.0 );
>+ double b = voltage_to_intensity_srgb( color.blue / 255.0 );
>+ double l = (0.3139 * r) + (0.6395 * g) + (0.0466 * b);
>+ double m = (0.1516 * r) + (0.7482 * g) + (0.1000 * b);
>+ double s = (0.0177 * r) + (0.1095 * g) + (0.8729 * b);
>+ double lp, mp, sp;
>+ 
>+ if( l < 0.0 ) lp = -Math.pow( -l, 0.43 ); else lp = Math.pow( l, 0.43 );
>+ if( m < 0.0 ) mp = -Math.pow( -m, 0.43 ); else mp = Math.pow( m, 0.43 );
>+ if( s < 0.0 ) sp = -Math.pow( -s, 0.43 ); else sp = Math.pow( s, 0.43 );
>+
>+ return (0.4000 * lp) + (0.4000 *mp) + (0.2000 * sp);
>+ }
>+ 
>+ public RGB createColor() {
>+ /**
>+ * Determine which pair has a higher contrast by selecting
>+ * the colour with the furthest distance in lightness.
>+ */
>+ RGB cfg, cbg1, cbg2;
>+
>+ if( fg != null ) {
>+ cfg = ColorUtils.getColorValue( fg );
>+ } else {
>+ cfg = new RGB(255,255,255);
>+ }
>+ if( bg1 != null ) {
>+ cbg1 = ColorUtils.getColorValue( bg1 );
>+ } else {
>+ cbg1 = new RGB(0, 0, 0);
>+ }
>+ if( bg2 != null ) {
>+ cbg2 = ColorUtils.getColorValue( bg2 );
>+ } else {
>+ cbg2 = new RGB(0, 0, 0);
>+ }
>+
>+ double lfg = lightness( cfg );
>+ double lbg1 = lightness( cbg1 );
>+ double lbg2 = lightness( cbg2 );
>+
>+ if( Math.abs(lbg1 - lfg) > Math.abs(lbg2 - lfg) ) {
>+ return cbg1;
>+ } else {
>+ return cbg2;
>+ }
>+ }
>+
>+ /**
>+ * This executable extension requires parameters to be explicitly declared 
>+ * via the second method described in the <code>IExecutableExtension</code> 
>+ * documentation. This class expects that there will be three parameters, 
>+ * <code>foreground</code>, <code>background1</code> and
>+ * <code>background2</code>, that describe the two colors to be blended.
>+ * These values may either be RGB triples or SWT constants.
>+ * 
>+ * @see org.eclipse.core.runtime.IExecutableExtension#setInitializationData(org.eclipse.core.runtime.IConfigurationElement, java.lang.String, java.lang.Object)
>+ */
>+ public void setInitializationData(IConfigurationElement config,
>+ String propertyName, Object data) throws CoreException {
>+ if (data instanceof Hashtable) {
>+ Hashtable table = (Hashtable)data;
>+ fg = (String) table.get("foreground"); //$NON-NLS-1$
>+ bg1 = (String) table.get("background1"); //$NON-NLS-1$
>+ bg2 = (String) table.get("background2"); //$NON-NLS-1$
>+ }
>+
>+ }
>+}

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Attachments on bug 55750: 11217 | 11218