PaintUtils.java

/*
Copyright 2008-2010 Gephi
Authors : Mathieu Bastian <mathieu.bastian@gephi.org>
Website : http://www.gephi.org

This file is part of Gephi.

Gephi is free software: you can redistribute it and/or modify
it under the terms of the GNU Affero General Public License as
published by the Free Software Foundation, either version 3 of the
License, or (at your option) any later version.

Gephi is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU Affero General Public License for more details.

You should have received a copy of the GNU Affero General Public License
along with Gephi.  If not, see <http://www.gnu.org/licenses/>.
*/
package org.gephi.ui.components.gradientslider;

import java.awt.BasicStroke;
import java.awt.Color;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.Rectangle;
import java.awt.Shape;

import javax.swing.SwingConstants;
import javax.swing.UIManager;


// Author Jeremy Wood
public class PaintUtils {

    /** Four shades of white, each with increasing opacity. */
    public final static Color[] whites = new Color[]{
        new Color(255, 255, 255, 50),
        new Color(255, 255, 255, 100),
        new Color(255, 255, 255, 150)
    };
    /** Four shades of black, each with increasing opacity. */
    public final static Color[] blacks = new Color[]{
        new Color(0, 0, 0, 50),
        new Color(0, 0, 0, 100),
        new Color(0, 0, 0, 150)
    };

    /** @return the color used to indicate when a component has
     * focus.  By default this uses the color (64,113,167), but you can
     * override this by calling:
     * <BR><code>UIManager.put("focusRing",customColor);</code>
     */
    public static Color getFocusRingColor() {
        Object obj = UIManager.getColor("focusRing");
        if (obj instanceof Color) {
            return (Color) obj;
        }
        return new Color(64, 113, 167);
    }

    /** Paints 3 different strokes around a shape to indicate focus.
     * The widest stroke is the most transparent, so this achieves a nice
     * "glow" effect.
     * <P>The catch is that you have to render this underneath the shape,
     * and the shape should be filled completely.
     *
     * @param g the graphics to paint to
     * @param shape the shape to outline
     * @param biggestStroke the widest stroke to use.
     */
    public static void paintFocus(Graphics2D g, Shape shape, int biggestStroke) {
        Color focusColor = getFocusRingColor();
        Color[] focusArray = new Color[]{
            new Color(focusColor.getRed(), focusColor.getGreen(), focusColor.getBlue(), 255),
            new Color(focusColor.getRed(), focusColor.getGreen(), focusColor.getBlue(), 170),
            new Color(focusColor.getRed(), focusColor.getGreen(), focusColor.getBlue(), 110)
        };
        g.setStroke(new BasicStroke(biggestStroke));
        g.setColor(focusArray[2]);
        g.draw(shape);
        g.setStroke(new BasicStroke(biggestStroke - 1));
        g.setColor(focusArray[1]);
        g.draw(shape);
        g.setStroke(new BasicStroke(biggestStroke - 2));
        g.setColor(focusArray[0]);
        g.draw(shape);
        g.setStroke(new BasicStroke(1));
    }

    /** Uses translucent shades of white and black to draw highlights
     * and shadows around a rectangle, and then frames the rectangle
     * with a shade of gray (120).
     * <P>This should be called to add a finishing touch on top of
     * existing graphics.
     * @param g the graphics to paint to.
     * @param r the rectangle to paint.
     */
    public static void drawBevel(Graphics g, Rectangle r) {
        drawColors(blacks, g, r.x, r.y + r.height, r.x + r.width, r.y + r.height, SwingConstants.SOUTH);
        drawColors(blacks, g, r.x + r.width, r.y, r.x + r.width, r.y + r.height, SwingConstants.EAST);

        drawColors(whites, g, r.x, r.y, r.x + r.width, r.y, SwingConstants.NORTH);
        drawColors(whites, g, r.x, r.y, r.x, r.y + r.height, SwingConstants.WEST);

        g.setColor(new Color(120, 120, 120));
        g.drawRect(r.x, r.y, r.width, r.height);
    }

    private static void drawColors(Color[] colors, Graphics g, int x1, int y1, int x2, int y2, int direction) {
        for (int a = 0; a < colors.length; a++) {
            g.setColor(colors[colors.length - a - 1]);
            if (direction == SwingConstants.SOUTH) {
                g.drawLine(x1, y1 - a, x2, y2 - a);
            } else if (direction == SwingConstants.NORTH) {
                g.drawLine(x1, y1 + a, x2, y2 + a);
            } else if (direction == SwingConstants.EAST) {
                g.drawLine(x1 - a, y1, x2 - a, y2);
            } else if (direction == SwingConstants.WEST) {
                g.drawLine(x1 + a, y1, x2 + a, y2);
            }
        }
    }
}