Palette.java

/**
 * Palette.java
 *
 * Copyright (c) 2013-2016, F(X)yz
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *     * Redistributions of source code must retain the above copyright
 * notice, this list of conditions and the following disclaimer.
 *     * Redistributions in binary form must reproduce the above copyright
 * notice, this list of conditions and the following disclaimer in the
 * documentation and/or other materials provided with the distribution.
 *     * Neither the name of F(X)yz, any associated website, nor the
 * names of its contributors may be used to endorse or promote products
 * derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED. IN NO EVENT SHALL F(X)yz BE LIABLE FOR ANY
 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */ 

package org.fxyz3d.scene.paint;

import java.io.File;
import java.io.IOException;
import java.util.Arrays;
import java.util.List;
import java.util.concurrent.atomic.AtomicInteger;
import java.util.stream.DoubleStream;
import java.util.stream.IntStream;
import javafx.embed.swing.SwingFXUtils;
import javafx.scene.image.Image;
import javafx.scene.image.PixelWriter;
import javafx.scene.image.WritableImage;
import javafx.scene.paint.Color;
import javax.imageio.ImageIO;

/**
 *
 * @author jpereda
 */
public class Palette {
    
    public enum ColorPalette {
        HSB,GREEN
    }
    
    private final List<Color> GREEN_COLORS = Arrays.asList(Color.rgb(0,0,0,1),Color.rgb(30,49,29,1),
            Color.rgb(35,80,33,1),Color.rgb(56,122,54,1),Color.rgb(45,187,40,1),Color.rgb(8,231,0,1));
    
    private final int numColors;
    private final ColorPalette colorPalette;
    private int width;
    private int height;
    private Image imgPalette;
    
    private final static ColorPalette DEFAULT_COLOR_PALETTE = ColorPalette.HSB;
    private final static int DEFAULT_NUMCOLORS = 10000; // 100x100 palette image
    
    public Palette(){
        this(DEFAULT_NUMCOLORS, DEFAULT_COLOR_PALETTE);
    }
    
    public Palette(int numColors){
        this(numColors, DEFAULT_COLOR_PALETTE);
    }
    
    public Palette(int numColors, ColorPalette colorPalette){
        this.numColors=numColors;
        this.colorPalette = colorPalette;
    }
    
    public Image createPalette(boolean save){
        if(numColors<1){
            return null;
        }
        // try to create a square image
        width=(int)Math.sqrt(numColors);
        height=numColors/width;
        
        imgPalette = new WritableImage(width, height);
        PixelWriter   pw  = ((WritableImage)imgPalette).getPixelWriter();
        AtomicInteger count = new AtomicInteger();
        IntStream.range(0, height).boxed()
                .forEach(y->IntStream.range(0, width).boxed()
                        .forEach(x->pw.setColor(x, y, getColor(count.getAndIncrement()))));
        if(save){
            saveImage();
        }
        return imgPalette;
    }
    
    public DoubleStream getTextureLocation(int iPoint){
        if(width==0 || height==0){
            return DoubleStream.of(0f,0f);
        }
        int y = iPoint/width; 
        int x = iPoint-width*y;
        // add 0.5 to interpolate colors from the middle of the pixel
        return DoubleStream.of((((float)x+0.5f)/((float)width)),(((float)y+0.5f)/((float)height)));
    }
    
    private void saveImage(){
        try {
            // save
            ImageIO.write(SwingFXUtils.fromFXImage(imgPalette, null), "png", new File("palette_"+numColors+".png"));
        } catch (IOException ex) { 
            System.out.println("Error saving image");
        }
    }
    
    /*
        int iColor [0-numColors]
    */
    private Color getColor(int iColor){
        double fact=(double) (iColor) / (double) numColors;
        switch(colorPalette){
            case HSB:
//                if (iColor == 0) {
//                    return Color.TRANSPARENT;
//                }
                // There are 6*255=1530 distinct pure colors, 255 colors every 60º, with 100% saturation and value
                return Color.hsb(360d*fact, 1d, 1d);
            case GREEN:
                return GREEN_COLORS.get((int)(fact*GREEN_COLORS.size()));
        } 
        return Color.rgb((iColor >> 16) & 0xFF, (iColor >> 8) & 0xFF, iColor & 0xFF);
    }
    
    public int getNumColors() {
        return numColors;
    }

    public int getWidth() {
        return width;
    }

    public int getHeight() {
        return height;
    }

    public Image getPaletteImage() {
        return imgPalette;
    }
    
    public ColorPalette getColorPalette(){
        return colorPalette;
    }
    
}