8.9.6. Picture Lab A8: Creating a Collage

Picture Lab A8: Run to see createCollage() working.

import java.awt.*;
import java.awt.font.*;
import java.awt.geom.*;
import java.awt.image.BufferedImage;
import java.text.*;
import java.util.*;

/**
 * A class that represents a picture. This class inherits from SimplePicture and
 * allows the student to add functionality to the Picture class.
 *
 * @author Barbara Ericson ericson@cc.gatech.edu
 */
public class Picture extends SimplePicture
{
    ///////////////////// constructors //////////////////////////////////

/** Constructor that takes no arguments */
    public Picture()
    {
        /* not needed but use it to show students the implicit call to super()
         * child constructors always call a parent constructor
         */
        super();
    }

/**
     * Constructor that takes a file name and creates the picture
     *
     * @param fileName the name of the file to create the picture from
     */
    public Picture(String fileName)
    {
        // let the parent class handle this fileName
        super(fileName);
    }

/**
     * Constructor that takes the height and width
     *
     * @param height the height of the desired picture
     * @param width the width of the desired picture
     */
    public Picture(int width, int height)
    {
        // let the parent class handle this width and height
        super(width, height);
    }

/**
     * Constructor that takes a picture and creates a copy of that picture
     *
     * @param copyPicture the picture to copy
     */
    public Picture(Picture copyPicture)
    {
        // let the parent class do the copy
        super(copyPicture);
    }

/**
     * Constructor that takes a buffered image
     *
     * @param image the buffered image to use
     */
    public Picture(BufferedImage image)
    {
        super(image);
    }

////////////////////// methods ///////////////////////////////////////

/**
     * Method to return a string with information about this picture.
     *
     * @return a string with information about the picture such as fileName, height
     *     and width.
     */
    public String toString()
    {
        String output =
                "Picture, filename "
                        + getFileName()
                        + " height "
                        + getHeight()
                        + " width "
                        + getWidth();
        return output;
    }

/** zeroBlue() method sets the blue values at all pixels to zero */
    public void zeroBlue()
    {
        Pixel[][] pixels = this.getPixels2D();

for (Pixel[] rowArray : pixels)
        {
            for (Pixel p : rowArray)
            {
                p.setBlue(0);
            }
        }
    }

/* mirrorVertical() */
    public void mirrorVertical()
    {
        Pixel[][] pixels = this.getPixels2D();
        Pixel leftPixel = null;
        Pixel rightPixel = null;
        int width = pixels[0].length;
        for (int row = 0; row < pixels.length; row++)
        {
            for (int col = 0; col < width / 2; col++)
            {
                leftPixel = pixels[row][col];
                rightPixel = pixels[row][width - 1 - col];
                rightPixel.setColor(leftPixel.getColor());
            }
        }
    }

/**
     * copy from the passed fromPic to the specified startRow and startCol in the
     * current picture
     *
     * @param fromPic the picture to copy from
     * @param startRow the start row to copy to
     * @param startCol the start col to copy to
     */
    public void copy(Picture fromPic, int startRow, int startCol)
    {
        Pixel fromPixel = null;
        Pixel toPixel = null;
        Pixel[][] toPixels = this.getPixels2D();
        Pixel[][] fromPixels = fromPic.getPixels2D();
        for (int fromRow = 0, toRow = startRow;
                fromRow < fromPixels.length && toRow < toPixels.length;
                fromRow++, toRow++)
                {
            for (int fromCol = 0, toCol = startCol;
                    fromCol < fromPixels[0].length && toCol < toPixels[0].length;
                    fromCol++, toCol++)
                    {
                fromPixel = fromPixels[fromRow][fromCol];
                toPixel = toPixels[toRow][toCol];
                toPixel.setColor(fromPixel.getColor());
            }
        }
    }

public void createCollage()
    {
        // You can also try butterfly.jpg and snowflake.jpg
        Picture flower1 = new Picture("flower1.jpg");
        Picture flower2 = new Picture("flower2.jpg");
        this.copy(flower1, 0, 0);
        this.copy(flower2, 100, 0);
        this.copy(flower1, 200, 0);
        Picture flowerNoBlue = new Picture(flower2);
        flowerNoBlue.zeroBlue();
        this.copy(flowerNoBlue, 300, 0);
        this.copy(flower1, 400, 0);
        this.copy(flower2, 500, 0);
        this.mirrorVertical();
        this.show();
    }

/* Main method for testing
     */
    public static void main(String[] args)
    {
        Picture p = new Picture(500, 500);
        p.createCollage();
    }
}

====
import static org.junit.Assert.*;

import org.junit.*;

import java.io.*;

public class RunestoneTests extends CodeTestHelper
{
    @Test
    public void test1()
    {
        String target = "public void createCollage()";
        boolean passed = checkCodeContains("createCollage() method", target);
        assertTrue(passed);
    }
}

Picture Lab A8: Create a second copy method called copyPartial that adds parameters to allow you to copy just part of the fromPic. You will need to add parameters that specify the start row, end row, start column, and end column to copy from. Use it in your collage.