SquirrelJME/SquirrelJME

// -*- Mode: Java; indent-tabs-mode: t; tab-width: 4 -*-
// ---------------------------------------------------------------------------
// SquirrelJME
//     Copyright (C) Stephanie Gawroriski <xer@multiphasicapps.net>
// ---------------------------------------------------------------------------
// SquirrelJME is under the Mozilla Public License Version 2.0.
// See license.mkd for licensing and copyright information.
// ---------------------------------------------------------------------------

package net.multiphasicapps.lcduidemo;

import java.io.IOException;
import java.io.InputStream;
import javax.microedition.lcdui.Canvas;
import javax.microedition.lcdui.Display;
import javax.microedition.lcdui.Graphics;
import javax.microedition.lcdui.Image;
import javax.microedition.lcdui.game.Sprite;
import javax.microedition.midlet.MIDlet;
import javax.microedition.midlet.MIDletStateChangeException;

/**
 * This is the base for image demos.
 *
 * @since 2019/04/15
 */
public abstract class AbstractImageDemo
    extends MIDlet
{
    /** No mirrors. */
    static final int[] _NO_MIRROR =
        new int[]{Sprite.TRANS_NONE, Sprite.TRANS_ROT90,
            Sprite.TRANS_ROT180, Sprite.TRANS_ROT270};
            
    /** Mirrors. */
    static final int[] _MIRROR =
        new int[]{Sprite.TRANS_MIRROR, Sprite.TRANS_MIRROR_ROT90,
            Sprite.TRANS_MIRROR_ROT180, Sprite.TRANS_MIRROR_ROT270};
    
    /** The image to use. */
    protected final Image image;
    
    /**
     * Initializes the image demo.
     *
     * @param __in Input stream.
     * @throws NullPointerException On null arguments.
     * @since 2019/04/15
     */
    public AbstractImageDemo(InputStream __in)
        throws NullPointerException
    {
        // Load image data
        try
        {
            this.image = Image.createImage(__in);
        }
        
        // Fail
        catch (IOException e)
        {
            throw new RuntimeException(e);
        }
    }
    
    /**
     * {@inheritDoc}
     * @since 2019/04/15
     */
    @Override
    protected void destroyApp(boolean __uc)
        throws MIDletStateChangeException
    {
    }
    
    /**
     * {@inheritDoc}
     * @since 2019/04/15
     */
    @Override
    protected void startApp()
        throws MIDletStateChangeException
    {
        // Setup canvas
        DemoCanvas cv = new DemoCanvas(this.image);
        cv.setTitle("Image Demo");
        
        // Exit command
        cv.addCommand(Exit.command);
        cv.setCommandListener(new Exit());
        
        // We do not draw every pixel
        cv.setPaintMode(false);
        
        // Set display to the canvas
        Display.getDisplay(this).setCurrent(cv);
    }
    
    /**
     * The demo canvas which does the drawing.
     *
     * @since 2019/04/15
     */
    public static final class DemoCanvas
        extends Canvas
    {
        /** The image to draw. */
        protected final Image image;
        
        /**
         * Initializes the demo canvas.
         *
         * @param __i The image to use.
         * @throws NullPointerException On null arguments.
         * @since 2019/04/15
         */
        public DemoCanvas(Image __i)
            throws NullPointerException
        {
            if (__i == null)
                throw new NullPointerException("NARG");
            
            this.image = __i;
            
            // We do not draw over every pixel
            this.setPaintMode(false);
        }
        
        /**
         * {@inheritDoc}
         * @since 2018/11/22
         */
        @Override
        public void paint(Graphics __g)
        {
            // Get image
            Image image = this.image;
            int w = image.getWidth(),
                h = image.getHeight();
            
            // Base Y position
            int basey = 0;
            
            // Draw portions of the image
            for (int i = 0; i < 4; i++)
            {
                // Determine x and y offset
                int xoff = (((i & 0b01) == 0) ? 0 : w >>> 1),
                    yoff = (((i & 0b10) == 0) ? 0 : h >>> 1);
                
                // Source X and Y dimensions
                int sx = xoff,
                    sy = yoff,
                    sw = w - xoff,
                    sh = h - yoff;
                
                // Non-mirrored rotations
                for (int j = 0; j < AbstractImageDemo._NO_MIRROR.length; j++)
                    __g.drawRegion(image, sx, sy, sw, sh,
                        AbstractImageDemo._NO_MIRROR[j],
                        (w * j), basey, 0);
                basey += h;
                    
                // Mirrored rotations
                for (int j = 0; j < AbstractImageDemo._MIRROR.length; j++)
                    __g.drawRegion(image, sx, sy, sw, sh,
                        AbstractImageDemo._MIRROR[j],
                        (w * j), basey, 0);
                basey += h;
            }
            
            // Plain image drawing
            __g.drawImage(image, 0, basey,
                Graphics.TOP | Graphics.LEFT);
        }
    }
}