Closes #8 and closes #9

README.md

@@ -11,6 +11,6 @@ Mit der Zechenmaschine können Schüler:innen ihre Programme von Anfang an mit
 Visualisierungen und Interaktionen ausstatten, ohne sich mit der GUI Programmierung 
 mit Java Swing auseinandersetzen zu müssen.
 
-Die Bibliothek wurde sich stark on [Processing](https://processing.org),
+Die Bibliothek wurde stark on [Processing](https://processing.org),
 [Engine Alpha](https://engine-alpha.org) und [TigerJython](https://www.tigerjython.ch/de)
 inspiriert.

src/schule/ngb/zm/ColorLayer.java

@@ -9,6 +9,12 @@ public class ColorLayer extends Layer {
 		clear();
 	}
 
+	public ColorLayer( int width, int height, Color color ) {
+		super(width, height);
+		this.background = color;
+		clear();
+	}
+
 	@Override
 	public void setSize( int width, int height ) {
 		super.setSize(width, height);

src/schule/ngb/zm/Constants.java

@@ -8,8 +8,8 @@ public class Constants {
 	public static final String APP_NAME = "Zeichenmaschine";
 
 	public static final int APP_VERSION_MAJ = 0;
-	public static final int APP_VERSION_MIN = 1;
-	public static final int APP_VERSION_REV = 5;
+	public static final int APP_VERSION_MIN = 0;
+	public static final int APP_VERSION_REV = 8;
 
 	public static final String APP_VERSION = APP_VERSION_MAJ + "." + APP_VERSION_MIN + "." + APP_VERSION_REV;
 

src/schule/ngb/zm/ImageLayer.java

@@ -16,11 +16,6 @@ public class ImageLayer extends Layer {
 
 	protected boolean redraw = true;
 
-	public ImageLayer() {
-
-	}
-
-
 	public ImageLayer( String source ) {
 		image = ImageLoader.loadImage(source);
 	}

src/schule/ngb/zm/Zeichenleinwand.java

@@ -30,9 +30,9 @@ public class Zeichenleinwand extends Canvas {
 		// Liste der Ebenen initialisieren und die Standardebenen einfügen
 		layers = new LinkedList<>();
 		synchronized( layers ) {
-			layers.add(new ColorLayer(Constants.STD_BACKGROUND));
-			layers.add(new DrawingLayer());
-			layers.add(new ShapesLayer());
+			layers.add(new ColorLayer(width, height, Constants.STD_BACKGROUND));
+			layers.add(new DrawingLayer(width, height));
+			layers.add(new ShapesLayer(width, height));
 		}
 	}
 
@@ -160,6 +160,16 @@ public class Zeichenleinwand extends Canvas {
 		render();
 	}
 
+	public void draw( Graphics graphics ) {
+		Graphics2D g2d = (Graphics2D) graphics.create();
+		synchronized( layers ) {
+			for( Layer layer : layers ) {
+				layer.draw(g2d);
+			}
+		}
+		g2d.dispose();
+	}
+
 	public void render() {
 		if( getBufferStrategy() == null ) {
 			allocateBuffer();
@@ -192,16 +202,6 @@ public class Zeichenleinwand extends Canvas {
 					// Repeat the rendering if the drawing buffer was lost
 				} while( strategy.contentsLost() );
 			}
-
-			/*
-			Graphics2D g2d = (Graphics2D) g.create();
-
-			for( Layer layer : layers ) {
-				layer.draw(g2d);
-			}
-
-			g2d.dispose();
-			*/
 		}
 	}
 }

src/schule/ngb/zm/Zeichenmaschine.java

@@ -1,15 +1,21 @@
 package schule.ngb.zm;
 
 import schule.ngb.zm.shapes.ShapesLayer;
+import schule.ngb.zm.util.ImageLoader;
 
 import javax.swing.*;
 import javax.swing.event.MouseInputListener;
 import java.awt.*;
+import java.awt.Color;
 import java.awt.event.*;
+import java.awt.image.BufferedImage;
+import java.awt.image.RescaleOp;
+import java.io.File;
+import java.io.IOException;
 
 /**
  * Hauptklasse der Zeichenmaschine.
- *
+ * <p>
  * Projekte der Zeichenmaschine sollten als Unterklasse implementiert werden.
  * Die Klasse übernimmt die Initialisierung eines Programmfensters und der
  * nötigen Komponenten.
@@ -25,6 +31,7 @@ public class Zeichenmaschine extends Constants implements MouseInputListener, Ke
 	/*
 	 * Attributes to be accessed by subclasses.
 	 */
+
 	protected Zeichenleinwand canvas;
 
 	protected ColorLayer background;
@@ -41,18 +48,24 @@ public class Zeichenmaschine extends Constants implements MouseInputListener, Ke
 
 	protected double mouseX = 0.0, mouseY = 0.0, pmouseX = 0.0, pmouseY = 0.0;
 
-	protected int width = STD_WIDTH, height = STD_HEIGHT;
+	protected int width, height;
+
+	protected int screenWidth, screenHeight;
+
+	/*
+	 * Interne Attribute zur Steuerung der Zeichenmaschine.
+	 */
 
 	private Object mouseLock = new Object();
 
 	private Object keyboardLock = new Object();
 
-	/*
-	 * Interne Attribute zur Steuerung der Zeichenamschine.
-	 */
-	//
 	private JFrame frame;
 
+	private GraphicsEnvironment environment;
+
+	private GraphicsDevice displayDevice;
+
 	private boolean running = false, isDrawing = false, isUpdating = false;
 
 	private int framesPerSecond;
@@ -61,6 +74,7 @@ public class Zeichenmaschine extends Constants implements MouseInputListener, Ke
 
 	private boolean quitAfterTeardown = false, initialized = false;
 
+
 	public Zeichenmaschine() {
 		this(APP_NAME + " " + APP_VERSION);
 	}
@@ -73,20 +87,37 @@ public class Zeichenmaschine extends Constants implements MouseInputListener, Ke
 		try {
 			UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
 		} catch( Exception e ) {
-			System.err.println("Error setting the look and feel.");
+			System.err.println("Error setting the look and feel: " + e.getMessage());
 		}
 
-		GraphicsEnvironment environment =
-			GraphicsEnvironment.getLocalGraphicsEnvironment();
-		GraphicsDevice displayDevice = environment.getDefaultScreenDevice();
+
+		// Looking for the screen currently holding the mouse pointer
+		// that will be used as the screen device for this Zeichenmaschine
+		java.awt.Point mouseLoc = MouseInfo.getPointerInfo().getLocation();
+		environment = GraphicsEnvironment.getLocalGraphicsEnvironment();
+		GraphicsDevice[] devices = environment.getScreenDevices();
+		for( GraphicsDevice gd: devices ) {
+			if( gd.getDefaultConfiguration().getBounds().contains(mouseLoc) ) {
+				displayDevice = gd;
+				break;
+			}
+		}
+		if( displayDevice == null ) {
+			displayDevice = environment.getDefaultScreenDevice();
+		}
+
+
+		this.width = width;
+		this.height = height;
+		java.awt.Rectangle displayBounds = displayDevice.getDefaultConfiguration().getBounds();
+		this.screenWidth = (int)displayBounds.getWidth();
+		this.screenHeight = (int)displayBounds.getHeight();
+
 
 		frame = new JFrame(displayDevice.getDefaultConfiguration());
 		frame.setTitle(title);
 		frame.setDefaultCloseOperation(WindowConstants.DO_NOTHING_ON_CLOSE);
 
-		this.width = width;
-		this.height = height;
-
 		canvas = new Zeichenleinwand(width, height);
 		frame.add(canvas);
 
@@ -96,6 +127,7 @@ public class Zeichenmaschine extends Constants implements MouseInputListener, Ke
 		drawing = getDrawingLayer();
 		shapes = getShapesLayer();
 
+		// TODO: When to call settings?
 		settings();
 
 		canvas.addMouseListener(this);
@@ -114,9 +146,7 @@ public class Zeichenmaschine extends Constants implements MouseInputListener, Ke
 
 		frame.pack();
 		frame.setResizable(false);
-		// TODO: Center on current display (not main display by default)
-		// TODO: Position at current BlueJ windows if IN_BLUEJ
-		frame.setLocationRelativeTo(null);
+		centerFrame();
 		frame.setVisible(true);
 
 		canvas.allocateBuffer();
@@ -148,6 +178,19 @@ public class Zeichenmaschine extends Constants implements MouseInputListener, Ke
 		}
 	}
 
+	public final void centerFrame() {
+		// TODO: Center on current display (not main display by default)
+		// TODO: Position at current BlueJ windows if IN_BLUEJ
+		//frame.setLocationRelativeTo(null);
+		//frame.setLocationRelativeTo(displayDevice.getFullScreenWindow());
+
+		java.awt.Rectangle bounds = displayDevice.getDefaultConfiguration().getBounds();
+		frame.setLocation(
+			(int)(bounds.x + (screenWidth-frame.getWidth())/2.0),
+			(int)(bounds.y + (screenHeight-frame.getHeight())/2.0)
+		);
+	}
+
 	public final void redraw() {
 		canvas.render();
 		//canvas.invalidate();
@@ -242,6 +285,64 @@ public class Zeichenmaschine extends Constants implements MouseInputListener, Ke
 		framesPerSecond = pFramesPerSecond;
 	}
 
+	public void saveImage() {
+		JFileChooser jfc = new JFileChooser();
+		jfc.setFileSelectionMode(JFileChooser.FILES_AND_DIRECTORIES);
+		jfc.setMultiSelectionEnabled(false);
+
+		int status = jfc.showSaveDialog(frame);
+		if( status == JFileChooser.APPROVE_OPTION ) {
+			File outfile = jfc.getSelectedFile();
+			if( outfile.isDirectory() ) {
+				outfile = new File(outfile.getAbsolutePath() + File.separator + "zeichenmaschine.png");
+			}
+			saveImage(outfile.getAbsolutePath());
+		}
+	}
+
+	public void saveImage( String filepath ) {
+		BufferedImage img = new BufferedImage(canvas.getWidth(),canvas.getHeight(), BufferedImage.TYPE_INT_RGB);
+
+		Graphics2D g = img.createGraphics();
+		g.setColor(STD_BACKGROUND.getColor());
+		g.fillRect(0, 0, img.getWidth(), img.getHeight());
+		canvas.draw(g);
+		g.dispose();
+
+		try {
+			ImageLoader.saveImage(img, new File(filepath), true);
+		} catch ( IOException ex ) {
+			ex.printStackTrace();
+		}
+	}
+
+	public ImageLayer snapshot() {
+		BufferedImage img = new BufferedImage(canvas.getWidth(),canvas.getHeight(), BufferedImage.TYPE_INT_RGB);
+
+		Graphics2D g = img.createGraphics();
+		g.setColor(STD_BACKGROUND.getColor());
+		g.fillRect(0, 0, img.getWidth(), img.getHeight());
+		canvas.draw(g);
+		g.dispose();
+
+		/*
+		float factor = 0.8f;
+		float base = 255f * (1f - factor);
+		RescaleOp op = new RescaleOp(factor, base, null);
+		BufferedImage filteredImage
+			= new BufferedImage(img.getWidth(), img.getHeight(), img.getType());
+		op.filter(img, filteredImage);
+		*/
+
+		ImageLayer imgLayer = new ImageLayer(img);
+		if( canvas.getLayer(0) instanceof ColorLayer ) {
+			canvas.addLayer(1, imgLayer);
+		} else {
+			canvas.addLayer(0, imgLayer);
+		}
+		return imgLayer;
+	}
+
 	/*
 	 * Methoden, die von Unterklassen überschrieben werden können / sollen.
 	 */
@@ -366,6 +467,7 @@ public class Zeichenmaschine extends Constants implements MouseInputListener, Ke
 		pmouseX = mouseX;
 		pmouseY = mouseY;
 
+		// TODO: Seems not right ...
 		java.awt.Point mouseLoc = MouseInfo.getPointerInfo().getLocation();
 		java.awt.Point compLoc = canvas.getLocationOnScreen();
 		mouseX = mouseLoc.x - compLoc.x;

src/schule/ngb/zm/shapes/Shape.java

@@ -121,7 +121,7 @@ public abstract class Shape extends FilledShape {
 	 * Bestimmt den Ankerpunkt der Form relativ zur oberen linken Ecke und
 	 * abhängig vom gesetzten {@link #setAnchor(Options.Direction) Anker}.
 	 */
-	public Point2D.Double getAnchorPoint() {
+	public Point2D.Double getAnchorPoint( Options.Direction anchor ) {
 		Point2D.Double anchorpoint = new Point2D.Double(0, 0);
 
 		double bHalf = getWidth() * .5, hHalf = getHeight() * .5;
@@ -203,18 +203,36 @@ public abstract class Shape extends FilledShape {
 		this.rotation = angle % 360;
 	}
 
+	public void rotate( Point2D center, double angle ) {
+		rotate(center.getX(), center.getY(), angle);
+	}
+
+	public void rotate( double x, double y, double angle ) {
+		this.rotation += angle % 360;
+
+		// Rotate x/y position
+		double x1 = this.x-x, y1 = this.y-y;
+
+		double rad = Math.toRadians(angle);
+		double x2 = x1 * Math.cos(rad) - y1 * Math.sin(rad);
+		double y2 = x1 * Math.sin(rad) + y1 * Math.cos(rad);
+
+		this.x = x2 + x;
+		this.y = y2 + y;
+	}
+
     /*public void shear( double dx, double dy ) {
         verzerrung.shear(dx, dy);
     }*/
 
 	public AffineTransform getTransform() {
-		Point2D.Double anchor = getAnchorPoint();
+		Point2D.Double anchorPoint = getAnchorPoint(this.anchor);
 
 		AffineTransform transform = new AffineTransform();
 		transform.translate(x, y);
 		transform.rotate(Math.toRadians(rotation));
 		//transform.scale(scale, scale);
-		transform.translate(-anchor.x, -anchor.y);
+		transform.translate(-anchorPoint.x, -anchorPoint.y);
 		return transform;
 	}
 

src/schule/ngb/zm/util/ImageLoader.java

@@ -1,7 +1,11 @@
 package schule.ngb.zm.util;
 
 import javax.imageio.ImageIO;
+import java.awt.Color;
+import java.awt.Graphics2D;
+import java.awt.Image;
 import java.awt.image.BufferedImage;
+import java.awt.image.RenderedImage;
 import java.io.File;
 import java.io.IOException;
 import java.net.URL;
@@ -138,4 +142,45 @@ public class ImageLoader {
 		cacheing = false;
 	}
 
+
+	public static void saveImage( Image image, File file ) throws IOException {
+		saveImage(image, file, false);
+	}
+
+	public static void saveImage( Image image, File file, boolean overwriteIfExists ) throws IOException {
+		BufferedImage outimage = new BufferedImage(image.getWidth(null), image.getHeight(null), BufferedImage.TYPE_INT_RGB);
+
+		Graphics2D g = outimage.createGraphics();
+		g.setColor(Color.WHITE);
+		g.fillRect(0, 0, outimage.getWidth(), outimage.getHeight());
+		g.drawImage(image, 0, 0, null);
+		g.dispose();
+
+		saveImage(outimage, file, overwriteIfExists);
+	}
+
+	public static void saveImage( BufferedImage image, File file ) throws IOException {
+		saveImage(image, file, false);
+	}
+
+	public static void saveImage( BufferedImage image, File file, boolean overwriteIfExists ) throws IOException {
+		if( file.isFile() ) {
+			if( !overwriteIfExists ) {
+				throw new IOException("File already exists. Delete target file before saving image.");
+			} else if( !file.canWrite() ) {
+				throw new IOException("File already exists and is not writeable. Change permissions before saving again.");
+			}
+		}
+
+		String filename = file.getName();
+		String formatName = "png";
+		if( filename.lastIndexOf('.') >= 0 ) {
+			formatName = filename.substring(filename.lastIndexOf('.') + 1);
+		} else {
+			file = new File(file.getAbsolutePath() + ".png");
+		}
+
+		ImageIO.write(image, formatName, file);
+	}
+
 }