preview

src/main/java/de/ph87/kindermalen/MotionListener.java

@@ -6,9 +6,12 @@ import java.util.function.Consumer;
 
 public class MotionListener implements MouseMotionListener {
 
+  private final Consumer<MouseEvent> onMove;
+
   private final Consumer<MouseEvent> onDrag;
 
-  public MotionListener(final Consumer<MouseEvent> onDrag) {
+  public MotionListener(final Consumer<MouseEvent> onMove, final Consumer<MouseEvent> onDrag) {
+    this.onMove = onMove;
     this.onDrag = onDrag;
   }
 
@@ -21,7 +24,9 @@ public class MotionListener implements MouseMotionListener {
 
   @Override
   public void mouseMoved(final MouseEvent e) {
-
+    if (onMove != null) {
+      onMove.accept(e);
+    }
   }
 
 }

src/main/java/de/ph87/kindermalen/drawing/DrawingPanel.java

@@ -8,6 +8,7 @@ import lombok.extern.slf4j.Slf4j;
 import javax.swing.*;
 import java.awt.*;
 import java.awt.event.MouseEvent;
+import java.awt.image.BufferedImage;
 
 @Slf4j
 public class DrawingPanel extends JPanel {
@@ -18,11 +19,18 @@ public class DrawingPanel extends JPanel {
 
   private Vector lastPoint = null;
 
+  private Point cursor = null;
+
   public DrawingPanel(final ToolBox toolBox, final Drawing drawing) {
     this.toolBox = toolBox;
     this.drawing = drawing;
     this.addMouseListener(new ClickListener(this::onPress, null));
-    this.addMouseMotionListener(new MotionListener(this::onDrag));
+    this.addMouseMotionListener(new MotionListener(this::onMove, this::onDrag));
+  }
+
+  private void onMove(final MouseEvent e) {
+    cursor = e.getPoint();
+    repaint();
   }
 
   private void onPress(final MouseEvent e) {
@@ -32,6 +40,7 @@ public class DrawingPanel extends JPanel {
   }
 
   private void onDrag(final MouseEvent e) {
+    cursor = e.getPoint();
     lastPoint = toolBox.getTool().apply(lastPoint, drawing.getCurrent().getCurrent(), new Vector(e.getPoint()));
     repaint();
   }
@@ -48,6 +57,11 @@ public class DrawingPanel extends JPanel {
     g.setColor(Color.white);
     g.fillRect(0, 0, drawing.getWidth(), drawing.getHeight());
     g.drawImage(drawing.getCurrent().getCurrent(), 0, 0, null);
+
+    final BufferedImage preview = toolBox.getTool().getPreview();
+    if (cursor != null && preview != null) {
+      g.drawImage(preview, cursor.x - preview.getWidth() / 2, cursor.y - preview.getHeight() / 2, null);
+    }
   }
 
 }

src/main/java/de/ph87/kindermalen/tool/Tool.java

@@ -16,4 +16,6 @@ public abstract class Tool {
 
   public abstract Vector apply(final Vector last, final BufferedImage image, final Vector point);
 
+  public abstract BufferedImage getPreview();
+
 }

src/main/java/de/ph87/kindermalen/tool/stamp/StampTool.java

@@ -110,4 +110,9 @@ public class StampTool extends Tool {
     destination.getGraphics().drawImage(prepared, point.intX() - prepared.getWidth() / 2, point.intY() - prepared.getHeight() / 2, null);
   }
 
+  @Override
+  public BufferedImage getPreview() {
+    return prepared;
+  }
+
 }