render + Sidebar DragDrop

src/main/java/de/ph87/electro/CONFIG.java

@@ -2,21 +2,25 @@ package de.ph87.electro;
 
 import java.awt.*;
 
+import static java.lang.Math.round;
+
 public class CONFIG {
 
+  public static final double VOLTAGE = 3.0;
+
   public static final int RASTER = 200;
 
-  public static final double HALF = 0.5;
+  public static final int HALF = (int) round(0.5 * RASTER);
 
-  public static final double FOURTH1 = 0.25;
+  public static final int FOURTH1 = (int) round(0.25 * RASTER);
 
-  public static final double FOURTH3 = 0.75;
+  public static final int FOURTH3 = (int) round(0.75 * RASTER);
 
-  public static final double JUNCTION_LEFT = 0.1;
+  public static final int JUNCTION_LEFT = (int) round(0.1 * RASTER);
 
-  public static final double JUNCTION_RIGHT = 0.9;
+  public static final int JUNCTION_RIGHT = (int) round(0.9 * RASTER);
 
-  public static final double JUNCTION_RADIUS = 0.05;
+  public static final int JUNCTION_RADIUS = (int) round(0.05 * RASTER);
 
   public static final Color PART_BACKGROUND = new Color(224, 224, 224);
 

src/main/java/de/ph87/electro/MathHelpers.java

@@ -0,0 +1,11 @@
+package de.ph87.electro;
+
+import java.awt.*;
+
+public class MathHelpers {
+
+  public static Point div(final Point p, final int div) {
+    return new Point(p.x / div, p.y / div);
+  }
+
+}

src/main/java/de/ph87/electro/Window.java

@@ -19,7 +19,7 @@ public class Window extends JFrame {
     c.weightx = 1;
     c.weighty = 1;
     c.fill = GridBagConstraints.BOTH;
-    add(new Sidebar(part -> circuit.getCircuit().add(part)), c);
+    add(new Sidebar(part -> circuit.getCircuit().getParts().add(part)), c);
 
     c = new GridBagConstraints();
     c.gridx = 1;

src/main/java/de/ph87/electro/circuit/Circuit.java

@@ -3,11 +3,13 @@ package de.ph87.electro.circuit;
 import de.ph87.electro.circuit.dto.CircuitDto;
 import de.ph87.electro.circuit.dto.PartDto;
 import de.ph87.electro.circuit.part.Junction;
+import de.ph87.electro.circuit.part.Orientation;
 import de.ph87.electro.circuit.part.Part;
 import de.ph87.electro.circuit.part.impl.*;
 import lombok.Getter;
 import lombok.NoArgsConstructor;
 
+import java.awt.*;
 import java.util.ArrayList;
 import java.util.List;
 import java.util.stream.Stream;
@@ -28,40 +30,33 @@ public class Circuit {
     parts.forEach(part -> part.link(junctions));
   }
 
-  public PartBattery addBattery(final String name, final int x, final int y, final int rotate, final double voltage) {
+  public PartBattery addBattery(final String name, final int x, final int y, final Orientation orientation, final double voltage) {
-    final PartBattery battery = new PartBattery(name, x, y, voltage);
+    final PartBattery battery = new PartBattery(name, new Point(x, y), orientation, voltage);
-    addAndRotate(battery, rotate);
+    parts.add(battery);
     return battery;
   }
 
-  private void addAndRotate(final Part part, final int rotate) {
+  public PartLight addLight(final String name, final int x, final int y, final Orientation orientation, final double maxVoltage) {
-    for (int i = 0; i < rotate % 4; i++) {
+    final PartLight light = new PartLight(name, new Point(x, y), orientation, maxVoltage);
-      part.clockwise();
+    parts.add(light);
-    }
-    add(part);
-  }
-
-  public PartLight addLight(final String name, final int x, final int y, final int rotate, final double maxVoltage) {
-    final PartLight light = new PartLight(name, x, y, maxVoltage);
-    addAndRotate(light, rotate);
     return light;
   }
 
-  public PartSwitch1x1 addSwitch1x1(final String name, final int x, final int y, final int rotate, final boolean state) {
+  public PartSwitch1x1 addSwitch1x1(final String name, final int x, final int y, final Orientation orientation, final boolean state) {
-    final PartSwitch1x1 switch1x1 = new PartSwitch1x1(name, x, y, state);
+    final PartSwitch1x1 switch1x1 = new PartSwitch1x1(name, new Point(x, y), orientation, state);
-    addAndRotate(switch1x1, rotate);
+    parts.add(switch1x1);
     return switch1x1;
   }
 
-  public PartSwitch1x2 addSwitch1x2(final String name, final int x, final int y, final int rotate, final boolean state) {
+  public PartSwitch1x2 addSwitch1x2(final String name, final int x, final int y, final Orientation orientation, final boolean state) {
-    final PartSwitch1x2 switch1x2 = new PartSwitch1x2(name, x, y, state);
+    final PartSwitch1x2 switch1x2 = new PartSwitch1x2(name, new Point(x, y), orientation, state);
-    addAndRotate(switch1x2, rotate);
+    parts.add(switch1x2);
     return switch1x2;
   }
 
-  public PartSwitchCross addSwitchCross(final String name, final int x, final int y, final int rotate, final boolean state) {
+  public PartSwitchCross addSwitchCross(final String name, final int x, final int y, final Orientation orientation, final boolean state) {
-    final PartSwitchCross switchCross = new PartSwitchCross(name, x, y, state);
+    final PartSwitchCross switchCross = new PartSwitchCross(name, new Point(x, y), orientation, state);
-    addAndRotate(switchCross, rotate);
+    parts.add(switchCross);
     return switchCross;
   }
 
@@ -70,14 +65,14 @@ public class Circuit {
     b.getDestinations().add(a);
   }
 
-  public void add(final Part part) {
-    parts.add(part);
-    evaluate();
-  }
-
   public void evaluate() {
     parts.forEach(Part::reset);
     streamBatteries().forEach(PartBattery::startPropagation);
+    render();
+  }
+
+  public void render() {
+    parts.forEach(Part::render);
   }
 
   private Stream<PartBattery> streamBatteries() {
@@ -98,4 +93,9 @@ public class Circuit {
     return wires;
   }
 
+  public void add(final Part part) {
+    parts.add(part);
+    evaluate();
+  }
+
 }

src/main/java/de/ph87/electro/circuit/CircuitPanel.java

@@ -1,23 +1,32 @@
 package de.ph87.electro.circuit;
 
 import de.ph87.electro.circuit.part.Part;
+import de.ph87.electro.circuit.part.impl.*;
 import de.ph87.electro.demo.DemoAll;
 import lombok.Getter;
+import lombok.extern.slf4j.Slf4j;
 
 import javax.swing.*;
 import java.awt.*;
+import java.awt.datatransfer.DataFlavor;
+import java.awt.datatransfer.Transferable;
+import java.awt.dnd.DnDConstants;
+import java.awt.dnd.DropTarget;
+import java.awt.dnd.DropTargetDropEvent;
 import java.awt.event.MouseAdapter;
 import java.awt.event.MouseEvent;
 import java.util.Optional;
 
 import static de.ph87.electro.CONFIG.*;
+import static de.ph87.electro.MathHelpers.div;
 import static java.awt.event.MouseEvent.BUTTON1;
 import static java.awt.event.MouseEvent.BUTTON3;
 
+@Slf4j
 public class CircuitPanel extends JPanel {
 
   @Getter
-  private Circuit circuit = new Circuit();
+  private final Circuit circuit = DemoAll.create();
 
   private Part dragPart = null;
 
@@ -26,64 +35,43 @@ public class CircuitPanel extends JPanel {
   private Point dragOffset = null;
 
   public CircuitPanel() {
-    final MouseAdapter listener = new MouseAdapter() {
+    final MouseAdapter listener = new MyMouseAdapter();
-
-      @Override
-      public void mouseClicked(final MouseEvent e) {
-        final int x = e.getX() / RASTER;
-        final int y = e.getY() / RASTER;
-        final Optional<Part> partOptional = circuit.getParts().stream().filter(p -> p.getX() == x && p.getY() == y).findFirst();
-        switch (e.getButton()) {
-          case BUTTON1:
-            partOptional.ifPresent(part -> {
-              part.click();
-              circuit.evaluate();
-              repaint();
-            });
-            break;
-          case BUTTON3:
-            partOptional.ifPresent(part -> {
-              part.clockwise();
-              repaint();
-            });
-            break;
-        }
-      }
-
-      @Override
-      public void mousePressed(final MouseEvent e) {
-        final int x = e.getX() / RASTER;
-        final int y = e.getY() / RASTER;
-        dragOffset = new Point(RASTER / 2, RASTER / 2);
-        dragPart = circuit.getParts().stream().filter(p -> p.getX() == x && p.getY() == y).findFirst().orElse(null);
-      }
-
-      @Override
-      public void mouseDragged(final MouseEvent e) {
-        if (dragPart != null) {
-          dragPoint = e.getPoint();
-          repaint();
-        }
-      }
-
-      @Override
-      public void mouseReleased(final MouseEvent e) {
-        if (dragPart != null) {
-          final int x = e.getX() / RASTER;
-          final int y = e.getY() / RASTER;
-          dragPart.setX(x);
-          dragPart.setY(y);
-          dragPart = null;
-          dragPoint = null;
-          dragOffset = null;
-          repaint();
-        }
-      }
-
-    };
     addMouseListener(listener);
     addMouseMotionListener(listener);
-    circuit = DemoAll.create();
+    setDropTarget(new DropTarget() {
+
+      @Override
+      public void drop(final DropTargetDropEvent event) {
+        log.info("drop");
+        try {
+          final Transferable transferable = event.getTransferable();
+          if (transferable.isDataFlavorSupported(DataFlavor.stringFlavor)) {
+            event.acceptDrop(DnDConstants.ACTION_COPY);
+            final Point raster = div(event.getLocation(), RASTER);
+            final String data = (String) transferable.getTransferData(DataFlavor.stringFlavor);
+            if (data.equals(PartBattery.class.getSimpleName())) {
+              circuit.add(new PartBattery(raster));
+            } else if (data.equals(PartLight.class.getSimpleName())) {
+              circuit.add(new PartLight(raster));
+            } else if (data.equals(PartSwitch1x1.class.getSimpleName())) {
+              circuit.add(new PartSwitch1x1(raster));
+            } else if (data.equals(PartSwitch1x2.class.getSimpleName())) {
+              circuit.add(new PartSwitch1x2(raster));
+            } else if (data.equals(PartSwitchCross.class.getSimpleName())) {
+              circuit.add(new PartSwitchCross(raster));
+            }
+            repaint();
+            event.dropComplete(true);
+          } else {
+            event.rejectDrop();
+          }
+        } catch (Exception e) {
+          log.error(e.toString());
+          event.rejectDrop();
+        }
+      }
+
+    });
   }
 
   @Override
@@ -95,10 +83,7 @@ public class CircuitPanel extends JPanel {
     drawParts(g);
     drawRaster(g, w, h);
     drawWires(g);
-    if (dragPart != null && dragPoint != null) {
+    drawDrag(g);
-      g.setColor(new Color(192, 192, 192, 128));
-      g.fillRect(dragPoint.x - dragOffset.x, dragPoint.y - dragOffset.y, RASTER, RASTER);
-    }
   }
 
   private void drawBack(final Graphics2D g, final int w, final int h) {
@@ -123,19 +108,76 @@ public class CircuitPanel extends JPanel {
 
   private void drawWires(final Graphics2D g) {
     for (final Wire wire : circuit.getWires()) {
-      final int x0 = wire.getA().getAbsoluteX();
+      final Point a = wire.getA().getAbsolute();
-      final int y0 = wire.getA().getAbsoluteY();
+      final Point b = wire.getB().getAbsolute();
-      final int x1 = wire.getB().getAbsoluteX();
-      final int y1 = wire.getB().getAbsoluteY();
 
       g.setColor(Color.BLACK);
       g.setStroke(WIRE_STROKE_BACK);
-      g.drawLine(x0, y0, x1, y1);
+      g.drawLine(a.x, a.y, b.x, b.y);
 
       g.setColor(wire.getA().getColor());
       g.setStroke(WIRE_STROKE);
-      g.drawLine(x0, y0, x1, y1);
+      g.drawLine(a.x, a.y, b.x, b.y);
     }
   }
 
+  private void drawDrag(final Graphics2D g) {
+    if (dragPart != null && dragPoint != null) {
+      g.setColor(new Color(192, 192, 192, 128));
+      g.fillRect(dragPoint.x - dragOffset.x, dragPoint.y - dragOffset.y, RASTER, RASTER);
+    }
+  }
+
+  private class MyMouseAdapter extends MouseAdapter {
+
+    @Override
+    public void mouseClicked(final MouseEvent e) {
+      final Point cell = div(e.getPoint(), RASTER);
+      final Optional<Part> partOptional = circuit.getParts().stream().filter(p -> p.getPosition().equals(cell)).findFirst();
+      switch (e.getButton()) {
+        case BUTTON1:
+          partOptional.ifPresent(part -> {
+            part.click();
+            circuit.evaluate();
+            repaint();
+          });
+          break;
+        case BUTTON3:
+          partOptional.ifPresent(part -> {
+            part.clockwise();
+            circuit.render();
+            repaint();
+          });
+          break;
+      }
+    }
+
+    @Override
+    public void mousePressed(final MouseEvent e) {
+      final Point cell = div(e.getPoint(), RASTER);
+      dragOffset = new Point(HALF, HALF);
+      dragPart = circuit.getParts().stream().filter(p -> p.getPosition().equals(cell)).findFirst().orElse(null);
+    }
+
+    @Override
+    public void mouseDragged(final MouseEvent e) {
+      if (dragPart != null) {
+        dragPoint = e.getPoint();
+        repaint();
+      }
+    }
+
+    @Override
+    public void mouseReleased(final MouseEvent e) {
+      if (dragPart != null) {
+        dragPart.setPosition(div(e.getPoint(), RASTER));
+        dragPart = null;
+        dragPoint = null;
+        dragOffset = null;
+        repaint();
+      }
+    }
+
+  }
+
 }

src/main/java/de/ph87/electro/circuit/dto/JunctionDto.java

@@ -16,17 +16,11 @@ public class JunctionDto {
 
   private String name;
 
-  private double x;
-
-  private double y;
-
   private List<String> destinations;
 
   public JunctionDto(final Junction junction) {
     this.uuid = junction.getUuid();
     this.name = junction.getName();
-    this.x = junction.getX();
-    this.y = junction.getY();
     this.destinations = junction.getDestinations().stream().map(Junction::getUuid).toList();
   }
 

src/main/java/de/ph87/electro/circuit/dto/PartDto.java

@@ -8,6 +8,7 @@ import lombok.Getter;
 import lombok.NoArgsConstructor;
 import lombok.ToString;
 
+import java.awt.*;
 import java.util.List;
 
 @Getter
@@ -20,9 +21,7 @@ public class PartDto {
 
   private String name;
 
-  private int x;
+  private Point position;
-
-  private int y;
 
   private Orientation orientation;
 
@@ -31,8 +30,7 @@ public class PartDto {
   protected PartDto(final Part part) {
     this.uuid = part.getUuid();
     this.name = part.getName();
-    this.x = part.getX();
+    this.position = part.getPosition();
-    this.y = part.getY();
     this.orientation = part.getOrientation();
     this.junctions = part.getJunctions().stream().map(JunctionDto::new).toList();
   }

src/main/java/de/ph87/electro/circuit/part/Junction.java

@@ -13,7 +13,6 @@ import java.util.Set;
 import java.util.UUID;
 
 import static de.ph87.electro.CONFIG.*;
-import static java.lang.Math.round;
 
 @Getter
 @ToString(onlyExplicitlyIncluded = true)
@@ -29,9 +28,7 @@ public class Junction {
   @ToString.Include
   private final String name;
 
-  private double x;
+  private final Point position;
-
-  private double y;
 
   private final Set<Junction> destinations = new HashSet<>();
 
@@ -47,21 +44,19 @@ public class Junction {
     return destinations.stream().map(Junction::getUuid).toList();
   }
 
-  public Junction(final Part owner, final String name, final double x, final double y) {
+  public Junction(final Part owner, final String name, final Point position) {
     this.uuid = UUID.randomUUID().toString();
     this.owner = owner;
     this.name = name;
-    this.x = x;
+    this.position = position;
-    this.y = y;
     this._dto = null;
   }
 
-  public Junction(final Part owner, final JunctionDto dto) {
+  public Junction(final Part owner, final JunctionDto dto, final Point position) {
     this.uuid = dto.getUuid();
     this.owner = owner;
     this.name = dto.getName();
-    this.x = dto.getX();
+    this.position = position;
-    this.y = dto.getY();
     this._dto = dto;
   }
 
@@ -100,23 +95,16 @@ public class Junction {
     throw new ShortCircuit();
   }
 
-  @SuppressWarnings("SuspiciousNameCombination")
+  public void render(final Graphics2D g) {
-  public void rotate() {
+    owner.circle(g, position.x, position.y, JUNCTION_RADIUS, Color.BLACK, NORMAL_STROKE, color);
-    final double oldX = x;
-    x = 1 - y;
-    y = oldX;
   }
 
-  public void paint(final Graphics2D g) {
+  public Point getAbsolute() {
-    owner.circle(g, x, y, JUNCTION_RADIUS, Color.BLACK, NORMAL_STROKE, color);
+    return owner.translate(getRotated());
   }
 
-  public int getAbsoluteX() {
+  private Point getRotated() {
-    return (int) round((owner.x + x) * RASTER);
+    return owner.getOrientation().rotate(position);
-  }
-
-  public int getAbsoluteY() {
-    return (int) round((owner.y + y) * RASTER);
   }
 
 }

src/main/java/de/ph87/electro/circuit/part/Orientation.java

@@ -1,28 +1,29 @@
 package de.ph87.electro.circuit.part;
 
-import java.awt.geom.Point2D;
+import java.awt.*;
 import java.util.function.Function;
 
+import static de.ph87.electro.CONFIG.RASTER;
 import static java.lang.Math.PI;
 
 @SuppressWarnings("SuspiciousNameCombination")
 public enum Orientation {
-  R0(0, p -> new Point2D.Double(p.x, p.y)),
+  R0(0, p -> new Point(p.x, p.y)),
-  R1(1, p -> new Point2D.Double(1 - p.y, p.x)),
+  R1(1, p -> new Point(RASTER - p.y, p.x)),
-  R2(2, p -> new Point2D.Double(1 - p.x, 1 - p.y)),
+  R2(2, p -> new Point(RASTER - p.x, RASTER - p.y)),
-  R3(3, p -> new Point2D.Double(p.y, 1 - p.x)),
+  R3(3, p -> new Point(p.y, RASTER - p.x)),
   ;
 
-  private final Function<Point2D.Double, Point2D.Double> map;
+  private final Function<Point, Point> map;
 
   private final int deg90;
 
-  Orientation(final int deg90, final Function<Point2D.Double, Point2D.Double> map) {
+  Orientation(final int deg90, final Function<Point, Point> rotate) {
     this.deg90 = deg90;
-    this.map = map;
+    this.map = rotate;
   }
 
-  public Point2D.Double map(final Point2D.Double p) {
+  public Point rotate(final Point p) {
     return map.apply(p);
   }
 

src/main/java/de/ph87/electro/circuit/part/Part.java

@@ -13,8 +13,7 @@ import java.util.ArrayList;
 import java.util.List;
 import java.util.UUID;
 
-import static de.ph87.electro.CONFIG.PART_BACKGROUND;
+import static de.ph87.electro.CONFIG.*;
-import static de.ph87.electro.CONFIG.RASTER;
 import static java.lang.Math.round;
 
 @Getter
@@ -28,26 +27,25 @@ public abstract class Part {
   @ToString.Include
   protected String name;
 
-  protected int x;
+  protected Point position;
 
-  protected int y;
+  private Orientation orientation;
 
-  protected Orientation orientation = Orientation.R0;
+  private final List<Junction> junctions = new ArrayList<>();
 
-  protected final List<Junction> junctions = new ArrayList<>();
+  private final BufferedImage render = new BufferedImage(RASTER, RASTER, BufferedImage.TYPE_INT_ARGB);
 
-  protected Part(final String name, final int x, final int y) {
+  protected Part(final String name, final Point position, final Orientation orientation) {
     this.uuid = UUID.randomUUID().toString();
     this.name = name;
-    this.x = x;
+    this.position = position;
-    this.y = y;
+    this.orientation = orientation;
   }
 
   protected Part(final PartDto dto) {
     this.uuid = dto.getUuid();
     this.name = dto.getName();
-    this.x = dto.getX();
+    this.position = dto.getPosition();
-    this.y = dto.getY();
     this.orientation = dto.getOrientation();
   }
 
@@ -55,30 +53,52 @@ public abstract class Part {
     junctions.forEach(junction -> junction.link(junctions));
   }
 
+  protected Junction newJunction(final Part owner, final String name, final int x, final int y) {
+    return addJunction(new Junction(owner, name, new Point(x, y)));
+  }
+
+  protected Junction newJunction(final Part owner, final JunctionDto dto, final int x, final int y) {
+    return addJunction(new Junction(owner, dto, new Point(x, y)));
+  }
+
+  private Junction addJunction(final Junction junction) {
+    junctions.add(junction);
+    return junction;
+  }
+
   public void reset() {
     junctions.forEach(Junction::reset);
   }
 
+  public void render() {
+    final Graphics2D g = (Graphics2D) render.getGraphics();
+    g.rotate(orientation.getTheta(), HALF, HALF);
+    rect(g, 0, 0, RASTER, RASTER, null, null, PART_BACKGROUND);
+    _render(g);
+    junctions.forEach(junction -> junction.render(g));
+  }
+
   public void paint(final Graphics2D g) {
-    rect(g, 0, 0, 1, 1, null, null, PART_BACKGROUND);
+    g.drawImage(render, position.x * RASTER, position.y * RASTER, null);
-    _paint(g);
-    junctions.forEach(junction -> junction.paint(g));
   }
 
   public void clockwise() {
     orientation = orientation.clockwise();
-    junctions.forEach(Junction::rotate);
   }
 
-  public void line(final Graphics2D g, final Junction common0, final Junction output0, final Color color, final BasicStroke stroke) {
+  public void line(final Graphics2D g, final Junction junction0, final Junction junction1, final Color color, final BasicStroke stroke) {
-    line(g, common0.getX(), common0.getY(), output0.getX(), output0.getY(), color, stroke);
+    line(g, junction0.getPosition().x, junction0.getPosition().y, junction1.getPosition().x, junction1.getPosition().y, color, stroke);
+  }
+
+  public void line(final Graphics2D g, final Junction junction0, final double x1, final double y1, final Color color, final BasicStroke stroke) {
+    line(g, junction0.getPosition().x, junction0.getPosition().y, x1, y1, color, stroke);
   }
 
   public void line(final Graphics2D g, final double x0, final double y0, final double x1, final double y1, final Color color, final Stroke stroke) {
-    final int _x0 = (int) round((x + x0) * RASTER);
+    final int _x0 = (int) round(position.x + x0);
-    final int _y0 = (int) round((y + y0) * RASTER);
+    final int _y0 = (int) round(position.y + y0);
-    final int _x1 = (int) round((x + x1) * RASTER);
+    final int _x1 = (int) round(position.x + x1);
-    final int _y1 = (int) round((y + y1) * RASTER);
+    final int _y1 = (int) round(position.y + y1);
     if (color != null) {
       g.setColor(color);
     }
@@ -89,10 +109,10 @@ public abstract class Part {
   }
 
   public void rect(final Graphics2D g, final double x, final double y, final double w, final double h, final Color border, final Stroke stroke, final Color fill) {
-    final int _x = (int) round((this.x + x) * RASTER);
+    final int _x = (int) round(position.x + x);
-    final int _y = (int) round((this.y + y) * RASTER);
+    final int _y = (int) round(position.y + y);
-    final int _w = (int) round(w * RASTER);
+    final int _w = (int) round(w);
-    final int _h = (int) round(h * RASTER);
+    final int _h = (int) round(h);
     if (fill != null) {
       g.setColor(fill);
       g.fillRect(_x, _y, _w, _h);
@@ -104,16 +124,10 @@ public abstract class Part {
     }
   }
 
-  public void img(final Graphics2D g, final BufferedImage img, final double x, final double y) {
-    final int _x = (int) round((this.x + x) * RASTER);
-    final int _y = (int) round((this.y + y) * RASTER);
-    g.drawImage(img, _x, _y, null);
-  }
-
   public void circle(final Graphics2D g, final double x, final double y, final double radius, final Color border, final Stroke stroke, final Color fill) {
-    final int _x = (int) round((this.x + x - radius) * RASTER);
+    final int _x = (int) round(position.x + x - radius);
-    final int _y = (int) round((this.y + y - radius) * RASTER);
+    final int _y = (int) round(position.y + y - radius);
-    final int diameter = (int) round(radius * RASTER * 2);
+    final int diameter = (int) round(radius * 2);
     if (fill != null) {
       g.setColor(fill);
       g.fillArc(_x, _y, diameter, diameter, 0, 360);
@@ -129,7 +143,9 @@ public abstract class Part {
 
   public abstract void propagate(final Junction source) throws ShortCircuit;
 
-  protected abstract void _paint(final Graphics2D g);
+  protected abstract void _render(final Graphics2D g);
+
+  public abstract Part duplicate(final Point position);
 
   public static Part of(final PartDto abstractDto) {
     return switch (abstractDto) {
@@ -142,6 +158,11 @@ public abstract class Part {
     };
   }
 
-  public abstract Part duplicate(final int x, final int y);
+  public Point translate(final Point p) {
+    return new Point(
+      p.x + position.x * RASTER,
+      p.y + position.y * RASTER
+    );
+  }
 
 }

src/main/java/de/ph87/electro/circuit/part/PartOther.java

@@ -1,14 +1,16 @@
 package de.ph87.electro.circuit.part;
 
-import de.ph87.electro.circuit.dto.PartLightDto;
+import de.ph87.electro.circuit.dto.PartDto;
+
+import java.awt.*;
 
 public abstract class PartOther extends Part {
 
-  protected PartOther(final String name, final int x, final int y) {
+  protected PartOther(final String name, final Point position, final Orientation orientation) {
-    super(name, x, y);
+    super(name, position, orientation);
   }
 
-  protected PartOther(final PartLightDto dto) {
+  protected PartOther(final PartDto dto) {
     super(dto);
   }
 

src/main/java/de/ph87/electro/circuit/part/impl/PartBattery.java

@@ -3,13 +3,13 @@ package de.ph87.electro.circuit.part.impl;
 import de.ph87.electro.circuit.ShortCircuit;
 import de.ph87.electro.circuit.dto.PartBatteryDto;
 import de.ph87.electro.circuit.part.Junction;
+import de.ph87.electro.circuit.part.Orientation;
 import de.ph87.electro.circuit.part.Part;
 import lombok.Getter;
 import lombok.Setter;
 import lombok.ToString;
 
 import java.awt.*;
-import java.awt.image.BufferedImage;
 
 import static de.ph87.electro.CONFIG.*;
 
@@ -17,15 +17,15 @@ import static de.ph87.electro.CONFIG.*;
 @ToString(callSuper = true)
 public class PartBattery extends Part {
 
-  private static final double MINUS_W = 0.1;
+  private static final double MINUS_W = 0.1 * RASTER;
 
-  private static final double MINUS_H = 0.3;
+  private static final double MINUS_H = 0.3 * RASTER;
 
-  private static final double GAP = 0.05;
+  private static final double GAP = 0.05 * RASTER;
 
-  private static final double PLUS_W = 0.02;
+  private static final double PLUS_W = 0.02 * RASTER;
 
-  private static final double PLUS_H = 0.6;
+  private static final double PLUS_H = 0.6 * RASTER;
 
   private final Junction minus;
 
@@ -36,21 +36,21 @@ public class PartBattery extends Part {
 
   private ShortCircuit shortCircuit = null;
 
-  public PartBattery(final String name, final int x, final int y, final double initialVoltage) {
+  public PartBattery(final Point position) {
-    super(name, x, y);
+    this("Batterie", position, Orientation.R0, VOLTAGE);
-    minus = new Junction(this, "-", JUNCTION_LEFT, HALF);
+  }
-    plus = new Junction(this, "+", JUNCTION_RIGHT, HALF);
+
-    junctions.add(minus);
+  public PartBattery(final String name, final Point position, final Orientation orientation, final double initialVoltage) {
-    junctions.add(plus);
+    super(name, position, orientation);
+    minus = newJunction(this, "-", JUNCTION_LEFT, HALF);
+    plus = newJunction(this, "+", JUNCTION_RIGHT, HALF);
     voltage = initialVoltage;
   }
 
   public PartBattery(final PartBatteryDto dto) {
     super(dto);
-    minus = new Junction(this, dto.getMinus());
+    minus = newJunction(this, dto.getMinus(), JUNCTION_LEFT, HALF);
-    plus = new Junction(this, dto.getPlus());
+    plus = newJunction(this, dto.getPlus(), JUNCTION_RIGHT, HALF);
-    junctions.add(minus);
-    junctions.add(plus);
     voltage = dto.getVoltage();
   }
 
@@ -75,22 +75,16 @@ public class PartBattery extends Part {
   }
 
   @Override
-  protected void _paint(final Graphics2D g) {
+  protected void _render(final Graphics2D g) {
-    final BufferedImage img = new BufferedImage(RASTER, RASTER, BufferedImage.TYPE_INT_ARGB);
+    line(g, JUNCTION_LEFT, HALF, HALF - GAP / 2 - MINUS_W / 2, HALF, Color.BLACK, SYMBOL_STROKE);
-    final Graphics2D x = (Graphics2D) img.getGraphics();
+    line(g, HALF + GAP / 2 + PLUS_W / 2, HALF, JUNCTION_RIGHT, HALF, Color.BLACK, SYMBOL_STROKE);
-    x.translate(RASTER / 2, RASTER / 2);
+    rect(g, HALF - MINUS_W - GAP / 2, HALF - MINUS_H / 2, MINUS_W, MINUS_H, null, null, Color.BLACK);
-    x.rotate(orientation.getTheta());
+    rect(g, HALF + GAP / 2, HALF - PLUS_H / 2, PLUS_W, PLUS_H, null, null, Color.BLACK);
-    x.translate(-RASTER / 2, -RASTER / 2);
-    line(x, JUNCTION_LEFT, HALF, HALF - GAP / 2 - MINUS_W / 2, HALF, Color.BLACK, SYMBOL_STROKE);
-    line(x, HALF + GAP / 2 + PLUS_W / 2, HALF, JUNCTION_RIGHT, HALF, Color.BLACK, SYMBOL_STROKE);
-    rect(x, HALF - MINUS_W - GAP / 2, HALF - MINUS_H / 2, MINUS_W, MINUS_H, null, null, Color.BLACK);
-    rect(x, HALF + GAP / 2, HALF - PLUS_H / 2, PLUS_W, PLUS_H, null, null, Color.BLACK);
-    img(g, img, 0, 0);
   }
 
   @Override
-  public PartBattery duplicate(final int x, final int y) {
+  public PartBattery duplicate(final Point position) {
-    return new PartBattery(name, x, y, voltage);
+    return new PartBattery(name, position, getOrientation(), voltage);
   }
 
   @Override

src/main/java/de/ph87/electro/circuit/part/impl/PartLight.java

@@ -2,6 +2,7 @@ package de.ph87.electro.circuit.part.impl;
 
 import de.ph87.electro.circuit.dto.PartLightDto;
 import de.ph87.electro.circuit.part.Junction;
+import de.ph87.electro.circuit.part.Orientation;
 import de.ph87.electro.circuit.part.PartOther;
 import lombok.Getter;
 import lombok.ToString;
@@ -18,17 +19,17 @@ public class PartLight extends PartOther {
 
   private static final Color COLOR_DEFECT = new Color(255, 0, 234);
 
-  private static final double MINUS_W = 0.1;
+  private static final int MINUS_W = (int) round(0.1 * RASTER);
 
-  private static final double MINUS_H = 0.3;
+  private static final int MINUS_H = (int) round(0.3 * RASTER);
 
-  private static final double GAP = 0.05;
+  private static final int GAP = (int) round(0.05 * RASTER);
 
-  private static final double PLUS_W = 0.02;
+  private static final int PLUS_W = (int) round(0.02 * RASTER);
 
-  private static final double PLUS_H = 0.6;
+  private static final int PLUS_H = (int) round(0.6 * RASTER);
 
-  private static final double BULB_RADIUS = 0.25;
+  private static final int BULB_RADIUS = (int) round(0.25 * RASTER);
 
   private final Junction pin0;
 
@@ -42,21 +43,21 @@ public class PartLight extends PartOther {
 
   private Color color;
 
-  public PartLight(final String name, final int x, final int y, final double maxVoltage) {
+  public PartLight(final Point position) {
-    super(name, x, y);
+    this("Licht", position, Orientation.R0, VOLTAGE);
-    pin0 = new Junction(this, "", JUNCTION_LEFT, HALF);
+  }
-    pin1 = new Junction(this, "", JUNCTION_RIGHT, HALF);
+
-    junctions.add(pin0);
+  public PartLight(final String name, final Point position, final Orientation orientation, final double maxVoltage) {
-    junctions.add(pin1);
+    super(name, position, orientation);
+    pin0 = newJunction(this, "", JUNCTION_LEFT, HALF);
+    pin1 = newJunction(this, "", JUNCTION_RIGHT, HALF);
     this.maxVoltage = maxVoltage;
   }
 
   public PartLight(final PartLightDto dto) {
     super(dto);
-    pin0 = new Junction(this, dto.getMinus());
+    pin0 = newJunction(this, dto.getMinus(), JUNCTION_LEFT, HALF);
-    pin1 = new Junction(this, dto.getPlus());
+    pin1 = newJunction(this, dto.getPlus(), JUNCTION_LEFT, HALF);
-    junctions.add(pin0);
-    junctions.add(pin1);
     maxVoltage = dto.getMaxVoltage();
     defect = dto.isDefect();
   }
@@ -80,18 +81,18 @@ public class PartLight extends PartOther {
   }
 
   @Override
-  protected void _paint(final Graphics2D g) {
+  protected void _render(final Graphics2D g) {
     line(g, pin0, pin1, Color.BLACK, SYMBOL_STROKE);
     circle(g, HALF, HALF, BULB_RADIUS, Color.BLACK, SYMBOL_STROKE, color);
 
-    final double diag = 0.33;
+    final double diag = 0.33 * RASTER;
-    line(g, diag, diag, 1 - diag, 1 - diag, Color.BLACK, SYMBOL_STROKE);
+    line(g, diag, diag, RASTER - diag, RASTER - diag, Color.BLACK, SYMBOL_STROKE);
-    line(g, diag, 1 - diag, 1 - diag, diag, Color.BLACK, SYMBOL_STROKE);
+    line(g, diag, RASTER - diag, RASTER - diag, diag, Color.BLACK, SYMBOL_STROKE);
   }
 
   @Override
-  public PartLight duplicate(final int x, final int y) {
+  public PartLight duplicate(final Point position) {
-    return new PartLight(name, x, y, maxVoltage);
+    return new PartLight(name, position, getOrientation(), maxVoltage);
   }
 
   @Override

src/main/java/de/ph87/electro/circuit/part/impl/PartSwitch1x1.java

@@ -3,6 +3,7 @@ package de.ph87.electro.circuit.part.impl;
 import de.ph87.electro.circuit.ShortCircuit;
 import de.ph87.electro.circuit.dto.PartSwitch1x1Dto;
 import de.ph87.electro.circuit.part.Junction;
+import de.ph87.electro.circuit.part.Orientation;
 import de.ph87.electro.circuit.part.PartOther;
 import lombok.Getter;
 import lombok.Setter;
@@ -23,21 +24,21 @@ public class PartSwitch1x1 extends PartOther {
   @Setter
   private boolean state;
 
-  public PartSwitch1x1(final String name, final int x, final int y, final boolean state) {
+  public PartSwitch1x1(final Point position) {
-    super(name, x, y);
+    this("Ausschalter", position, Orientation.R0, false);
-    common = new Junction(this, "", JUNCTION_LEFT, HALF);
+  }
-    output = new Junction(this, "", JUNCTION_RIGHT, HALF);
+
-    junctions.add(common);
+  public PartSwitch1x1(final String name, final Point position, final Orientation orientation, final boolean state) {
-    junctions.add(output);
+    super(name, position, orientation);
+    common = newJunction(this, "", JUNCTION_LEFT, HALF);
+    output = newJunction(this, "", JUNCTION_RIGHT, HALF);
     this.state = state;
   }
 
   public PartSwitch1x1(final PartSwitch1x1Dto dto) {
-    super(dto.getName(), dto.getX(), dto.getY());
+    super(dto);
-    common = new Junction(this, dto.getCommon());
+    common = newJunction(this, dto.getCommon(), JUNCTION_LEFT, HALF);
-    output = new Junction(this, dto.getOutput());
+    output = newJunction(this, dto.getOutput(), JUNCTION_RIGHT, HALF);
-    junctions.add(common);
-    junctions.add(output);
     state = dto.isState();
   }
 
@@ -55,9 +56,9 @@ public class PartSwitch1x1 extends PartOther {
   }
 
   @Override
-  protected void _paint(final Graphics2D g) {
+  protected void _render(final Graphics2D g) {
     if (!state) {
-      line(g, common.getX(), common.getY(), JUNCTION_RIGHT, FOURTH1, common.getColor(), SWITCH_STROKE);
+      line(g, common, JUNCTION_RIGHT, FOURTH1, common.getColor(), SWITCH_STROKE);
     } else {
       line(g, common, output, common.getColor(), SWITCH_STROKE);
     }
@@ -69,8 +70,8 @@ public class PartSwitch1x1 extends PartOther {
   }
 
   @Override
-  public PartSwitch1x1 duplicate(final int x, final int y) {
+  public PartSwitch1x1 duplicate(final Point position) {
-    return new PartSwitch1x1(name, x, y, state);
+    return new PartSwitch1x1(name, position, getOrientation(), state);
   }
 
 }

src/main/java/de/ph87/electro/circuit/part/impl/PartSwitch1x2.java

@@ -3,6 +3,7 @@ package de.ph87.electro.circuit.part.impl;
 import de.ph87.electro.circuit.ShortCircuit;
 import de.ph87.electro.circuit.dto.PartSwitch1x2Dto;
 import de.ph87.electro.circuit.part.Junction;
+import de.ph87.electro.circuit.part.Orientation;
 import de.ph87.electro.circuit.part.PartOther;
 import lombok.Getter;
 import lombok.Setter;
@@ -25,25 +26,23 @@ public class PartSwitch1x2 extends PartOther {
   @Setter
   private boolean state;
 
-  public PartSwitch1x2(final String name, final int x, final int y, final boolean state) {
+  public PartSwitch1x2(final Point position) {
-    super(name, x, y);
+    this("Wechselschalter", position, Orientation.R0, false);
-    common = new Junction(this, "", JUNCTION_LEFT, HALF);
+  }
-    output0 = new Junction(this, "", JUNCTION_RIGHT, FOURTH1);
+
-    output1 = new Junction(this, "", JUNCTION_RIGHT, FOURTH3);
+  public PartSwitch1x2(final String name, final Point position, final Orientation orientation, final boolean state) {
-    junctions.add(common);
+    super(name, position, orientation);
-    junctions.add(output0);
+    common = newJunction(this, "", JUNCTION_LEFT, HALF);
-    junctions.add(output1);
+    output0 = newJunction(this, "", JUNCTION_RIGHT, FOURTH1);
+    output1 = newJunction(this, "", JUNCTION_RIGHT, FOURTH3);
     this.state = state;
   }
 
   public PartSwitch1x2(final PartSwitch1x2Dto dto) {
-    super(dto.getName(), dto.getX(), dto.getY());
+    super(dto);
-    common = new Junction(this, dto.getCommon());
+    common = newJunction(this, dto.getCommon(), JUNCTION_LEFT, HALF);
-    output0 = new Junction(this, dto.getOutput0());
+    output0 = newJunction(this, dto.getOutput0(), JUNCTION_RIGHT, FOURTH1);
-    output1 = new Junction(this, dto.getOutput1());
+    output1 = newJunction(this, dto.getOutput1(), JUNCTION_RIGHT, FOURTH3);
-    junctions.add(common);
-    junctions.add(output0);
-    junctions.add(output1);
     state = dto.isState();
   }
 
@@ -67,7 +66,7 @@ public class PartSwitch1x2 extends PartOther {
   }
 
   @Override
-  protected void _paint(final Graphics2D g) {
+  protected void _render(final Graphics2D g) {
     if (!state) {
       line(g, common, output0, common.getColor(), SWITCH_STROKE);
     } else {
@@ -81,8 +80,8 @@ public class PartSwitch1x2 extends PartOther {
   }
 
   @Override
-  public PartSwitch1x2 duplicate(final int x, final int y) {
+  public PartSwitch1x2 duplicate(final Point position) {
-    return new PartSwitch1x2(name, x, y, state);
+    return new PartSwitch1x2(name, position, getOrientation(), state);
   }
 
 }

src/main/java/de/ph87/electro/circuit/part/impl/PartSwitchCross.java

@@ -3,6 +3,7 @@ package de.ph87.electro.circuit.part.impl;
 import de.ph87.electro.circuit.ShortCircuit;
 import de.ph87.electro.circuit.dto.PartSwitchCrossDto;
 import de.ph87.electro.circuit.part.Junction;
+import de.ph87.electro.circuit.part.Orientation;
 import de.ph87.electro.circuit.part.PartOther;
 import lombok.Getter;
 import lombok.Setter;
@@ -27,29 +28,25 @@ public class PartSwitchCross extends PartOther {
   @Setter
   private boolean state;
 
-  public PartSwitchCross(final String name, final int x, final int y, final boolean state) {
+  public PartSwitchCross(final Point position) {
-    super(name, x, y);
+    this("Kreuzschalter", position, Orientation.R0, false);
-    common0 = new Junction(this, "", JUNCTION_LEFT, FOURTH1);
+  }
-    common1 = new Junction(this, "", JUNCTION_LEFT, FOURTH3);
+
-    output0 = new Junction(this, "", JUNCTION_RIGHT, FOURTH1);
+  public PartSwitchCross(final String name, final Point position, final Orientation orientation, final boolean state) {
-    output1 = new Junction(this, "", JUNCTION_RIGHT, FOURTH3);
+    super(name, position, orientation);
-    junctions.add(common0);
+    common0 = newJunction(this, "", JUNCTION_LEFT, FOURTH1);
-    junctions.add(common1);
+    common1 = newJunction(this, "", JUNCTION_LEFT, FOURTH3);
-    junctions.add(output0);
+    output0 = newJunction(this, "", JUNCTION_RIGHT, FOURTH1);
-    junctions.add(output1);
+    output1 = newJunction(this, "", JUNCTION_RIGHT, FOURTH3);
     this.state = state;
   }
 
   public PartSwitchCross(final PartSwitchCrossDto dto) {
-    super(dto.getName(), dto.getX(), dto.getY());
+    super(dto);
-    common0 = new Junction(this, dto.getCommon0());
+    common0 = newJunction(this, dto.getCommon0(), JUNCTION_LEFT, FOURTH1);
-    common1 = new Junction(this, dto.getCommon1());
+    common1 = newJunction(this, dto.getCommon1(), JUNCTION_LEFT, FOURTH3);
-    output0 = new Junction(this, dto.getOutput0());
+    output0 = newJunction(this, dto.getOutput0(), JUNCTION_RIGHT, FOURTH1);
-    output1 = new Junction(this, dto.getOutput1());
+    output1 = newJunction(this, dto.getOutput1(), JUNCTION_RIGHT, FOURTH3);
-    junctions.add(common0);
-    junctions.add(common1);
-    junctions.add(output0);
-    junctions.add(output1);
     state = dto.isState();
   }
 
@@ -83,7 +80,7 @@ public class PartSwitchCross extends PartOther {
   }
 
   @Override
-  protected void _paint(final Graphics2D g) {
+  protected void _render(final Graphics2D g) {
     if (!state) {
       line(g, common0, output0, common0.getColor(), SWITCH_STROKE);
       line(g, common1, output1, common1.getColor(), SWITCH_STROKE);
@@ -99,8 +96,8 @@ public class PartSwitchCross extends PartOther {
   }
 
   @Override
-  public PartSwitchCross duplicate(final int x, final int y) {
+  public PartSwitchCross duplicate(final Point position) {
-    return new PartSwitchCross(name, x, y, state);
+    return new PartSwitchCross(name, position, getOrientation(), state);
   }
 
 }

src/main/java/de/ph87/electro/demo/DemoAll.java

@@ -1,21 +1,22 @@
 package de.ph87.electro.demo;
 
 import de.ph87.electro.circuit.Circuit;
+import de.ph87.electro.circuit.part.Orientation;
 import de.ph87.electro.circuit.part.impl.*;
 
+import static de.ph87.electro.CONFIG.VOLTAGE;
+
 public class DemoAll {
 
   public static Circuit create() {
-    final double voltage = 3.0;
-
     final Circuit circuit = new Circuit();
 
-    final PartBattery battery = circuit.addBattery("Batterie", 0, 0, 2, voltage);
+    final PartBattery battery = circuit.addBattery("Batterie", 0, 0, Orientation.R2, VOLTAGE);
-    final PartSwitch1x1 switcher = circuit.addSwitch1x1("Ausschalter", 2, 0, 0, false);
+    final PartSwitch1x1 switcher = circuit.addSwitch1x1("Ausschalter", 2, 0, Orientation.R0, false);
-    final PartLight light = circuit.addLight("Licht", 4, 0, 0, voltage);
+    final PartLight light = circuit.addLight("Licht", 4, 0, Orientation.R0, VOLTAGE);
-    final PartSwitch1x2 switcher0 = circuit.addSwitch1x2("Wechselschalter 0", 0, 2, 0, false);
+    final PartSwitch1x2 switcher0 = circuit.addSwitch1x2("Wechselschalter 0", 0, 2, Orientation.R0, false);
-    final PartSwitchCross switcherX = circuit.addSwitchCross("Kreuzschalter", 2, 2, 0, false);
+    final PartSwitchCross switcherX = circuit.addSwitchCross("Kreuzschalter", 2, 2, Orientation.R0, false);
-    final PartSwitch1x2 switcher1 = circuit.addSwitch1x2("Wechselschalter 1", 4, 2, 2, true);
+    final PartSwitch1x2 switcher1 = circuit.addSwitch1x2("Wechselschalter 1", 4, 2, Orientation.R2, true);
 
     circuit.connect(battery.getMinus(), switcher.getCommon());
     circuit.connect(switcher.getOutput(), light.getPin0());

src/main/java/de/ph87/electro/sidebar/Sidebar.java

@@ -1,43 +1,32 @@
 package de.ph87.electro.sidebar;
 
+import de.ph87.electro.circuit.part.Orientation;
 import de.ph87.electro.circuit.part.Part;
 import de.ph87.electro.circuit.part.impl.*;
 
 import javax.swing.*;
 import java.awt.*;
-import java.util.ArrayList;
-import java.util.List;
 import java.util.function.Consumer;
 
+import static de.ph87.electro.CONFIG.VOLTAGE;
+
 public class Sidebar extends JPanel {
 
   private final Consumer<Part> onAdd;
 
-  private final List<SidebarPart> parts = new ArrayList<>();
-
   public Sidebar(final Consumer<Part> onAdd) {
     this.onAdd = onAdd;
-    setLayout(new GridBagLayout());
+    setLayout(new FlowLayout());
-    add(new PartBattery("Batterie", 0, 0, 3.0));
+    add(new PartBattery("Batterie", new Point(0, 0), Orientation.R0, VOLTAGE));
-    add(new PartLight("Licht", 1, 0, 3.0));
+    add(new PartLight("Licht", new Point(0, 0), Orientation.R0, VOLTAGE));
-    add(new PartSwitch1x1("Ausschalter", 0, 1, false));
+    add(new PartSwitch1x1("Ausschalter", new Point(0, 0), Orientation.R0, false));
-    add(new PartSwitch1x2("Wechselschalter", 1, 1, false));
+    add(new PartSwitch1x2("Wechselschalter", new Point(0, 0), Orientation.R0, false));
-    add(new PartSwitchCross("Kreuzschalter", 0, 2, false));
+    add(new PartSwitchCross("Kreuzschalter", new Point(0, 0), Orientation.R0, false));
   }
 
   private void add(final Part part) {
     final SidebarPart entry = new SidebarPart(part, onAdd);
-    parts.add(entry);
     add(entry);
   }
 
-  @Override
-  public void paint(final Graphics g) {
-    g.setColor(Color.gray);
-    g.fillRect(0, 0, getWidth(), getHeight());
-    for (final SidebarPart part : parts) {
-      part.getPart().paint((Graphics2D) g);
-    }
-  }
-
 }

src/main/java/de/ph87/electro/sidebar/SidebarPart.java

@@ -2,15 +2,18 @@ package de.ph87.electro.sidebar;
 
 import de.ph87.electro.circuit.part.Part;
 import lombok.Getter;
+import lombok.extern.slf4j.Slf4j;
 
 import javax.swing.*;
 import java.awt.*;
-import java.awt.event.MouseAdapter;
+import java.awt.datatransfer.StringSelection;
-import java.awt.event.MouseEvent;
+import java.awt.dnd.DnDConstants;
+import java.awt.dnd.DragSource;
 import java.util.function.Consumer;
 
 import static de.ph87.electro.CONFIG.RASTER;
 
+@Slf4j
 @Getter
 public class SidebarPart extends JPanel {
 
@@ -21,15 +24,26 @@ public class SidebarPart extends JPanel {
   public SidebarPart(final Part part, final Consumer<Part> add) {
     this.part = part;
     this.add = add;
+    setTransferHandler(new TransferHandler("text"));
     setPreferredSize(new Dimension(RASTER, RASTER));
-    addMouseListener(new MouseAdapter() {
+    createDragSource(part);
+  }
 
-      @Override
+  private void createDragSource(final Part part) {
-      public void mouseClicked(final MouseEvent e) {
+    final DragSource dragSource = new DragSource();
-        add.accept(part.duplicate(e.getPoint().x / RASTER, e.getPoint().y / RASTER));
+    dragSource.createDefaultDragGestureRecognizer(
-      }
+      this,
+      DnDConstants.ACTION_COPY_OR_MOVE,
+      event -> dragSource.startDrag(event, DragSource.DefaultCopyDrop, new StringSelection(part.getClass().getSimpleName()), null)
+    );
+    part.render();
+  }
 
-    });
+  @Override
+  public void paint(final Graphics g) {
+    part.paint((Graphics2D) g);
+    g.setColor(Color.black);
+    g.drawRect(0, 0, RASTER - 1, RASTER - 1);
   }
 
 }

src/test/java/de/ph87/electro/circuit/BatteryLightTest.java

@@ -1,5 +1,6 @@
 package de.ph87.electro.circuit;
 
+import de.ph87.electro.circuit.part.Orientation;
 import de.ph87.electro.circuit.part.impl.PartBattery;
 import de.ph87.electro.circuit.part.impl.PartLight;
 import org.junit.jupiter.api.BeforeAll;
@@ -14,9 +15,9 @@ public class BatteryLightTest {
 
   private static final Circuit circuit = new Circuit();
 
-  private static final PartBattery battery = circuit.addBattery("Batterie", 1, 0, 0, VOLTAGE);
+  private static final PartBattery battery = circuit.addBattery("Batterie", 1, 0, Orientation.R0, VOLTAGE);
 
-  private static final PartLight light = circuit.addLight("Licht", 1, 1, 0, VOLTAGE);
+  private static final PartLight light = circuit.addLight("Licht", 1, 1, Orientation.R0, VOLTAGE);
 
   @BeforeAll
   public static void setUp() {

src/test/java/de/ph87/electro/circuit/BatterySwitcher1x1Test.java

@@ -1,5 +1,6 @@
 package de.ph87.electro.circuit;
 
+import de.ph87.electro.circuit.part.Orientation;
 import de.ph87.electro.circuit.part.impl.PartBattery;
 import de.ph87.electro.circuit.part.impl.PartLight;
 import de.ph87.electro.circuit.part.impl.PartSwitch1x1;
@@ -15,11 +16,11 @@ public class BatterySwitcher1x1Test {
 
   private static final Circuit circuit = new Circuit();
 
-  private static final PartBattery battery = circuit.addBattery("Batterie", 1, 0, 0, VOLTAGE);
+  private static final PartBattery battery = circuit.addBattery("Batterie", 1, 0, Orientation.R0, VOLTAGE);
 
-  private static final PartSwitch1x1 switcher = circuit.addSwitch1x1("Ein-/Ausschalter", 0, 1, 0, false);
+  private static final PartSwitch1x1 switcher = circuit.addSwitch1x1("Ein-/Ausschalter", 0, 1, Orientation.R0, false);
 
-  private static final PartLight light = circuit.addLight("Licht", 1, 1, 0, VOLTAGE);
+  private static final PartLight light = circuit.addLight("Licht", 1, 1, Orientation.R0, VOLTAGE);
 
   @BeforeAll
   public static void setUp() {

src/test/java/de/ph87/electro/circuit/BatterySwitcher1x2Test.java

@@ -1,5 +1,6 @@
 package de.ph87.electro.circuit;
 
+import de.ph87.electro.circuit.part.Orientation;
 import de.ph87.electro.circuit.part.impl.PartBattery;
 import de.ph87.electro.circuit.part.impl.PartLight;
 import de.ph87.electro.circuit.part.impl.PartSwitch1x2;
@@ -15,13 +16,13 @@ public class BatterySwitcher1x2Test {
 
   private static final Circuit circuit = new Circuit();
 
-  private static final PartBattery battery = circuit.addBattery("Batterie", 1, 0, 0, VOLTAGE);
+  private static final PartBattery battery = circuit.addBattery("Batterie", 1, 0, Orientation.R0, VOLTAGE);
 
-  private static final PartSwitch1x2 switcher = circuit.addSwitch1x2("Wechselschalter", 0, 2, 0, false);
+  private static final PartSwitch1x2 switcher = circuit.addSwitch1x2("Wechselschalter", 0, 2, Orientation.R0, false);
 
-  private static final PartLight light0 = circuit.addLight("Licht 0", 1, 1, 0, VOLTAGE);
+  private static final PartLight light0 = circuit.addLight("Licht 0", 1, 1, Orientation.R0, VOLTAGE);
 
-  private static final PartLight light1 = circuit.addLight("Licht 1", 1, 3, 0, VOLTAGE);
+  private static final PartLight light1 = circuit.addLight("Licht 1", 1, 3, Orientation.R0, VOLTAGE);
 
   @BeforeAll
   public static void setUp() {

src/test/java/de/ph87/electro/circuit/BatterySwitcher2x2Test.java

@@ -1,5 +1,6 @@
 package de.ph87.electro.circuit;
 
+import de.ph87.electro.circuit.part.Orientation;
 import de.ph87.electro.circuit.part.impl.PartBattery;
 import de.ph87.electro.circuit.part.impl.PartLight;
 import de.ph87.electro.circuit.part.impl.PartSwitch1x2;
@@ -15,13 +16,13 @@ public class BatterySwitcher2x2Test {
 
   private static final Circuit circuit = new Circuit();
 
-  private static final PartBattery battery = circuit.addBattery("Batterie", 0, 0, 0, VOLTAGE);
+  private static final PartBattery battery = circuit.addBattery("Batterie", 0, 0, Orientation.R0, VOLTAGE);
 
-  private static final PartSwitch1x2 switcher0 = circuit.addSwitch1x2("Wechselschalter 0", 0, 1, 0, false);
+  private static final PartSwitch1x2 switcher0 = circuit.addSwitch1x2("Wechselschalter 0", 0, 1, Orientation.R0, false);
 
-  private static final PartSwitch1x2 switcher1 = circuit.addSwitch1x2("Wechselschalter 1", 1, 1, 0, false);
+  private static final PartSwitch1x2 switcher1 = circuit.addSwitch1x2("Wechselschalter 1", 1, 1, Orientation.R0, false);
 
-  private static final PartLight light = circuit.addLight("Licht", 1, 0, 0, VOLTAGE);
+  private static final PartLight light = circuit.addLight("Licht", 1, 0, Orientation.R0, VOLTAGE);
 
   @BeforeAll
   public static void setUp() {

src/test/java/de/ph87/electro/circuit/BatterySwitcherCrossTest.java

@@ -1,5 +1,6 @@
 package de.ph87.electro.circuit;
 
+import de.ph87.electro.circuit.part.Orientation;
 import de.ph87.electro.circuit.part.impl.PartBattery;
 import de.ph87.electro.circuit.part.impl.PartLight;
 import de.ph87.electro.circuit.part.impl.PartSwitch1x2;
@@ -16,15 +17,15 @@ public class BatterySwitcherCrossTest {
 
   private static final Circuit circuit = new Circuit();
 
-  private static final PartBattery battery = circuit.addBattery("Batterie", 0, 0, 0, VOLTAGE);
+  private static final PartBattery battery = circuit.addBattery("Batterie", 0, 0, Orientation.R0, VOLTAGE);
 
-  private static final PartSwitch1x2 switcher0 = circuit.addSwitch1x2("Wechselschalter 0", 0, 1, 0, false);
+  private static final PartSwitch1x2 switcher0 = circuit.addSwitch1x2("Wechselschalter 0", 0, 1, Orientation.R0, false);
 
-  private static final PartSwitchCross switcherX = circuit.addSwitchCross("Kreuzschalter", 1, 1, 0, false);
+  private static final PartSwitchCross switcherX = circuit.addSwitchCross("Kreuzschalter", 1, 1, Orientation.R0, false);
 
-  private static final PartSwitch1x2 switcher1 = circuit.addSwitch1x2("Wechselschalter 1", 2, 1, 0, false);
+  private static final PartSwitch1x2 switcher1 = circuit.addSwitch1x2("Wechselschalter 1", 2, 1, Orientation.R0, false);
 
-  private static final PartLight light = circuit.addLight("Licht", 2, 0, 0, VOLTAGE);
+  private static final PartLight light = circuit.addLight("Licht", 2, 0, Orientation.R0, VOLTAGE);
 
   @BeforeAll
   public static void setUp() {

src/test/java/de/ph87/electro/circuit/CircuitServiceTest.java

@@ -1,6 +1,7 @@
 package de.ph87.electro.circuit;
 
 import de.ph87.electro.circuit.part.Junction;
+import de.ph87.electro.circuit.part.Orientation;
 import de.ph87.electro.circuit.part.Part;
 import de.ph87.electro.circuit.part.impl.PartBattery;
 import de.ph87.electro.circuit.part.impl.PartLight;
@@ -11,6 +12,7 @@ import java.io.ByteArrayOutputStream;
 import java.io.IOException;
 import java.nio.charset.StandardCharsets;
 
+import static de.ph87.electro.CONFIG.VOLTAGE;
 import static org.junit.jupiter.api.Assertions.assertEquals;
 
 class CircuitServiceTest {
@@ -18,8 +20,8 @@ class CircuitServiceTest {
   @Test
   void serialization() throws IOException {
     final Circuit circuit = new Circuit();
-    final PartBattery battery = circuit.addBattery("Batterie", 1, 0, 1, 3.0);
+    final PartBattery battery = circuit.addBattery("Batterie", 1, 0, Orientation.R1, VOLTAGE);
-    final PartLight light = circuit.addLight("Licht", 1, 1, 0, 3.0);
+    final PartLight light = circuit.addLight("Licht", 1, 1, Orientation.R0, VOLTAGE);
     circuit.connect(battery.getPlus(), light.getPin1());
     circuit.connect(light.getPin0(), battery.getMinus());
     check(circuit);
@@ -42,8 +44,7 @@ class CircuitServiceTest {
       final Part reloadedPart = reloaded.getParts().stream().filter(part -> part.getUuid().equals(originalPart.getUuid())).findFirst().orElseThrow();
       assertEquals(originalPart.getUuid(), reloadedPart.getUuid());
       assertEquals(originalPart.getName(), reloadedPart.getName());
-      assertEquals(originalPart.getX(), reloadedPart.getX());
+      assertEquals(originalPart.getPosition(), reloadedPart.getPosition());
-      assertEquals(originalPart.getY(), reloadedPart.getY());
       assertEquals(originalPart.getOrientation(), reloadedPart.getOrientation());
       assertEquals(originalPart.getJunctions().size(), reloadedPart.getJunctions().size());
       for (final Junction originalJunction : originalPart.getJunctions()) {
@@ -51,8 +52,7 @@ class CircuitServiceTest {
         final Junction reloadedJunction = reloadedPart.getJunctions().stream().filter(junction -> junction.getUuid().equals(originalJunction.getUuid())).findFirst().orElseThrow();
         assertEquals(originalJunction.getUuid(), reloadedJunction.getUuid());
         assertEquals(originalJunction.getName(), reloadedJunction.getName());
-        assertEquals(originalJunction.getX(), reloadedJunction.getX());
+        assertEquals(originalJunction.getPosition(), reloadedJunction.getPosition());
-        assertEquals(originalJunction.getY(), reloadedJunction.getY());
         assertEquals(originalJunction.getDestinations().size(), reloadedJunction.getDestinations().size());
         for (final Junction originalDestination : originalJunction.getDestinations()) {
           System.out.printf("    - Destination: %s\n", originalDestination.getUuid());