package cs3500.turtle.view; import java.awt.*; import java.awt.geom.AffineTransform; import java.util.ArrayList; import java.util.List; import javax.swing.*; import cs3500.turtle.model.Position2D; import cs3500.turtle.tracingmodel.Line; /** * This panel represents the region where the * lines of the turtle must be drawn. *

* If one has to create a container that makes * custom drawing, the conventional way is to * create a class that extends JPanel or JLabel */ public class TurtlePanel extends JPanel { private List lines; private Position2D turtlePosition; private double turtleHeading; //the rectangle within which all lines lie private Position2D minD, maxD; public TurtlePanel() { super(); lines = new ArrayList(); this.setBackground(Color.WHITE); minD = new Position2D(0, 0); maxD = new Position2D(0, 0); turtlePosition = new Position2D(0, 0); turtleHeading = 0.0; } public void setTurtlePosition(Position2D pos) { turtlePosition = new Position2D(pos); } public void setTurtleHeading(double h) { turtleHeading = h; } public void setLines(List lines) { this.lines = new ArrayList(lines); List points = new ArrayList(); for (Line l : this.lines) { points.add(new Position2D(l.start)); points.add(new Position2D(l.end)); } if (points.size() > 0) { minD = points.get(0); maxD = points.get(1); for (Position2D p : points) { if (p.getX() < minD.getX()) { minD = new Position2D(p.getX(), minD.getY()); } if (p.getY() > minD.getY()) { minD = new Position2D(minD.getX(), p.getY()); } } for (Position2D p : points) { if (p.getX() > maxD.getX()) { maxD = new Position2D(p.getX(), maxD.getY()); } if (p.getY() > maxD.getY()) { maxD = new Position2D(maxD.getX(), p.getY()); } } } } /** * Override the paintComponent method of the JPanel * Do NOT override paint! * * @param g */ @Override protected void paintComponent(Graphics g) { //never forget to call super.paintComponent! super.paintComponent(g); Graphics2D g2d = (Graphics2D) g; g2d.setColor(Color.BLACK); /* the origin of the panel is top left. In order to make the origin bottom left, we must "flip" the y coordinates so that y = height - y We do that by using an affine transform. The flip can be specified as scaling y by -1 and then translating by height. */ AffineTransform originalTransform = g2d.getTransform(); //the order of transforms is bottom-to-top //so as a result of the two lines below, //each y will first be scaled, and then translated g2d.translate(0, this.getPreferredSize().getHeight()); g2d.scale(1, -1); for (Line l : lines) { Position2D start = l.start; Position2D end = l.end; g2d.drawLine((int) start.getX(), (int) start.getY(), (int) end.getX(), (int) end.getY()); } //draw the turtle //an easy way to draw the turtle would be //to draw it in its default position, and then //rotate it by heading and translating it to //its actual position g2d.translate(Math.round(turtlePosition.getX()), Math.round( turtlePosition.getY ())); g2d.rotate(Math.toRadians(turtleHeading)); g2d.setColor(Color.BLUE); g2d.fillOval(-2, -2, 4, 4); g2d.setColor(Color.BLACK); g2d.fillOval(-1, -1, 2, 2); g2d.setColor(Color.RED); g2d.fillOval(-8, -4, 8, 8); //reset the transform to what it was! g2d.setTransform(originalTransform); } }