hand drawing effect with JavaFX

gistfile1.java

package com.guigarage.incubator.wobble;

import javafx.application.Application;
import javafx.geometry.Point2D;
import javafx.scene.Group;
import javafx.scene.Scene;
import javafx.scene.paint.Color;
import javafx.scene.shape.*;
import javafx.stage.Stage;

public class WobbleTest extends Application {

    public static void main(String... args) {
        launch(args);
    }

    @Override
    public void start(Stage primaryStage) throws Exception {

        Group group = new Group();
        group.getChildren().add(createHandDrawnRect(10, 10, 100, 100, 2, Color.BLACK));
        group.getChildren().add(createHandDrawnRect(100, 150, 450, 40, 2, Color.BLACK));
        group.getChildren().add(createHandDrawnRect(150, 10, 100, 100, 2, Color.BLACK));

        group.getChildren().add(createHandDrawnArrow(100, 100, 160, 160, 2, Color.BLACK));


        primaryStage.setScene(new Scene(group));
        primaryStage.show();
    }

    public Shape createHandDrawnRect(double x1, double y1, double w, double h, double strokeWidth, Color color) {
        Shape top = createHandDrawnLine(x1, y1, x1 + w, y1, strokeWidth, color);
        Shape bottom = createHandDrawnLine(x1, y1 + h, x1 + w, y1 + h, strokeWidth, color);
        Shape left = createHandDrawnLine(x1, y1, x1, y1 + h, strokeWidth, color);
        Shape right = createHandDrawnLine(x1 + w, y1, x1 + w, y1 + h, strokeWidth, color);
        return Shape.union(top, Shape.union(bottom, Shape.union(left, right)));
    }

    public Shape createHandDrawnArrow(double x1, double y1, double x2, double y2, double strokeWidth, Color color) {
        Shape line = createHandDrawnLine(x1, y1, x2, y2, strokeWidth, color);

        double arrowlenght = strokeWidth * 5;
        double distance = Math.sqrt(Math.pow(x2 -x1, 2) + Math.pow(y2 -y1, 2));
        double unrotatedX = x2 + ((x1 - x2) / distance) * arrowlenght;
        double unrotatedY = y2 + ((y1 - y2) / distance) * arrowlenght;

        Point2D rotated1 = new Point2D(x2 + (unrotatedX - x2)*Math.cos(0.5) - (unrotatedY - y2)*Math.sin(0.5), y2 + (unrotatedX - x2)*Math.sin(0.5) + (unrotatedY - y2)*Math.cos(0.5));
        Shape arrowLeft = createHandDrawnLine(x2, y2, rotated1.getX(), rotated1.getY(), strokeWidth, color);

        Point2D rotated2 = new Point2D(x2 + (unrotatedX - x2)*Math.cos(-0.5) - (unrotatedY - y2)*Math.sin(-0.5), y2 + (unrotatedX - x2)*Math.sin(-0.5) + (unrotatedY - y2)*Math.cos(-0.5));
        Shape arrowRight = createHandDrawnLine(x2, y2, rotated2.getX(), rotated2.getY(), strokeWidth, color);
        return Shape.union(line, Shape.union(arrowLeft, arrowRight));
    }

    public Shape createHandDrawnLine(double x1, double y1, double x2, double y2, double strokeWidth, Color color) {
        Point2D startPoint = new Point2D(x1, y1);
        Point2D endPoint = new Point2D(x2, y2);

        double wobble = Math.sqrt((endPoint.getX() - startPoint.getX()) * (endPoint.getX() - startPoint.getX()) + (endPoint.getY() - startPoint.getY()) * (endPoint.getY() - startPoint.getY())) / 25;

        double r1 = Math.random();
        double r2 = Math.random();

        double xfactor = Math.random() > 0.5 ? wobble : -wobble;
        double yfactor = Math.random() > 0.5 ? wobble : -wobble;

        Point2D control1 = new Point2D((endPoint.getX() - startPoint.getX()) * r1 + startPoint.getX() + xfactor, (endPoint.getY() - startPoint.getY()) * r1 + startPoint.getY() + yfactor);
        Point2D control2 = new Point2D((endPoint.getX() - startPoint.getX()) * r2 + startPoint.getX() - xfactor, (endPoint.getY() - startPoint.getY()) * r2 + startPoint.getY() - yfactor);

        MoveTo startMove = new MoveTo(startPoint.getX(), startPoint.getY());
        CubicCurveTo curve = new CubicCurveTo(control1.getX(), control1.getY(),
                control2.getX(), control2.getY(),
                endPoint.getX(), endPoint.getY());

        Path path = new Path(startMove, curve);
        path.setStrokeLineCap(StrokeLineCap.ROUND);
        path.setStroke(color);
        path.setStrokeWidth(strokeWidth + (strokeWidth * (Math.random() - 0.5) / 8.0));
        path.setStrokeType(StrokeType.CENTERED);
        return path;
    }
}