perlin-bug.java

    public static final int WIDTH = 128;
    public static final int HEIGHT = WIDTH;
    public static final double PERIOD = 1000;

    public static void main(String[] args) throws IOException {
        Perlin perlin = new Perlin();
        Path path = Paths.get("perlin.png");
        BufferedImage image = new BufferedImage(WIDTH, HEIGHT, BufferedImage.TYPE_INT_ARGB);
        Graphics2D graphics = image.createGraphics();

        perlin.setNoiseQuality(NoiseQuality.BEST);

        for (int y = 0; y < HEIGHT; y++) {
            for (int x = 0; x < WIDTH; x++) {
                double value = perlin.getValue(x * PERIOD, y * PERIOD, 0);

                graphics.setColor(Color.getHSBColor(0, 0, (float) value));
                graphics.fillRect(x, y, 1, 1);
            }
        }

        ImageIO.write(image, "PNG", path.toFile());
    }