code: private void drawPoint(BufferedImage image) {
          if (this.pointPower == -1) {
              return;
          }
          Random r = new Random();
          Graphics2D g2 = (Graphics2D) image.getGraphics();
          int max = this.w * this.h / this.pointPower;
          for (int i = 0; i < max; i++) {
              int x = r.nextInt(w);
              int y = r.nextInt(h);
              g2.setStroke(new BasicStroke(1.5F));
              g2.setColor(this.randomColor());
              g2.drawOval(x, y, 1, 1);
          }
          g2.dispose();
      }
docs: 随机画点
  
  @param image 图片