docs: public String getSVGString(int width){
          StringBuffer out = new StringBuffer();
  
          int x = (int)(point.value(x_dim)*window_size);
          int y = (int)(point.value(y_dim)*window_size);
          int radius = panel_size/2;
          //radius = 1;
  
          Color c = getColor();
  
          String color = "rgb("+c.getRed()+","+c.getGreen()+","+c.getBlue()+")";
          double trans = c.getAlpha()/255.0;
  
          out.append("<circle ");
          out.append("cx='"+x+"' cy='"+y+"' r='"+radius+"'");
          out.append(" stroke='"+color+"' stroke-width='0' fill='"+color+"' fill-opacity='"+trans+"' stroke-opacity='"+trans+"'/>");
          out.append("\n");
          return out.toString();
      }