Question

我要做的是使用Java绘制一个不完整的多边形。我已经想出如何一次性绘制多边形，甚至填充多边形。我也可以使用线段绘制不完整的多边形，但问题是BasicStroke.JOIN_BEVEL不适用于线段。以下是我使用线段的方式：

//polygon is not Java's Polygon, my own implementation, and the methods do as
//they imply
for(int i = 0; i < polygon.getNumberOfPoints(); i++){
    Point2D.Double first = polygon.getPoint(i);
    Point2D.Double second = new Point2D.Double();
    if(polygon.getPoint(i+1) != null){
        second = polygon.getPoint(i+1);
        trans1 = /* some graphic translation of first */
        trans2 = /* some graphic translation of second */
        g.setColor(polygon.getColor());
        g.setStroke(new BasicStroke(polygon.getWeight(), BasicStroke.JOIN_BEVEL, BasicStroke.CAP_BUTT));
        g.draw(new Line2D.Double(trans1[0], trans1[1], trans2[0], trans2[1]));
    }
}

这很好用，但它并不能完全按照我的意愿行事。 g.setStroke(/*stuff here*/);对关节没有影响。

Answer 1

嗯，我完全错过了一种方法。

g.drawPolyline(int[] xCoords, int[] yCoords, int numPoints)

这解决了我的问题。

Answer 2

创建Path2D.Double，但不要调用closePath（）。

Path2D.Double path = new Path2D.Double();
for (int i = 0; i < polygon.getNumberOfPoints(); i++) {
  Point2D.Double point = polygon.getPoint(i);
  trans1 = /* some graphic translation */;
  if (i == 0)
    path.moveTo(trans1[0], trans1[1]);
  else
    path.lineTo(trans1[0], trans2[0]);
}
g.setColor(polygon.getColor());
g.setStroke(new BasicStroke(polygon.getWeight(), BasicStroke.JOIN_BEVEL, BasicStroke.CAP_BUTT));
g.draw(path);

如何使用Java绘制不完整的Polygon

2 个答案: