我希望在Java Swing中画一个三角形,其顶点略微平滑。我学会了使用以下代码绘制三角形:
Polygon p=new Polygon (vertice_x, vertices_y, number_of_vertices);
g.drawPolygon(p);
但我没有找到关于圆角的内容。我读到Graphics2D中有一种方法可以绘制带有圆角边框的矩形,但对于一般的多边形呢?我该怎么做呢?
我希望在Java Swing中画一个三角形,其顶点略微平滑。我学会了使用以下代码绘制三角形:
Polygon p=new Polygon (vertice_x, vertices_y, number_of_vertices);
g.drawPolygon(p);
但我没有找到关于圆角的内容。我读到Graphics2D中有一种方法可以绘制带有圆角边框的矩形,但对于一般的多边形呢?我该怎么做呢?
如果需要更精细地控制圆角(而不仅仅使用Stroke),可以将3条线组合在一起用于边,以及3条Bezier曲线用于圆角。使用线性插值获取线和曲线的起点/终点,并以角点为曲线的控制点。
public Point interpolate(Point p1, Point p2, double t){
return new Point((int)Math.round(p1.x * (1-t) + p2.x*t),
(int)Math.round(p1.y * (1-t) + p2.y*t));
}
Point p1 = new Point(50,10);
Point p2 = new Point(10,100);
Point p3 = new Point(100,100);
Point p1p2a = interpolate(p1, p2, 0.2);
Point p1p2b = interpolate(p1, p2, 0.8);
Point p2p3a = interpolate(p2, p3, 0.2);
Point p2p3b = interpolate(p2, p3, 0.8);
Point p3p1a = interpolate(p3, p1, 0.2);
Point p3p1b = interpolate(p3, p1, 0.8);
...
g.drawLine(p1p2a.x, p1p2a.y, p1p2b.x, p1p2b.y);
g.drawLine(p2p3a.x, p2p3a.y, p2p3b.x, p2p3b.y);
g.drawLine(p3p1a.x, p3p1a.y, p3p1b.x, p3p1b.y);
QuadCurve2D c1 = new QuadCurve2D.Double(p1p2b.x, p1p2b.y, p2.x, p2.y, p2p3a.x, p2p3a.y);
QuadCurve2D c2 = new QuadCurve2D.Double(p2p3b.x, p2p3b.y, p3.x, p3.y, p3p1a.x, p3p1a.y);
QuadCurve2D c3 = new QuadCurve2D.Double(p3p1b.x, p3p1b.y, p1.x, p1.y, p1p2a.x, p1p2a.y);
g.draw(c1);
g.draw(c2);
g.draw(c3);
interpolate
的t
参数以更改圆角的弯曲程度。Path2D
实现了Shape
接口,其中包括将对象传递给Graphics2D.fill
以填充形状的功能。Path2D path = new Path2D.Double();
AffineTransform at = new AffineTransform();
path.moveTo(p1p2a.x, p1p2a.y);
path.lineTo(p1p2b.x, p1p2b.y);
path.append(c1.getPathIterator(at), true);
path.lineTo(p2p3b.x, p2p3b.y);
path.append(c2.getPathIterator(at), true);
path.lineTo(p3p1b.x, p3p1b.y);
path.append(c3.getPathIterator(at), true);
path.closePath();
g.fill(path);
Graphics
的颜色来改变颜色,例如g.setColor(Color.RED)
。 - copegdrawRoundPolygon(int vertices, int arc)
之类的方法,但实际上并没有,而且要做起来也不那么简单和直观。非常感谢你提供这个! - akmswprotected Path createShapePath() {
Path path = new Path();
float cornerRadius = 10.0f; // Adjust the radius to control the roundness of the corners
// Starting point at the bottom-left corner
path.moveTo(shapeBox.left , shapeBox.bottom - cornerRadius );
// Top point with rounded edge
path.lineTo(shapeBox.centerX() - cornerRadius, shapeBox.top + cornerRadius);
path.arcTo(new RectF(shapeBox.centerX() - cornerRadius, shapeBox.top, shapeBox.centerX() + cornerRadius, shapeBox.top + 2 * cornerRadius), 180, 180);
// Bottom-right point with rounded edge
path.lineTo(shapeBox.right, shapeBox.bottom - cornerRadius);
path.arcTo(new RectF(shapeBox.right- 2 * cornerRadius , shapeBox.bottom - 2 * cornerRadius, shapeBox.right, shapeBox.bottom), 0, 90);
// Bottom-left point with rounded edge
path.lineTo(shapeBox.left + cornerRadius , shapeBox.bottom );
path.arcTo(new RectF(shapeBox.left, shapeBox.bottom - 2 * cornerRadius, shapeBox.left + 2 * cornerRadius, shapeBox.bottom), 90, 90);
// Close the path
path.close();
return path;
}
JOIN_ROUND
。当然,这只是最基本的,你还可以使用scale
。 - Joop Eggen