draw2d根据两点位置画圆弧

妖狐艹你老母 2023-10-13 10:32 19阅读 0赞

可以说圆的中心是(x0，y0)，圆弧包含您的两个点(x1，y1)和(x2，y2)。 然后半径为：r = sqrt((x1-x0)(x1-x0)+(y1-y0)(y1-y0))。

## 一、已知两点画圆弧 ##

public void drawArc(Point p1,Point p2,Object object) {
    		int xCenter = p1.x;
    		if(p1.x > p2.x)
    			xCenter = p2.x + ((p1.x-p2.x)/2);
    		else if(p1.x < p2.x)
    			xCenter = p1.x + ((p2.x-p1.x)/2);
    		
    		int yCenter= p1.y;
    		if(p1.y > p2.y)
    		        yCenter = p1.y - ((p1.y-p2.y)/2);
    		else if(p1.y < p2.y)
    		        yCenter = p2.y - ((p2.y-p1.y)/2);
    		int diameter =(int) Math.sqrt(Math.pow((p1.x-p2.x),2)+Math.pow((p1.y-p2.y),2));
    		int r = diameter/2;
    		int x = xCenter-r;
    		int y = yCenter-r;
    		int width = 2*r;
    		int heigh= 2*r;
    		int startAngle = (int) ((180/Math.PI)*Math.atan2(p1.y-yCenter, p1.x-xCenter));
    		int endAngle = (int) ((180/Math.PI)*Math.atan2(p2.y-yCenter, p2.x-xCenter));
    		int arcLength = endAngle-startAngle;
    		if (object instanceof Path) {
    			((Path) object).addArc(x, y, width, heigh, startAngle, arcLength );
    		}else if (object instanceof Graphics) {
    			((Graphics) object).fillArc(x, y, width, heigh, startAngle, arcLength);
    		}
    	}

## 二、已知两端点和圆点画圆弧 ##

public void drawArc(Point p1,Point p2,Object object，int xCenter,int yCenter) {
    
    		int diameter =(int) Math.sqrt(Math.pow((p1.x-p2.x),2)+Math.pow((p1.y-p2.y),2));
    		int r = diameter/2;
    		int x = xCenter-r;
    		int y = yCenter-r;
    		int width = 2*r;
    		int heigh= 2*r;
    		int startAngle = (int) ((180/Math.PI)*Math.atan2(p1.y-yCenter, p1.x-xCenter));
    		int endAngle = (int) ((180/Math.PI)*Math.atan2(p2.y-yCenter, p2.x-xCenter));
    		((Graphics) object).fillArc(x, y, width, heigh, startAngle, endAngle);
    		
    	}