Matrix.mapRect()理解

RectF r = new RectF(50, 0, 100, 100);
Log.d("m1", "-r.left = " + r.left + ", right = " + r.right + ", top = "
		+ r.top + ", bottom = " + r.bottom);
Matrix m = new Matrix();
m.setScale(2, 3);

m.mapRect(r);
Log.d("m1", "-r.left = " + r.left + ", right = " + r.right + ", top = "
		+ r.top + ", bottom = " + r.bottom);		

 

上面这段代码log如下:

D/m1      (20694): -r.left = 50.0, right = 100.0, top = 0.0, bottom = 100.0
D/m1      (20694): -r.left = 100.0, right = 200.0, top = 0.0, bottom = 300.0

 

所以mapRect是单独对RectF的坐标点进行矩阵变换。

posted on 2015-08-12 15:58  Matrixin  阅读(3110)  评论(0编辑  收藏  举报

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