Thus the coordinate pair (100, 75) indicates a position on the screen that is 100 pixels inward from the left edge of the window and 75 pixels down from the top.
It retrieves the dimensions of the desktop and the window then calculates the appropriate coordinate of the left upper corner of the window to make it center.
它重新获取桌面和窗口的尺寸规格，然后计算窗口左上角合适的坐标来使它位于屏幕中心。
3
Hexagonal grid coordinate and the relation of the circle window and the line to be clipped are demonstrated.