coordinate system in C#

1. Types of Coordinate Systems

GDI+ uses three coordinate spaces: world, page, and device. World coordinates are the coordinates used to model a particular graphic world and are the coordinates you pass to methods in the .NET Framework. Page coordinates refer to the coordinate system used by a drawing surface, such as a form or control. Device coordinates are the coordinates used by the physical device being drawn on, such as a screen or sheet of paper. When you make the call myGraphics.DrawLine(myPen, 0, 0, 160, 80), the points that you pass to the DrawLine method—(0, 0) and (160, 80)—are in the world coordinate space. Before GDI+ can draw the line on the screen, the coordinates pass through a sequence of transformations. One transformation, called the world transformation, converts world coordinates to page coordinates, and another transformation, called the page transformation, converts page coordinates to device coordinates.