>hello
>thank you for your replay,but where exactly i can find that xy system

I was referring to the traditional Cartesian coordinate system: X is to the right, -X is to the left, Y is up, -Y is down.

However, in Visual FoxPro the coordinates start from the top-left corner of a form; X is to the right, Y is down, and negative coordinates are outside the visible form (beyond the top, or to the left).

Here is an example, to draw a circle; I put it on a Command.Click():

ThisForm.Circle(20, 100, 70)

This means: Draw a circle of radius = 20. The center of the circle is 100 pixels to the right of the left border; and 70 pixels below the top border.

The main conversion you have to do is with the "Y" coordinate, because positive values go down instead of up; if you have a number "Y" that should go UP instead of DOWN, find a reasonable maximum, for example 500 pixels, and place the center of the circle at 500-Y.