display coordinates

Display coordinates are the natural coordinates of display screens.

The display coordinates of the upper-left corner of every display is fixed at
(xDisp,yDisp) = (0,0) .

Display coordinates (xDisp,yDisp) increase by 1 unit per pixel rightward and downward, and
cannot be offset, inverted or scaled.

window coordinates

Window coordinates are the natural coordinates of windows.

The window coordinates of the upper-left corner of every window is fixed at (xWin,yWin) =
(0,0) .

Window coordinates (xWin,yWin) increase by 1 unit per pixel rightward and downward and
cannot be offset, inverted or scaled.

local coordinates

Local coordinates are the natural coordinates of grids.

The local coordinates of the upper-left corner of every grid is fixed at (x,y) = (0,0) .

Local coordinates (x,y) increase by 1 unit per pixel rightward and downward and cannot be
offset, inverted or scaled.