Understanding Coordinate Systems
Several different coordinate systems are supported by the Intel® Fortran QuickWin Library.
Text coordinates use a coordinate system that divides the screen into rows and columns.
Graphics coordinates are specified using one of three coordinate systems:
Physical coordinates, which are determined by the hardware and the video mode used
Viewport coordinates, which you can define in the application
Window coordinates, which you can define to simplify scaling of floating-point data values
Physical coordinates serve as an absolute reference and as a starting place for creating custom window and viewport coordinates. Conversion routines make it simple to convert between different coordinate systems.
Unless you change it, the viewport-coordinate system is identical to the physical-coordinate system. The physical origin (0, 0) is always in the upper-left corner of the display.
For QuickWin, display means a child window's client area, not the actual monitor screen (unless you go to Full Screen mode). The x-axis extends in the positive direction left to right, while the y-axis extends in the positive direction top to bottom. The default viewport has the dimensions of the selected mode. In a QuickWin application, you can draw outside of the child window's current client area. If you then make the child window bigger, you will see what was previously outside the frame.
You can also use coordinate routines to convert between physical-, viewport-, and window-coordinate systems.