Display a block in each of the four corners of the display, and ask the user to press on them.
The X and Y values for each corner will provide the basis for your calibration.
You may find just two points on a diagonal are sufficient.
Display a block in each of the four corners of the display, and ask the user to press on them.
The X and Y values for each corner will provide the basis for your calibration.
You may find just two points on a diagonal are sufficient.