6.4: Calibrating a touchpanel with 4 point algorithm

I have a driver (for a penmount device) that doesn’t understand the 3 point calibration file, so I need to use the 4 point algorithm.

But there is a problem: the calib tool doesn’t show the bullseyes on the complete screen.

Little sketch to show what I mean:


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As a consequence when I touch the bullseyes as shown above, I can’t use the whole touchschreen after calibration.
When I ignore the bullseyes and touch the 4 corners of the screen, everything is fine.

The problem is: How shall I tell the customer that he mustn’t touch the bullseyes but the corners of his screen? :slight_smile:

I have tried several options like offset, manual setting of the screenwidth via -d, but it doesn’t take effect.

Has anyone had this problem too?


Edit: I have created a little picture to show my problem.

Is this using Photon or AG?

I think the issue is more a driver bug or configuration issue than a calib issue.

Calib queries the driver to figure out the screen pixel size and then places the corner images accordingly. It appears that this doesn’t line up with your actual screen which makes me think something isn’t configured correctly with your driver.

It is photon.

I don’t think that this is a problem of the driver.
I have used two different Touchpanels: Microtouch and Penmount.
With both Panels this issue occurs when I use the 3 point calibration method.

With both panels the calib tool doesn’t place the bullseyes into the 4 corners.