Where does GIMP get graphics tablet input data?

Paralel · 02-07-2009, 08:34 AM

I'm thinking of writing an add-on for GIMP that would provide more control over the data received from a graphics tablet. Now, I'm not sure how GIMP receives said input data - can this add-on be made as a simple plugin or would I have to get dirty with the core?

Also, what would be the best place to find more info about how GIMP works?

Thanks!

jschiwal · 02-07-2009, 08:38 AM

Gimp get the signals from the xorg server not from the pad. Start looking there and the kernel driver first.

Paralel · 02-07-2009, 10:37 AM

Quote:

Originally Posted by jschiwal

Gimp get the signals from the xorg server not from the pad. Start looking there and the kernel driver first.

So it wouldn't be possible to just change the way GIMP interprets the data, I'd have to start from the kernel driver?

jschiwal · 02-07-2009, 10:46 AM

Depends. Are there signals ignored by gimp? Or should some things like gestures be handled by the gimp.

What do you want to add or handle differently. If there is a button that is dead, that is probably an xorg.conf configuration issue. If you want a line to thicken if there is more pressure applied, and the driver does provide pressure information, that might be something you can add.

Paralel · 02-07-2009, 11:09 AM

Quote:

Originally Posted by jschiwal

Depends. Are there signals ignored by gimp? Or should some things like gestures be handled by the gimp.

What do you want to add or handle differently. If there is a button that is dead, that is probably an xorg.conf configuration issue. If you want a line to thicken if there is more pressure applied, and the driver does provide pressure information, that might be something you can add.

I was thinking along the lines of a mass effect from Inkscape and/or to make it easier to draw straight lines - perhaps ignoring some of the input data sent so as to avoid "wobbly" lines.

So yes, just reinterprenting data that is already received by GIMP in different ways.