[XForms] Pixmap buttons

[jon]

I am not an expert on C or X11 so frankly this is giving me a headache.

What I need is some form of 24 bit image I can both click on and modify
the contents. Just a block of plain colour would do.

I've spent two days playing with code around pixmaps and frankly I am
loosing the will to live.

Does anyone know of a simple way to create a clickable 24 bit image
(with a callback) where the image can be modified by the callback.

I need a block of colour, I click to select a colour picker, pick a new
colour, then that block of colour needs to be the newly selected RGB
colour. I do not want to use colour maps as I may need a large number
of these controls.


At the moment I have tried including pixmap .h files, copying the data
into malloced RAM, setting the object u_cdata to the malloced pointer
then trying to code something to modify the pixmap data.  My skill
level is not up to the job as I've spent the entire time fighting the C
compiler and failing.

https://www.youtube.com/watch?v=taHynxvTlwo&feature=youtu.be

I want they grey part of the "RGB Test" pixmap to be the newly selected
colour.


Any help gratefully received.

Thanks,
Jon