Make displaz remember settings between runs

[c42f]

Request from Andrew Barker:

Would it be possible to make displaz retain the last used shader parameters?

I would like to be able to set a default background colour, colour mode and point radius.

[c42f]

Having a persistent displaz window (using socket IPC at startup) might be even better for some use cases.

[nigels-com]

Qt has some infrastructure for this kind of thing (as I recall) at startup and shutdown. From a user experience point of view, returned to something "as I left it" it productive, especially for a viewer.

[c42f]

Yes, definitely use QSettings here. It's a simple matter of connecting it up to things as necessary. Getting it to work smoothly with the dynamic and user-configurable shader parameter GUI may be interesting.