Automated Colour Picker

[Fred]

In the past OLV chose colours purely randomly, mostly that worked out OK, but it's possible to do much better. I asked Ben to have a crack, and this is the result:



The file name is appropriately called GreenAndPurpleOLV :-) I'm not sure that it's better than before, but it's certainly not worse and we now have a good interface in there.

This thread is to discuss algorithms for choosing unique colours, especially in a single division box.

And I noticed a bug:



The bottom scroll bar hides the last bit if the window is too small vertically.

No time to discuss further now, but I'm sure we can improve upon what Ben has so kindly started!

I'll push those changes to my repo and Gufi's tomorrow. Adios.

Fred.

[BenFenner]

I wrote it as if there might be 1,024 possible colors needed (logged data streams) all showing and needing color at one time. If we want to narrow that down it would be easier and could get as simple as brute coding good color defaults.
Also, I admit it could be much better regardless. The problem I ran into was the spot I had to "hook" into to apply the color was less than ideal. And after almost two days of trying to fight that, I decided results sooner would be better than nothing later.

Scroll bar bug is probably from me trying to get the window sized properly on my machine, and not testing it on other configurations. That will be a simple revert, as that was my first commit and completely separate from the second commit with the color changes.

[BenFenner]

algorithms for choosing unique colours, especially in a single division box.

Here's the problem... It will take quite an effort I think to get the program to not assign colors until they are absolutely needed, and to again relinquish the colors once they are no longer absolutely needed (not displayed). If that were in place, the problem would be trivial. As it stands, colors are assigned early, never relinquished, and obviously are not "division box aware".

As for algorithm, I won't get into mine since it is the fourth iteration and it's still kinda crap. It can be done better. I think simply changing hue is not enough either. It should also be altering lightness.

[BenFenner]

I'm really thinking just a "brute force" list of high contrasting colors might be in order as a hold-over until the GUI and code can get a much needed overhaul (making user selectable line colors extremely simple)?

As it stands, I'm gunna get some stuff done at work and we can revisit this in a couple days, or decide to dive into other stuff like getting graph gradations, axis labels, your dynamic scaling, etc., etc.

[Fred]

Your call, and yes, brute force may be the best approach, and I wondered if you were facing some limitations there.

It clearly selects the colour when you "pick up" a field. Much better to select when you drop the field. Maybe I can have a look? Not today, though.

Fred.

[BenFenner]

It might look like it chooses the color when you pick it up, but it's chosen from the get-go when you load the log.
I'm feeling much more confident coding this program now. Any time we want to revisit this it shouldn't take but a moment.
As is, there are lower hanging fruit I feel.

[Fred]

Sweet, your call! It doesn't do the all grey thing very often anyway :-)

[Fred]

However, it does need to be chosen when you drop it, not at load, or pick up, because that's the only time you know where it's going and what the surrounding and existing colours are. It also needs to take into account saved settngs and use those first if available :-)

[BenFenner]

Absolutely. I think these changes will probably go hand-in-hand with the next scheduled major UI overhaul. Better color behavior might wait until then.

Further conversation can go in my development diary instead since that's up now.

[Fred]

Sure, sounds reasonable, it's no show stopper anyway. Probably my most common usage mode is 5 or 6 or 7 or 8 boxes with one value in them each. So merely looking at position gives you the info you need. It might be better to have all those values in one division with distinct colours at full scale, though. I don't know. I look forward to using it when I can add 20 to full scale with unique colours, or 10 to one and make it 3/4 of the height and put 2 in the final 1/4 :-) etc.