Add support for modifying the opacity and area color

[jacomago]

Adds two new columns to the traces:

• AreaOpacity Which sets the opacity for the area, keeping the color from the trace
• AreaColor Which is by default the trace color with the opacity from the AreaOpacity

This allows the user when looking at more spiky data to easily see the min, max peaks. Right now mostly they resort to swapping to raw data.

Checklist

• Testing:
  • The feature has automated tests
  • Tests were run
  • If not, explain how you tested your changes
    Opened the data browser and tested a few traces.
• Documentation:
  • The feature is documented
  • The documentation is up to date
  • Release notes:
    • Added an entry if the change is breaking or significant
    • Added an entry when adding a new feature

[sonarqubecloud]

Quality Gate passed

Issues
21 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud

[kasemir]

Do we really need two new options for each trace??
Wouldn't just one global "opacity" suffice? For example, in the "Misc." tab below Foreground and Background color, add "Area Opacity:" with 0-100%.

[jacomago]

Do we really need two new options for each trace?? Wouldn't just one global "opacity" suffice? For example, in the "Misc." tab below Foreground and Background color, add "Area Opacity:" with 0-100%.

Yes maybe, I'll play around with some different options.

[jacomago]

fixes #3723

[georgweiss]

@kasemir, what is your take on globally configurable area color? Changing opacity to 100% will make the statistics-related data indistinguishable.

[kasemir]

I'm for keeping it simple. One color per trace. The area uses a lighter/transparent variant of the trace's color.

The original issue was that different people have different preferences for the lightness or transparency. So make that one new configuration parameter. For example, in the "Misc." tab below Foreground and Background color, add "Area Opacity:" with 0-100%.

For both the end user and the maintainer of the source code, adding a new AreaColor plus AreaOpacity per trace seems complete overkill. But I think I stated that above, so do whatever.