[WIP] Add bounds and boundmode

[MrQubo]

Adds bounds and boundmode axis attributes as suggested in plotly#1876.

Replaced boundmode with boundon. Replaced 'soft' and 'hard' with 'autorange' and 'interaction'.

Based on https://github.com/g-i-o-/plotly.js/pull/1.

[mbkupfer]

@MrQubo, this has been referenced in an issue (plotly#1876) which I have been watching and eagerly awaiting. That said, it still sounds abstract compared to the underlying feature request. Could you clarify if this solves the interactive axis scaling?

Also, I use plotly.py. will this be ported to that as well?

Thanks!

[MrQubo]

@mbkupfer
It's Work in Progress, not yet fully working.

I'm not sure what do you mean by "interactive axis scaling". Here I'm trying to implement only part of plotly#1876 which is bounds and boundmode attributes.

Regarding porting to plotly.py, I'm not planning to. I think that plotly.py uses plotly.js under the hood so there's no need to do much except for adding new attributes.

[MrQubo]

Tested manually for normal, log, category and reversed axes with multiple traces (scatter and bar) and one plot (no subplots).

[MrQubo]

Currently, when two axes are constrained then only bounds on the one being dragged will be respected.

[mbkupfer]

I'm not sure what do you mean by "interactive axis scaling".

I was referring to making a range selection along the x axis and the y-axis rescaling. An important use case for this are long time-series plots which have had volatile periods.

There are some workarounds, but they all require hacky javascript and don't work for all types of axis.

[mbkupfer]

Here is a community post that most accurately explains the "interactive axis scalling"

https://community.plot.ly/t/autorescaling-y-axis-range-when-range-slider-used/12214/4

[MrQubo]

@mbkupfer
I see now. Sorry, but this is a different feature. plotly#1876 is a combo of multiple features and I referenced it because here I'm trying to implement one of those features.

[mbkupfer]

Got it. Well thanks anyways for the contribution to this issue. I wish I knew JS well enough to contribute as well.