Make surface contour levels configurable

[etpinard]

... with autocontours, ncontours, contour.start, contour.end and contour.size.

Looks like gl-surface3d already has that feature; it would just a matter of exposing the contour calc step so that the surface convert step can reuse it to fill the contourLevels gl-surface3d property.

[alexcjohnson]

Also for x/y contours it would be nice to just say "all data points" ie display a dense wireframe of the data, whether it's uniform or not (eg #2713). Not sure if there's a use case for it, but in principle you could also imagine wanting to specify each individual contour level ala tickvals on an axis (which do currently map into nonuniform contour levels, see https://codepen.io/alexcjohnson/pen/gKLBgR?editors=0010)

[Koushikphy]

This is a nice way to plot wireframe plot using plotly.js by providing hidesurface:true. But the only problem is I can't make the last/end line visible even though I'm giving all the tickvals. Anyway to show that last line?

[archmoj]

@Koushikphy Thanks for reporting this.
@etpinard I don't know if this was mentioned before? If so we may open a new issue and I would try to address that in the PR related to gl-surface3d module.
Here is a demo in respect to that.

[yaozhewei]

Has there been any updates? This would be a very good feature to have

[etpinard]

@archmoj wanna close this thing?

[archmoj]

Hmm...
The surface contours are quite configurable.
So yes let's close this for now.

[Koushikphy]

I still can't get the last contour line. If my data is upto say xMax then providing end:xMax doesn't draw the contour line corresponding contour line.