Mesh3d: false information displayed on hover when hovertemplate gives cell intensities or facecolor

[empet]

When intensitymode='cell' and the hovertemplate is defined like this:

hovertemplate = "cell intensity": %{intensity: .3f}"

or if I define as customdata the array of face center coordinates
and a hovertemplate of the form:

hovertemplate ="fx: %{customdata[0]:.3f}<br>fy: %{customdata[1]:.3f}"+\ "<br>fz: %{customdata[2]:.3f}<br>intensity: %{intensity:.3f}<extra></extra>"

the hoverbox that displays data related to the k^th face is anchored at the k^th vertex, i.e. plotly.js associates face attributes to vertices and so hovering is confusing and non-informative.

It would be nice to provide hoverbox pointing to the face centers when a hovertemplate contains information related to faces.

This is a simplest example to illustrate the bug: https://plot.ly/~empet/15474. It has 6 vertices and 8 faces. Plotly makes pairs (vertex[k], intensity_face[k]), k 0,1,2,...5. Hence the face intensity for the faces 6 and 7 are not even displayed.

In the right plot from this example https://plot.ly/~empet/15467 if you are hovering the darkest face, you'll see the non-concordance between the associated color and the displayed intensity.

[archmoj]

@empet
Thanks very much for reporting.
It turned out that there is a similar bug when using facecolor!
Here is a demo.

[empet]

@archmoj I don't remember ever using facecolor, because for a mesh with a big number o faces it's difficult to find and write explicitly so many color codes.

[archmoj]

This issue might be linked to #4533.

[empet]

Thanks @archmoj!

[archmoj]

@empet thank you for reporting!