Plotting functions on splines should be evaluated with physical coordinates.

[jzwar]

Current Behavior

When plotting functions on splines, evaluation is currently performed at the parametric coordinates of the spline. This can be unintuitive and potentially confusing. However I see a use-case (see the isophotes example).

Proposed Change

Make the current behavior optional, with evaluation in physical space as the default. This would make plotting functions - especially on Multipatches - more intuitive and user-friendly.

❓ Curious to hear your thoughts on this — especially regarding potential performance implications or cases where parametric evaluation is preferred.

[j042]

Can you give me an example of evaluation in physical space?