Use old curve setpoints for offsets

[ksunden]

Closes #52 Closes #69

[ghost]

DeepCode Report (#424091)

DeepCode analyzed this pull request.
There are no new issues.

[untzag]

@ksunden can you describe in paragraphs what this PR does?

[ksunden]

The problem with the plotting is that the x-values of the offsets are incorrect.

Upon looking at the code again, I realize now that part of the problem is that the map_setpoints call occurs after the plotting.

The line being plotted is splined offsets from the input curve.
It was being plotted with the output curve (pre-remap) tune points, thereby showing the offsets as being offset from the correct value, instead of to the correct value

In cases with small offsets, this difference is hard to percieve.

If it had occurred prior to plotting, with the current arguments, the two arrays being switched here would be equivalent.

I will update this PR to move the map_setpoints call to before plotting, however I still wish to make the change already in this PR, as the ideas like in #60 and #68 would re-introduce this otherwise.

This is an example of something that is difficult to test against, as it is purely visual, no changes in the actual output.

[untzag]

thanks I understand now