Curves, Splines and correct use thereof

Newbies
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Hello all, I have some questions about the use of splines (here : Interactive) :

I have, as an example, set several points on a curved line (which is actually a circle, but I needed a simple template). These points are to be connected on a spline:Interactive (CNTL+S) as shown in the first graphic:

image

Here I have simply joined the point (anti-clockwise) with the Interactive Spline Tool … Easy!

image

For reasons only known to me, I wanted to make the curves effectively mirrored (without using the mirroring function in Seamly2D for now). So I made two separate splines from E7 to E2 in opposing directions.

Now, to my question(s)

When selecting the spline as an element when creating a new piece - and the selection is to be done Clockwise (I hear) does the indicated spline direction (arrows) have any effects on this process?

EDIT #1: I have now taken the time to experiment and found that this is indeed relevant!

Apart from the slight increase in effort involved in making two splines - which is easer for me at this time - to ensure complete and accurate mirroring of the two halves?

If I were to actually use the Mirror Tool, are any of the formulas also copied, or is the mirror-image corrected when the original is altered in any way?

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The Mirror Tool mirrors the elements’ current positions, not their position at the time of using. So the Mirror Tool should only be used when you know that the mirror image of the elements is what is required.

This sentence doesn’t parse. But assuming that you’re asking “[What is the best way] to ensure complete…” due to fuzzy math reasons, I assume that mirroring is more 1:1 so if you’re mixing Mirroring & mirror-drafting, Mirror first & draft off that, because the Mirror probably won’t perfectly align with the mundanely drafted elements, so you’re likely to get weird seamallowances.

:arrow_right: Oh yes, & you can always hold Shift while clicking curves to reverse the trace direction.

:unicorn:

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Thanks for responding, we’ll have to agree to ‘disagree’ about the syntax / parsing … it still makes sense to me, or maybe that’ because I know what’s going on in this befuddled brain (and can mentally ignore the question mark … my bad). :wink:

And thanks for the tip about ‘Shift’+‘Click’ :smiling_face:

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