Bissector guide

[fdesar]

I use Inkscape for quite a while and in the kind of drawings I have to do (origami diagrams) I need a zillion times to draw a guide which
simply bissects two straight paths, i.e. two crossing guides or a the angle XYZ defined by the path of nodes x, y z. I found a way to do it but
as logical as it is, it request a lot of actions :

- create two guides, G1 for the xy path and G2 for the yz path
- move them away so they cross in a free space of the workspace
- draw a path of any length P1 following G1 beginning where G1 and G2 intersect
- duplicate the P1 to get P2 so it has the exact same length as P1
- move P2 rotation center where G1 and G2 intersect
- rotate P2 along G2
- draw a guide G3 centered on the node at the free end of P1
- rotate G3 so it go through the node of the free end  of P2
- draw a path P3 of any length anywhere along G3
- rotate 90° P3
- Shit-G to finally get the expected guide G4 which bisects the angle xyz

The is perfectly accurate but really tedious, specially when I have to do this a lot of time a drawing
and request me to create each time three unneeded guides and three unneeded paths I have to discard.

Of course, another way is to create G1 and G2, get their angles pick up my calculator to compute the
bissector angle... but this is not satisfactory to me as I prefer to concentrate on drawing than computing


My only question is : does someone know a simpler way to achieve this result an Inkscape way I didn't think
or was aware of ? Any tool, tip or so ?

Thanks for your time and sorry if this question is already answered somewhere I didn't find or finally
completely trivial.

[Moini]

If the Inkscape development version weren't so buggy, you could use that one - it has a tool for bisecting angles (and it crashed on me twice while trying it out, and behaved strangely most of the time).

But yes, there is an easier way:

- Drag guide out of the ruler and snap its origin to the crossing of the two lines which you want to bisect (snapping to path intersections needs to be activated, as well as snapping to guides)
- Hold Shift and rotate it, until it snaps to one of the lines (snapping to paths must be activated, or snapping to cusp nodes can be used here, too)
- Double-click on the guide, copy the angle that is indicated there
- Hold Shift and rotate it again, until it snaps to the other line
- Double-click again. Add "(" in front of the angle, then add "+" after it, paste the angle you copied behind, close the parenthesis with ")" and type "/2".

This will make the guide bisect the angle.

[fdesar]

Many thanks Moini!

It seems it works perfectly, even when you add negative angles (i.e. 12.8+-23.43)/2) and it solves quite
cleanly my question : no more unneeded guides or path created and really fewer steps (and not much to think of to do it )!

With the few tests I made, it didn't crash, so let's hope it was a solved bug...

I just never imagine I could ask computations in guides angle values...: shame on me !

It closes then happily my request.

Many thanks and best regards

[Moini]

The crash is with the LPE tool in the development version, not with rotating and snapping guides manually

(with the LPE tool, you just click three times, and it will draw the bisecting line for you - but it's not available yet)

Happy origami pattern making

(if you like, you can upload an example of what you do with Inkscape to our gallery at https://inkscape.org - I'm always interested in seeing what people do with Inkscape)