Line orientation changes when rotated; unexpected behavior

[kanihoncho]

The problem is that the line has a rectangular (or square also, I suppose) "shape" assigned to it with handles. The line follows a vertical or horizontal side of this shape.

Once the line is rotated the line no longer follows the vertical or horizontal side of the "shape", it now goes from corner-to-corner which changes it's length, and requires that one also has to rotate it to find the new angle to make it "90 degrees".

This happens when you use the transform panel and the Top Menu > Layer > Transform > Rotate Right command. 

Edited July 22, 2019 by kanihoncho
for clarity

[Hangman]

Hi kanihoncho,

This is because you have an offset between the top and bottom points of your line which means your initial line isn't completely vertical.

When your line is in the vertical position if you select the top node of the line with the node tool and look at the 'X' coordinate and then compare that to the 'X' coordinate when selecting the bottom node you'll see the two are slightly different which is why your line has a width. If you set both 'X' coordinates to the same value or redraw your line and hold the Shift key whilst drawing then you will no longer have the rectangular "shape" assigned to it with handles, you'll simply have a central line with a single selection handle at the top and one at the bottom.  This means when the line is rotated by 90 degrees it will be perfectly horizontal.