Flip objects along a custom angled axis.

[Dewlally]

I design pop-up books and would like to use Designer as a replacement for Vectorworks CAD software I have used for the last 20 years, but has become prohibitively expensive since it switched to a subscription only version.

One simple function I need a lot that's missing from Designer is the ability to flip objects along a custom angled axis – not just horizontally or vertically, which I know Designer can do.

In the screen shot below, I'd like to a tool that allows me to flip the object along the dotted line between A and B, ideally simply by clicking and dragging a flip axis line between A and B.

I understand that a similar function is available in Adobe Illustrator, but at the moment, the quickest way I've been able to do this in Designer is by duplicating the object, flipping it horizontally and moving and rotating the duplicate until the two axis lines line up, which is a lengthy workaround.

I've seen other people requesting this function in this post: https://forum.affinity.serif.com/index.php?/topic/59694-can-i-flip-mirror-a-shape-through-a-pointaxis-of-choice/

 

[loukash]

+360!
Just recently I was fighting with a similar issue…  

On 1/13/2023 at 7:27 PM, Dewlally said:

the quickest way I've been able to do this in Designer is by duplicating the object, flipping it horizontally and moving and rotating the duplicate until the two axis lines line up, which is a lengthy workaround.

You can speed it up by selecting the A & B nodes with the Node tool and copy their rotation angle value (R) in the Transform panel. In case that's an open curve with no stroke between A & B, draw a temporary line to copy its angle.
Duplicate the object and flip horizontally.
Align the duplicate so that both B nodes snap. Use the alignment handles, that's faster.
Snap the duplicate's Transform Origin to node B.
Rotate duplicate by (90-R)*2 

[lepr]

Point Transform Tool (f) easily solves the problem without needing a helper line and messing around with rotation values and calculations.

[Dewlally]

13 hours ago, loukash said:

+360!
Just recently I was fighting with a similar issue…  

You can speed it up by selecting the A & B nodes with the Node tool and copy their rotation angle value (R) in the Transform panel. In case that's an open curve with no stroke between A & B, draw a temporary line to copy its angle.
Duplicate the object and flip horizontally.
Align the duplicate so that both B nodes snap. Use the alignment handles, that's faster.
Snap the duplicate's Transform Origin to node B.
Rotate duplicate by (90-R)*2 

Thanks. I think this would take a similar time to the method I use (which is only outlined above). Here it is in detail:
I group the object with the axis of reflection line.
Move the grouped object's transform origin to point A.
Duplicate the grouped object and flip the duplicate horizontally.
Move the mirrored duplicate so that its transform origin (point A) is on the transform origin of the original grouped object.
Rotate point B on the mirrored duplicate to point B on the original grouped object. 

When I use Vectorworks to do the same thing, I simply have to select the object, select the mirror and duplicate tool and then click on point A followed by point B. It would be great to have something similar in Designer. 

[Dewlally]

20 minutes ago, ,,, said:

Point Transform Tool (f) easily solves the problem without needing a helper line and messing around with rotation values and calculations.

I can't see any way to flip the object using the Point Transform Tool.

[lepr]

14 minutes ago, Dewlally said:

I can't see any way to flip the object using the Point Transform Tool.

You still need to use Flip Horizontal, then the procedure with PTT is essentially what you're doing in your own method, but it doesn't need a helper line and the rotation will snap the objects together precisely.

[Dewlally]

1 minute ago, ,,, said:

You still need to do the flip manually, then the procedure with PTT is essentially what you're doing in your own method, but it doesn't need a helper line and the rotation will snap the objects together precisely.

Thanks. The green line in the screenshot is a fold line in the pop-up (the red lines are cuts), so it's an integral part of the drawing, not a 'helper line", but I get that I can mirror the object without it.

[carl123]

15 minutes ago, Dewlally said:

I can't see any way to flip the object using the Point Transform Tool.

This simple GIF from PixelPest may help

 

[loukash]

1 hour ago, ,,, said:

Point Transform Tool

Thanks for the heads up! That tool is for some reason always off my radar.

That said, the (helper line) angle method will always work outside Designer when there's no P.T.T. available.

[lepr]

1 minute ago, loukash said:

That tool is for some reason always off my radar.

PTT was one of the most useful additions during the AD 1 period, in my opinion. Thankfully, its multitude of modifiers are shown in the status bar.

My favourite tools so far introduced by AD 2 are the Shape Builder, Knife and Cut Curves With Key Object. Of course, these tools are built on the greatly improved (other than a few teething problems) boolean operations of AD 2.