RfE: native Mirror Tool



add a native mirror tool for mirroring along point/axis/plane to the transformation tools of the edit toolbar.

How to mirror in sketchup

Personally I like the stretch tool way of mirroring: I find it really intuative to start dragging a node and type in “-1”. (Tip: If you hold [ctrl] while starting to stretch, it will flip about the centre of the selection.)

The only down side is that you have to “copy”/“paste in place” to have a duplicate mirrored.

It would be nice to be able to define a mirror plane and just drag a node to mirror (tapping [ctrl] to make the mirror a duplicate of the source like copy/move/rotate does)


For many years, there has been an Extension that does this http://sketchucation.com/pluginstore?pln=Mirror


I know but core transformation tools as a mirroring should be avail as a native tool of SU.


MANY things aren’t built-in…
Why choose just one omission ?
I can think of lots, but then we start getting an AutoCAD or Word app, which we mainly agree is not what we want…


Hi sketch3D_de, hi folks.

Click in sequence on the scene tabs of this SU file for ideas.


Mirroring_relative_to_a_plane.skp (42.5 KB)


Right clicking on an axis enables you to adjust the drawing axes numericable. Or by using ‘Axes’ icon -> “Move or reorient the drawing axes.” Thus enabling to creating the desired plane to mirror a selection (except for single group or component, … other solution).
I think that knowing how SketchUp works is good enough to do the simple desired mirroring with basic tools. Any new native mirror tool would make SketchUp less “simple”.
Also see (sort of same workflow) Jean’s example where he uses ‘Align Axes’ to a face to redraw the axes.


‘ease of us’ is the key asset of SketchUp.

The “less simple” workarounds described above as well as the existence of the plugin and also the recent Skill Builder video concerning mirroring seems to show a need for the feature requested.

Every application targeted to Computer Aided Design should incorporate the 4 core transformation tools move, rotate, mirror, scale/stretch as dedicated tools.

Adding such core functionality does obviously neither lead to a full blown 2D drawing program nor a word processor and would in contradiction impose the question why other less important functionality has been added in the last versions.


I agree that ease of use is what SketcUp is really about. However I don’t know if I would consider mirror a core transform concept. It’s just a specific case of scaling. In programs where you can’t type in exact scale factors and scale doesn’t snap to -1 a separate tool is very much needed but when scale is designed correctly from the start I don’t think it is.

I think the downside of having more icons in the toolbars which can be overwhelming to new users outweighs the upside of the additional tool. In my view rotated rectangle shouldn’t even be its own tool. Having just one rectangle tool and use hold+drag to set a corner adjacent to the start corner while click+move+click sets the opposite corner directly would be better and more consistent to the rotation tool.


mirroring (flipping around a point/axis/plane) is scaling (changing geometric dimensions keeping the orientation)? huh


Mirroring is just scaling by -1. It is not a different concept. Also I don’t know what you mean by scaling keeps orientations. When scaling a vector that isn’t orthogonal to the scale axis its direction changes. If you scale by a factor less than 0 all vectors parallel with the scale axis will also be reversed.

However I’d be happy to see more control for what point/axis/plane you use as anchor for scaling, regardless of wether you want to scale by -1 or any other factor.


Isn’t that the ‘Axes’ tool? I know, it’s an extra step before you mirror.
But even with a new ‘Mirror’ tool setting that plane is just an incorporated extra step instead of being outside the ‘Mirror’ tool.


Axes tool can be used to change the axis to scale in but not an “anchor”/scale origin. You either scale around the centroid or the handle onsite to the one you grabbed. The axes tool also permanently modifies the axes when used inside a group so it isn’t very useful for this.

I really like how rotate tool both lets you hold down and drag the mouse to set a rotation axis and click to use the normal of whatever you clicked. Something similar in scale too to allow for both easily scale along the axes, as you currently do, and be able to set a temporary axis and scale origin would be great!


but scale to work nicely for productivity as a mirror tool you need to be able to set the axis to the world coordinates (mirroring 1/2 of a complex roof, for instance, or mirroring a complex valley or hip rafter in my work) - otherwise the inbuilt sketchup scale tool would mirror a -1 about the axis of the component, which I generally set along the width and length of the building material I am modeling, for ease of manipulation.

so, a true mirror tool to be useful would:

  1. make a copy or the object
  2. allow you to select the mirror plane
  3. reference any geometry or coordinates you wish when selecting the plane

TIGs mirror plugin does all this. and I seem to remember that I can modify the code to speed up the acceptance dialog at the end if I wish…


Haven’t you just described my Mirror tool ??


I do believe I said that in the post above…


FTR, I am in favor of the original FR.