Mirror by custom pivot

[PuChiNgBaLLz]

Hi there, i saw this question in the forum since 2013, but there were no answers, is it possible to mirror an object through a custom pivot position and angle? i set the custom pivot to match center line of another object, but the rest of the model is rotated so axis cant be regular object or world. If this is not possible by feature it should be by now, it's already implemented in many autodesk softwares like inventor, this could be achieved by selecting any of the current custom pivot xy, xz or yz planes as mirror from it's center or even a custom displaced point from custom pivot center

[Kahylan]

Hi!

If you want to mirror an object by another objects pivot, you can use a group to do that. Create an empty group (Create>Empty Group), snap that group to the object you want to mirror on, using a parent constraint. To do that select the object you want to mirror on first and then the group and use the ParentConstraint command (Rigging Toolset, Constrain>Parent, make sure the "maintain offset" box is turned off). Then duplicate the object you want to mirror, place the duplicate into the group and set the groups scale on the axis you want to mirror on to -1. After that you can unparent the duplicate and simply delete the group.

It's a few steps but if you've done them once or twice you'll be pretty fast by using the shortcuts. But I would still try to generally stay with my objects symmetry on one of the main axis as long as possible while modelling.

I hope this helps!

[PuChiNgBaLLz]

Everything is done but, once the duplicated object is inside the group if i want to align the group pivot to a custom edge, the duplicated mesh rotates around. 1st image before alignment 

2nd after aligmen, in outliner is selected the group

It should be mirrored in this side 

[Kahylan]

Ok, I assumed that the object in the middle of the bike actually is alinged with the front of the Bike, in which case modifying the rotation of the object would not be needed. Also you should not use the pivot mode to change your groups pivot, but just regular movement. Which is blocked by the constraint, but since you only need the constraint to snap to your object you can delete it right after you create it. I attached a video on what I meant in my first post.

If you don't have an object you can mirror on and you need to mirror on a specivic edge, you can use a motion path constraint instead of a parent constraint to align your mirror group with the edge. by converting the edge to a curve and using this curve ad the driver of the motion path. I attached a video on that as well

I hope this helps!

[PuChiNgBaLLz · Accepted solution]

Thanks for the reply, but i found the simplest solution, it's by editing the object pivot with Ctrl key pressed to orient it to a specific direction, and this affects the object level pivot, so no Custom one is used. In both methods above didn't work since the empty group as the curve extracted were object pivot matching world pivot, so the reflection still performed in the wrong direction, followed exactly the same steps, so my only option was to have a correct pivot position to mirror. Since in edit mode, pivot will change to Custom if "aligned" just press Ctrl to "orient" the current one, this while Object pivot mode selected.


Edit: Actually, what keeps the Object pivot level is the Bake pivot orientation checkbox, otherwise it will still change to Custom pivot.