This plugin is what I define as charityware and can be freely distributed.
If you find it useful make what you feel as an appropriate donation to your favorite charity.
You cannot charge or make any money from this routine by reselling or bundling them with
another package/cd/web page without my permission.
To install this routine just copy the files into your 3ds Max plugin directory.
This is a modifier that lets you mirror texture vertices, material ids and smoothing groups across a mesh. Basically you select the faces that you want to mirror to and pass them to the modifier.
The limitations are that it must be a tri-mesh, the modifier should not be instanced if you uses a mirror node, and for best results make sure your selection does not cross the mirror plane.
v1.1 fixes a bug with the Copy Stray Vertices options
Map Channel is the map channel that you want to mirror.
Mirror Axis is the axis that you want to mirror on in local space.
Offset lets you slide the mirror plane along the mirror axis.
Use Node as Mirror Plane lets you pick another object to use as your mirror plane in case the faces that you want to mirror to are not aligned to the local axis.
Threshold is a fudge factor used to as a tolerance to determine which faces and vertices match across the mirror plane.
Copy MatIDs will copy the material ids in addition to the texture vertices of matching faces.
Copy Smoothing Groups will copy the smoothing groups in addition to the texture vertices of matching faces.
Instance Mapping TVs will force the mirror to texture vertices to share the same texture vertices. If this is off a copy of the texture vertices will be made.
Copy stray vertices initially only faces that are symmetrical across the mirror plane will be copied. If this is on after the faces are copied any stray vertices will be copied. This is useful if your object is symmetrical point wise but not face wise.
An example of usage is to create a 14 segment sphere and collapse it to an edit mesh.
Apply an a checker material to the sphere.
From the front of the sphere and select half of the sphere faces and apply a planar map. So it looks like the image below.
One thing to notice is that the points are symmetrical but the faces are not. Collapse back to an edit mesh and select the other half of the sphere.
Apply the MirrorTVs modifier.
Your sphere should now look the image above with the texture vertices mirrored. If you notice the gizmo the orange marker are the selected face vertices mirrored across the mirror plane. Faces with a yellow edge are faces that successfully got matches, while yellow + vertices are vertices that got successfully matched.
Now turn off the Copy stray vertices notice that the center band of faces now don’t get mirrored because these faces are not symmetrical. Since these are not symmetrical faces only vertices can be copied.
Note this utility has not been fully tested in a production environment so use at your own risk. If you encounter any problems please contact me at