3D modelling can become repetitive, particularly with symmetrical items. Imagine having to model Sackboy’s right arm and then doing it again for his left? It’s inefficient. For this reason, any good 3D modelling program provide what are called modifiers.
Now that we’ve created the head and torso, we’re going to delete half of it and use a “Mirror Modifier” that will mirror the work we do on the left, over to the right. Start by selecting all the vertices on the right-side of your object (not including the very center) then hit “Del” > “Vertices“:
Your model should look something like mine above. The only problem now is that the very top and very bottom no longer have faces since we deleted some of the vertices they required, so go to the top of your model, select all the vertices around the empty hole and press “F” to (in this case) create a face:
This will place a face (and the missing edge) where it is required. Repeat that process for the bottom so we have a complete half-mesh.
Now we need to add the appropriate modifier to our project. In the main menu on the right of your workspace, you will notice a row of icons, we need to select the one titled “Object Modifiers” (it looks like a spanner/wrench):
Now we have the option to Add Modifier…see if you can find and add the Mirror modifier and then alter the settings like such:
Notice that I’ve chosen to mirror the X-axis, I’ve selected the Clipping option which just ensures any overlapping vertices/edges/faces are “fixed” by Blender and I’ve also selected the option at the top that means the editing cage is visible. So now your model should look just like it did prior to deleting those vertices:
The beauty of our new modified mesh is that any changes we make to the left, are automatically applied to the right. You can also show or hide this modifier by simply clicking on the “Eye” icon located in the Mirror Modifier window.
Hopefully this clarifies why we didn’t want to move Sackboy’s center (Z) axis from the front, if we did then the mirror wouldn’t have lined up well and our mesh would not have been overly clean. Forward planning when modelling is essential!