This step-by-step tutorial will walk you through UVW Unwrapping a hard-edged object using 3DS Max’s inbuilt tools. You’ll learn about overlapped and flipped UVs and some basic UV stitching techniques.

UVW Unwrapping is not difficult at all. It is however, a time consuming and tedious task. We’ll be using a really simple, low-poly pillar prop for this tutorial. You can download the initial scene here:

UVW Unwrap Result Preview

This is a Viewport screenshot of the unwrapped and normal-mapped pillar:

1/4 About Flatten Mapping

Open the scene you’ve downloaded, select the pillar and switch to the Modify tab {}. Add an Unwrap UVW modifier to the stack.

Click the “+” sign next to the Unwrap UVW modifier and select the Faces entry. This allows you to work on a polygon level. Select all the faces of the pillar by pressing ctrl+A or by selection box. With all the faces selected, Enter the UVW Editor by pressing the Edit button

In the Edit UVWs window, press the Face Sub-Object Mode {} button to see your selection. Right now it’s a garbled mess. To separate the mesh correctly, go to the Mapping menu and click the Flatten Mapping entry.

The Flatten Mapping command is an automatic Unwrapping technique that takes the angles of adjacent faces into consideration. So, the cut-off limit for UVW groups is the angle between two adjacent faces. Larger values will create fewer, larger groups while smaller numbers will create a lot of smaller pieces.

Leave the values at default for now and click ok. You should end-up with something like this:

At first inspection, everything seems to look just fine, except the small face that ended-up on a separate group. We’ll need to fix this manually.

2/4 Stitching the Unwrap results

Uncheck the Select Element box and select the stray face. Right Click it and click on Detach Edge Verts.

Use the Move{}  and Rotate {} tools to move the stray Face into place

We need to make sure that it is correctly positioned and flipped. The easiest way to do this is to check the face’s vertices. Click the Vertex Sub-Object Mode button {} and zoom in to our stray face. Select the face’s top-right vertex along with the other group’s vertex.

Check the viewport to make sure that the two vertices are in the same position. If they are, it means that the face is not flipped or turned the other way around.

With the two vertices selected, click the Weld {} button. You can use the Target Weld tool for the other two stray vertices. You should get something like this:

3/4 Further Stitching

When a mesh is split into separate UVW groups there will be seam lines. The fewer the groups are, the less seams you get.

While we stitch the parts up, we need to make sure we don’t spoil the UVWs. Click the Display button and check the Show Edge Distortion entry. This will let you visualize the texture distortions.

> A red edge means it’s completely distorted
> A bright green edge means it’s perfect
> There are various shades between red and green
> A white line on an edge denotes texture stretching (scale the edge down)

We seem to have a few dark green edges. To fix these mild distortions, go into the Vertex Sub-Object Mode {} again and drag the vertices until everything is (more or less) bright green. (Try to keep straight edges straight and compromise between the shades of green and texture stretching).

It should look like this (in time you’ll learn to love green):

Continue on page 2