Materials and Mapping Tutorials > Mapping Characters with Unwrap UVW > Creating Clusters for a Character Skin >
Peel the Geometry

With the seams added to the model, you can use the named selection sets to break the model into clusters and lay the clusters out as evenly spaced peels.

Set up the model:

1. Continue from the previous section, or open cman_uv_clothing_seams.max.
2. If you opened a new scene, select the CMan model then go to the Modify panel.

Peel the left arm:

1. On the Modify panel Selection rollout, click (Polygon) to go to the Polygon sub-object level.
2. On the main toolbar, open the Named Selection Sets drop-down list, and choose arm left from the list.

   3ds Max Design highlights the polygons in the left arm.

   The Unwrap UVW modifier will create a cluster out of the selected polygons. When you peel the sleeve, which you will do in a moment, the Peel tool uses the seam you created at the bottom of the sleeve to flatten the way the cluster is mapped. Unwrap UVW also creates "map seams," which you don't have to specify explicitly, at the edges of the selection set.

   ImportantThe seams you explicitly created in the first section must end at the edge of the face selection. If the seam falls short, the cluster mapping will have a closed loop and be difficult to work with. The seam should divide the entire selection: Picture the peel as a paper label on a bottle or a can.
3. On the Modify panel Edit UVs rollout, click Open UV Editor.

   3ds Max Design opens the Edit UVWs dialog. The selected polygons appear in red.

   TipResize the dialog so you can see all of the geometry.
4. On the Edit UVWs dialog upper toolbar, click the options button.
5. In the Unwrap Options dialog Display Preferences group, click to turn off Tile Bitmap, and then click OK.

   This makes it easier to see the unit square of the U and V coordinates.

6. On the Edit UVWs dialog Explode rollout, click (Break).

   This breaks the cluster at the border of the Polygon selection.

7. On the Edit UVWs dialog Peel rollout, click (Quick Peel).

   3ds Max Design peels the sleeve from the seam, creating a flattened cluster.

   This is the kind of cluster shape to which you can easily apply a texture. After some more adjustments, you will improve its layout.

   NotePeel uses a method called Least Square Conformal Maps (LSCM). It appears on the Undo/Redo stack as LSCM.

Isolate the clusters:

Before you adjust the peel of the left arm, rearrange the clusters in the Edit UVWs window.

1. On the Edit UVWs dialog upper toolbar, click (Move Selected Subobject) to activate it.
2. On the first of the Edit UVWs dialog lower toolbars, the Sub-object Selection toolbar, click (Select by Element UV Toggle) to turn it on.

   When it is on, the button shows a check mark.

3. One by one, click the other clusters in the Edit UVWs window, and move them away from the peeled sleeve. Leave the sleeve where it is.

   In general, you don't want the clusters of a peeled model to overlap.

4. Select the peeled left sleeve once again.
5. On the Edit UVWs dialog Sub-object Selection toolbar, click (Select by Element UV Toggle) once more to turn it off.
   ImportantDon't neglect this step! In the next procedure you use Peel Mode, and while Peel Mode is active, Select By Element pins more vertices than you need to pin (we explain pinned vertices in the next few steps).

Set up pins:

1. Use (Zoom To Region) to zoom in on the peeled sleeve.

   Navigation tools are on the Edit UVWs dialog second lower toolbar, the Transform/Display toolbar. They appear in the lower-right corner of the dialog.

2. On the Edit UVWs dialog Peel rollout, click (Peel Mode) to turn it on. Peel Mode keeps peeling this cluster until you turn off Peel Mode, even if you select another part of the polymesh.
3. On the Edit UVWs dialog Sub-object Selection toolbar, click (Vertex) to go to the Vertex sub-object selection level.
4. Click and Ctrl+click to select the two vertices at the top and bottom of the sleeve, the ones with the least and greatest V-coordinate values.
5. In the Edit UVWs dialog Peel rollout Pins group, click (Pin Selected).

   3ds Max Design displays blue boxes around the pinned vertices.

6. Click to deselect the vertices, then click a pinned vertex and move it.

   Notice that the other pinned vertex doesn't move, but the rest of the vertices move in relation to each other. This is because Peel Mode keeps peeling the cluster while you move the pins.

   Peel Mode spreads the UVS among pinned vertices on the cluster. Because at least two pins are needed, the Unwrap UVW modifier chooses two invisible pins by default. If you move a vertex, Auto-Pin Moved Vertices automatically pins it. If there is only one pin, the other pin will still be invisible and chosen automatically. This can change the shape of the cluster in unexpected ways, so it's a good idea to pin two vertices yourself, at the perimeter of the cluster, before you begin to move other vertices.

   TipIf moving a pinned vertex moves the entire cluster, deselect all vertices and then click the vertex you want to move.
7. Move the two pinned vertices so they align a little better with the checker grid.

View the mapping in the viewport:

It helps to compare the work you are doing in the Edit UVWs dialog with the mapping as it appears in the viewport.

1. Move the Edit UVWs dialog and adjust the viewport so you can see both the dialog and the model in the viewport.
2. On the Edit UVWs dialog upper toolbar, open the texture drop-down list, and choose Checker Pattern (Checker).

   Choosing this from the list causes the checker texture to display in the viewport.

   As the viewport shows, the layout of the left sleeve already looks fairly good. The right arm and torso need more work. You will get to these later in this lesson.

Finish the layout of the left arm:

1. Move individual vertices so the layout of the sleeve is roughly rectangular, and better aligned with the checker grid.
   ImportantMake sure that in the Pins group, (Auto-Pin Moved Vertices) is turned on. When this option is off, you can move only vertices that are already pinned.

   These adjustments don't have to be precise. Look at the model in the viewport to see that the peeled sleeve is mapped fairly evenly, with no obvious distortion.

2. Click (Peel Mode) again to turn it off.

Peel the right arm:

1. On the Sub-Object Selection toolbar, click (Polygon) to go back to the Polygon sub-object selection level.
2. On the main 3ds Max Design toolbar, open the Named Selection Sets drop-down list, and choose arm right from the list.
3. On the Edit UVWs dialog Peel rollout, click (Reset Peel).

   3ds Max Design peels the sleeve cluster, flattens it, and normalizes its scale as well.

   The geometry of the right arm is different from that of the left arm, so the peeled cluster has a different shape.

   Reset Peel is an alternate way to flatten a selected cluster, instead of clicking Break and then Quick Peel or Peel Mode.

   Warning Be aware that if you are not at the Polygon sub-object level, or if no faces are selected, clicking Quick Peel, Peel Mode, or Reset Peel resets all peeled groups that are affected by Unwrap UVW.
4. On the Edit UVWs dialog upper toolbar, click (Freeform Mode) to activate it, and move and scale the right sleeve cluster so it is above the left sleeve cluster, and is roughly the same size.

   In Freeform Mode, the sub-object selection is surrounded by a box. Dragging the center of the box moves the selection; dragging a handle in the middle of a side rotates it; and dragging a handle at a corner scales the selection, relative to the texture you are mapping. Watch the cursor to see which transform is active.

5. Turn on (Peel Mode), then click (Vertex) to go to the Vertex sub-object level.
6. Adjust the layout of the right sleeve as you did the left.

   Check the new layout in the viewport.

7. Click (Peel Mode) again to turn it off.

Peel the legs and torso:

Peeling the legs and torso is almost the same operation. The main difference is that because the cluster is large, and because you rotate the selection, you use more initial pins.

1. Click (Polygon) to go back to the Polygon sub-object selection level.
2. On the main 3ds Max Design toolbar, open the Named Selection Sets drop-down list, and choose torsolegs from the list.
3. On the Edit UVWs dialog Peel rollout, click (Reset Peel).

   3ds Max Design peels the torso and legs cluster, flattens it, and normalizes its scale as well.

4. Use the (Freeform Mode) tool to rotate the cluster and place it in the empty area at the lower right of the Edit UVWs window.
5. Turn on (Peel Mode), then click (Vertex) to go to the Vertex sub-object level.
6. For this cluster, click and Ctrl+click to select four points to pin: The two at the very top, which correspond to the back of the collar, and the two at the widest point of the legs, which correspond to the crotch of the pants where the inseam meets the back seam. When you have selected these four points, click (Pin Selected).

   Picking new pins will Peel again, changing the shape a little to spread UVs between the pins.

7. Move the two pinned points at the collar farther apart, to spread the cluster more evenly across the checker pattern.
8. Also move the points at the corners of the cuffs of the pants, spreading them apart a bit and making the distribution more even.

   Don't worry that the cluster extends beyond the unit square.

9. As before, check your work in the viewport to see that the texturing is even.
10. Finally, turn off (Peel Mode), activate (Freeform Mode), and click (Polygon) to return to the Polygon sub-object level. Select the torsolegs cluster once more, and scale it so it fits within the unit square.

    With clusters peeled and adjusted like this, you can create a texture to match the cluster layout, using either an image-processing application such as Photoshop, or the 3ds Max Design Viewport Canvas tool, which lets you interactively paint directly onto geometry.

    A texture for the CMan clothing and hands

    This uses a somewhat different layout from the version you created in the lesson.

    CMan with pants and jacket textured

Save your work:

- Save the scene as my_cman_peeled.max.

  The file cman_uv_clothing_peel_done.max contains a finished version of the peeled model.

Summary

This tutorial demonstrated

- How to use Unwrap UVW to map a texture.
- How to map cloth objects by placing Unwrap UVW on the stack above the Garment Maker modifier but below the Cloth modifier.
- How to create seams for use with the Peel and Pelt tools.
- How to use the Peel tools to lay out clusters in the Edit UVWs dialog, and how pinning vertices helps you adjust the layout of a peeled cluster.