N-Paint 3D: Map Mode

Using 3D paints map mode, you can paint on a texture map on the canvas and watch your changes applied immediately to objects in the geometry window.

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In this Chapter

• Set up an object for painting in Map mode
• How to paint on an object in Map mode
• How to save your object and maps when you're done

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Map Mode

We called this technique "map mode" because you actually paint on a map and see that image directly applied to a 3D object after each operation. This means that you can work on very complex areas (even areas with obscured faces) in an easy to use environment.

In this chapter, we'll create a simple geometry object, attach a mapper to it, create a map, apply the map through the mapper, then paint on the object.

Preparing the Object

A new sphere appears in the geometry window:

2. (CLICK-L) on Shading in the GeoMenus.

3. (CLICK-L) on Sphere from the object list that appears.

The sphere is now rendered in the geometry window using GL shade:

Note. You must have shading turned on for any object that you want to paint on with N-Paint 3D.

4. (CLICK-L) on New Object>Mapper on the GeoMenus menu.

The new mapper parameters menu appears:

5. (CLICK-L) on Spherical.

6. (CLICK-L) on the Bounds Source field, and select your new sphere from the object list that appears.

7. (CLICK-L) on the Make Mapper button.

8. (SHIFT-L) on the sphere, then (CLICK-L) on Apply Mapper.

Select the spherical mapper you just created. The mapper is now associated with the sphere.

Note: In previous sections, we've applied mappers using the browser. You can use the browser or the GeoMenus to assign mappers; the two methods are equivalent.

9. In the commands section of the Paint tools menu, (CLICK-L) on the File>Create New.

Figure 7.5 N-Paint commands

10. Use the default canvas size (512 x 512), specify a path and filename, and (CLICK-L) on Do It.

11. (CLICK-L) on File>Save to save the new map file to disk.

Note. If you've already created a basic map, you can specify that map instead of this one as indicated below.

Create a Material

12. Open the Attributes Editor

Figure 7.6 The Attributes Editor

13. (CLICK-L) on Materials.

14. (CLICK-L) on New.

The Create New Material dialog appears:

Call this material "3D-Paint-example"

16. (CLICK-L) on Texture in the Material Parameters section of the menu.

Figure 7.8 The Texture button in the Attributes Editor

17. (CLICK-L) on Map.

A Choose File dialog box appears. Use this dialog to choose the map you created in step 11

The operations menu appears.

A menu appears listing all materials currently loaded into memory.

The Assign Mappers dialog box appears:

An icon for your texture map appears in this dialog above a field which specifies the mapper for that texture. This field should show the name of the mapper you assigned to the sphere in step 8. If it does not, (CLICK-L) on the field and select the appropriate mapper from the pop-up menu which appears.

The appearance of the sphere node in the browser changes to reflect the new material attached to it.

If the map you created in step 11 was a plain black image, your sphere should now look something like this:

You're now ready to paint on the object.

22. (CLICK-L) on the GeoPaint button on the menu bar again, to make sure that the appropriate windows are open.

This just makes it easy to arrange the windows on your desktop so that what you need is available.

24. (CLICK-L) on the sphere to select it.

25. (CLICK-L) on Map in the Modes area of the Paint menu:

Figure 7.11 Selecting a paint mode

The geometry of the sphere is "unfolded" on the paint canvas. The vertices and edges in your model become nodes and lines in the N-Paint grid, forming an overlay of your objects geometry on the texture map your painting.

26. Choose a paint tool, such as the round brush with a color ink.

27. Paint several strokes on the canvas.

Note that after each stroke, the object is updated:

Delaying Updates on the Object

When you let up on the ALT key, the modified map is reapplied to the object.

Saving Your Work

• You created the object in the current session and haven't yet saved it.
• You've made changes to the attributes for the object (e.g., changed which map was assigned through a mapper).

To save the object:

28. (CLICK-L) on Save in the GeoMenus.

Specify a directory and name for your sphere and mapper objects, then (CLICK-L) on Do It.

Enter the pathname for where the modified map should be saved:

That's it! You've now saved your object with an attached mapper and a custom map created just for that object.

• selecting a single face or making a collection of faces in the N-Geometry window
• choosing a pre-defined face part from the object

Painting on a Selected Face or Faces

1. Select the face (or collection of faces) on the object you want to paint on.

For example, you might want to paint on one section of the sphere we created earlier:

2. (CLICK-L) on the Map button in the 3D portion of the menu.

The highlighted faces are outlined on the paint canvas:

This is handy if you want to see what portion of the map you're painting on corresponds to a selected part of the object:

Note that even though you've gathered a collection of faces you want to paint on, painting on the map is not limited to those faces. If you want to paint only on certain faces of the object but protect others, you need to use the matte feature described below.

Using the Matte

1. Select the face, collection of faces, or body that you want to protect.

2. (CLICK-M) on the Map button.

A matte channel is created on the paint canvas; to see it, (CLICK-L) on the View button in the Matte modes section of the menu.

3. To use the matte, (CLICK-L) on the Use button in the Matte modes section of the menu.

4. If you want to paint on (rather than protect) the selected faces, you can reverse the matte.

(CLICK-L) on the Rev button in the Matte modes section of the menu. The matte is reversed:

5. Paint on the unprotected part of the canvas as you normally would:

Figure 7.20 Painting on the object using the matte

6. Save your work as described in the section "Saving Your Work," on page 7-11.

Part Select

You might collect the eyes on a robot, or the fins on a rocket so that you could easily select that group of faces with one command. Creating face parts is described in more detail in the N-Geometry Reference Guide.

It's also likely that you'll want to use N-Paint 3D to paint on a pre-defined face part; to choose a face part you want to paint on.

Selecting a Face Part on the Object

1. (CLICK-L) on the Part Select button in the 3D Paint portion of the menu.

A list of face parts on the object is displayed:

2. (CLICK-L) on the face part you want to highlight and (CLICK-L) on Do It.

If "top" was a collection of faces on top of the sphere, it might look something like this:

3. (CLICK-L) or (CLICK-M) (if you want to create a matte channel) on the Map button.

The geometry for the selected part of the object is unfolded as an overlay on the canvas.

1. (CLICK-L) on the Part Select button in the 3D Paint portin of the menu.

A list of face parts on the object is displayed:

2. (CLICK-L) on the face part you want to highlight and (CLICK-L) on Do It.

If "top" was a collection of faces on top of the sphere, it might look something like this:

3. (CLICK-L) or (CLICK-M) (if you want to create a matte channel) on the Map button.

The geometry for the selected part is unfolded as an overlay on the canvas.

Note. Even though only a selected part of the object is visible, if you paint beyond the unfolded overlay for that part, non-visible parts of the object will be updated! The Part Select command only controls selection and visibility of face parts; you must specify a matte channel if you want one (as described in "Using the Matte," on page 7-14.

Making the Entire Object Visible

The 3DPaint-selected Face Part

Figure 7.25 Selecting a face part

The 3DPaint-selected part is redefined each time you (CLICK-L) or (CLICK-M) on the Map button in the 3D Paint portion of the menu.

Note. The 3DPaint-selected face part is not redefined if you copy the geometry of a previously defined face part to the paint canvas.

Using the Overlay as a Grid

Using the Grid

This is useful if you want to perform any operation along the edges of the selected object. You may, for example, want to paint along the edges to highlight it, or create a matte along the edges and paint only the interior of the faces.

Note. Toggling the display of the grid does not turn it off.

Hot Key Summary

Table 7.1 N-Paint 3D Hot Keys (Map Mode)

Keystroke	Description
(SHIFT-G)	Draw and undraw grid
g	Constrain to grid
s	Highlights the faces of the last face part whose geometry was copied to the canvas (including 3DPaint-selected). This hotkey is useful because after you select the faces in geometry and send them over to paint (by clicking on Map), the faces are automatically deselected in the geometry window (so you can see what you're painting). If you need to reselect those faces in geometry (to modify the collection) you can use the [s] hot key.

Copyright © 1996, Nichimen Graphics Corporation. All rights reserved.