1.1 Introduction
1.2 Commands
2. Unfolding step by step
3. Cutting
3.1 How to cut ?
3.2 Where to cut ?
4. Adjusting and packing
5. UNFOLD3D Interface
5.1 Menus and tools
5.2 The menu bar
5.3 The main toolbar
5.4 The viewport toolbar
5.5 The edition toolbar
5.6 Preferences
6. UV Edition
6.1 Rotation/translation/scaling
6.2 Pinning
6.3 Horizontal, vertical constraints
7. Scripting
3.2 - Where to cut?
Unfold3D deals with mathematic equations, not with magic formulas. This means that it manages to solve the problem of flattening a surface -without too much distorsion- only when the surface can be flattened. This is why the cutline is so important: a good cutting line will allow to flatten very distorted areas, while limiting the number of joints on the model.
A simple example
What happens if you want to unfold a tube? A tube can actually be unfolded "as is": the two ends of the tube are openings. But such an opening would produce a very bad UV mapping of the tube: one of the two ends would be overstretched while the other one would shrink, and the number of pixels from a texture assigned to each zone would be incredibly high in one case and incredibly low in the other.
If you try to flatten the tube as on the picture, the two squares have
same size on the cylinder, but very different sizes on the unfolding
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To avoid such problems, you would rather cut the tube along one side. Unfolding the tube is then pretty immediate, and you obtain a perfectly reparted mapping, well spread over the surface of the model. |
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Where to cut out?
The cutline should split tube-like and sock-like shapes.
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| cut open tube like-shapes | cut open sock-like shapes, either of two ways |
The cutline should be in one piece.