UV-ing is necessary but a very particular type of work in 3D art. Like mentioned above ‘sort of’ setting up your models (meshes) to make UVing easier is the real key.
What I am about to say may get some 3D Atlas zealots wriggling in their seat but…keep your atlas textures to a bare minimum or do not use them at all. What I am saying…repeated…only use atlas textures where absolutely necessary.
Example: I will use 3DForge in the Unity Asset Store as an example. He makes really good 3D art for gaming. The meshes are clean and well positioned. The textures he decided to make an atlas so he could use the same texture on a lot of different meshes. The end result is quite good with a 4k texture being the atlas. Coupled with an excellent normal map and the meshes look really good in game.
Issue #1 with this method is…making texture changes for multiple options is a royal pain. You have to change only a portion of the texture and leave the rest. So what ends up happening is layering textures in the shader with transparency over the base texture. You need slots for each part you are going to change…so where are the savings in making the atlas in the first place? Basically for those who will have no options.
Issue #2 with this method is…parts of a mesh end up using the same UV on multiple sides of a mesh. This makes it difficult to ‘see’ what is going on with the UV when getting seams or other artifacts that need minor tweaks.
So the Modelling 101 is to make 1 texture with 1 UV per mesh. If an item like a sword or gun as examples have a couple parts to them…keep the number of meshes below 5 and make an atlas for them. This makes it 1 draw call for the mesh as it should be. Use this when making your meshes and the UVing becomes very simple and 99% automated.
Here are two tools that I highly recommend for really good automatic UV Unwrapping. There are a number of programs that have UV Unwrapping Algorithms but these seem to be more general purpose for very simple meshes.
*Blender does an OK job at UV Unwrapping in the latest versions. still needs pulling around to get them easier to match the textures.
*MayaLT does no better than Blender
*Lightwave has a UV Plugin that does no better than Blender.
Both of these below are also WYSIWYG.
Ultimate Unwrap 3D - $60
This one also makes UVing really easy. The results are very good even on complicated meshes…especially if using simplified meshes as stated above.
Headus UV Layout - $200
This one makes UVing actually fun. It is UVing the easy way. Almost fully automatic and making adjustments is just simple. This one does more complicated meshes with A LOT less work.
*Get the Hobbyist version
- Simplify the meshes
- Use a tool dedicated to making UVs to save yourself a lot of headaches