Gilles Tran wrote:

> Real-time 3D painting and automatic unwrapping are two different features.

Okay fair enough, I really wasn't confused about that but as I try to 
explain myself further, I see that my question was more complex than it 
seemed at first.

In the whole uvmapping process, is about relating 2d information, a 
pattern of colors, to 3d information, a surface which carves through 
space, via the use of intermediary 2d uv coordinates. In  this way the 
3d surface can be colored with a specific pattern. Techniques and the 
interfaces which support them, traditionally try to picture the 3d 
surface flattened onto a 2d uv register in the form of a pattern or 
template.  But doing this by simply collapsing one of the 3 dimensions 
usually leads to a tangled pattern of mappings, between vertices and uv 
coordinates, which then corresponds awkwardly to any coherent pattern of 
colors.

So instead, the 3d surface is "unwrapped" by splitting edges 
systematically along well chosen lines, so that the surface being 
colored can be spread out, so to speak, onto the 2d register in the most 
coherent way.  Now the pattern of color can be more easily corresponded 
to the pattern of uv coordinates, and hence mapped to the 3d surface.
This unwrapping process is supported by tools native to modellers or 
independently such as uvmapper, and can support processes that are 
'manual' and 'automated' to varying degrees. Some strategies for 
splitting up the 3d surface and unwrapping it onto the 2d uv register 
are so complex as to be only possibly in an automated way. This is what 
I understand by the term "auto unwrap".  Other strategies involve an 
automated first guess at what the flattened pattern might be, and then 
the tool supports further 'unwrapping' of the surface, by allowing the 
adjustment of the positions of the 3d vertices on the uv register, 
'manually'.  Either way this whole approach might viewed as bringing the 
3d information to the 2d information.


> In 3D painting, one paints the model through a 3D interactive view, just
> like one would do in real life. 

Which, as I picture it, is like unwrapping in reverse.  Again you are 
mapping from a 2d space to a 3d space but in this case the "2d" 
information, the pattern of the colours, is corresponded to the 3d 
information, the pattern of the vertices in space, through automated 
support of a manual process (painting).

So my question was, since I have never had any experience with such a 
tool first hand, does it indeed obviate any need for manually 
rearranging vertex mappings on a uv template, such as we get involved in 
when using uvmapper?  If so, it would seem to be a real productivity 
boost.  Basically I was just ooing and aweing.

-Jim

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