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> I'm intrigued/puzzled/fascinated by your use of the image_map. How did you
> know where to place it in the first instance with a 'complicated' image,
> trial and error? Or is there a set way to determine this? I can guess that
> the large area of free-space around your logo is to cover the rest of the
> area on the mug, ie, the inside, outside of the mug, but why does it have
to
> be that way? Couldn't a smaller image be applied to one specific area of
the
> mug instead of having a large area of free-space? I don't understand this.

I guess I can answer this one since I modelled the mug in Rhino. The answer
is simple : it's a uv-mapped mesh. The bitmap template is obtained directly
using uvmapper (the original obj file is needed for that). It's large
because it covers the whole surface of the mug, interior and exterior (the
handle has its own map, not used here). Note that it could be very easy to
change the template and rewrite the mesh uv coordinates to give more space
to the logotype (again, using the original obj). One problem though is that
the uv grid lines are not parallel so that distortion occurs (tricky to
fix). See the attached screen shot of the mug in uvmapper pro (demo) showing
the repartition of the map surface.

Note that the logo could be done with a regular plane or cylinder mapping
after getting rid of the uv info, but then the image would get replicated on
the other side or in the inside and the normals would be messed up on the
edges. For simple objects like this, it's possible to find workarounds for
regular povray mapping, but uv mapping is much more flexible.


>    Also, can you explain why it's a reversed/mirror image before applying?

For some reason, there are problems of inversion with meshes and their uv
maps. Basically original (obj) mesh geometry tend to be inverted after
conversion to povray. This may be fixed during the conversion process, but I
tend to follow the easiest path...

G.


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