Texture Mapping an Opal

[Akash]

Hi
I began designing a pendant for a very nice Opal.
After building the [3dm] stone as accurately as possible [without scanning]
I used a picture of the actual stone for mapping
But…

After experimenting quite a lot with the [currently available] options for texture mapping in the Mac Rhino, the above screen-shot is the best i could come up with. It leaves un-mapped areas on the gemstone, strategically located for maximum visual disturbance while designing the setting.

1. is there a way to map the whole stone?

2. if there has to be a gap in the mapping… then is there a way to put the gap in the lower [horizontal] 3/4 of the stone as shown in the pic below?

here is the 3DM file:
FancyCooberPedyOpal.3dm (1.7 MB)
and this is the the top view picture of the opal [used here for the mapping]

with thanks
akash

[pascal (Pascal Golay)]

Hi Akash - setting Planar mapping on the stone should do it, I think, but this object is behaving a little strangely here with planar mapping - I’ll see if I can figure out what I’m forgetting…
Aha - delete the decal, just use a planar mapped material.

FancyCooberPedyOpal_PG.3dm (2.7 MB)
-Pascal

[Akash]

thank you very much Pascal
now with your suggestion the mapping cover the whole stone.
only thing is that i still get a stitch around the side.
it is workable as is, but perhaps there’s a way to have this stitch appear lower [somewhat below the griddle line] ?

with thanks
akash

[pascal (Pascal Golay)]

Hmm - that should not be, as far as I know… the planar map should be ‘mirrored’ seamlessly if the edge is smooth- I wonder of the underlying surface directions are flipped - does this one look any different on your machine?

FancyCooberPedyOpal_PG_UVFLip.3dm (3.1 MB)

-Pascal

[Akash]

yes it is seamless now
thank you very much

Then there is the next stage in order to make the stone more real looking, I’ll need to have also the picture of the back of the stone added. [different fire and pattern arrangement]
i seem to remember reading that i would have to wire-cut the Opal at the griddle, [to make 2 different materials]

or is there another way?

thank again
akash