Problems using Transparency map, reflection layer, and bump map at the same time

[jackm]

Good morning all.

I have a puzzle for you:

I'm attempting to render a platinum necklace with laser engraving on the back in Rhino using V-Ray. I have a platinum texture which I am using which uses a reflection layer with a fresnel map with an IOR of 20. Colour for the platinum comes from the filter on the reflection layer. I'm using a second surface for the decal, which uses the same texture as a basis, but I've added several things:

• reduced glossiness on the reflection layer (for the laser engraved effect)
• a full transparency under diffuse
• a transparency bitmap in the shape of my engraving under diffuse transparency
• a bumpmap using an inverted version of my engraving (I've tried it with and without alpha, but it makes no difference.)

The effect should be that the platinum object has a razor thin surface floating just on top of it with a bump map.

The problem is that the transparency is not cutting out the shape like its supposed to.

Here is an image as an example.



To be clear, that raised square surrounding the engraving shape should not be there.

Can anyone help?

Regards,

Jack

[dalomar_cg]

Re: Problems using Transparency map, reflection layer, and bump map at the same time

I think I'll need some more information to be able to say exactly what's going on. I'm following you, but I'm just not able to visualize exactly how you have things setup. If you could post a screen cap of the material and the map that you're using that would be very helpful.

[jackm]

Re: Problems using Transparency map, reflection layer, and bump map at the same time

Dear Dalomar:

No Problem. You can download the .3dm file and associated texture maps here:

http://www.h3-d.com/downloads/transparency_problem.3dm
http://www.h3-d.com/downloads/dog_ta...ansparency.jpg
http://www.h3-d.com/downloads/dog_tag_back.jpg


I'm using Rhino's basic StudioD.hdr for the background, but I don't think that would make a difference on this.

[dalomar_cg]

Re: Problems using Transparency map, reflection layer, and bump map at the same time

Thanks for the images and scene...is this the result that you were looking for??



All I did was "flipped" the maps for the alpha and bump, so that alpha was using the black on white version and bump as using the white on black version.

[jackm]

Re: Problems using Transparency map, reflection layer, and bump map at the same time

Thank you for the fast response.

I'm sorry to say, but no. In your image, the bump map for the engraving is outset. I need it inset. If this were laser-engraved, then the shape would be carved into the background by only a tiny shallow distance.


Regards,

Jack