Bump depth

This sounds too easy but I have spent quite a bit of time on it.
How do you control the depth of the bump map?
Also I am trying to have (a very simple simulation of) a mosaic surface, and when I use the 2d or 3d checker structure it will reflect a small edge surface ad infinitum.
On top of that, the bump map effect is pretty bad even when compared with the spherical preview on the material settings.

any help welcomed

Can you post a 3dm file and any textures it uses in any materials or environments? Also, what rendering plugin are you using or is this straight Rhino Render? Please post any images of references that you are trying to match as well and I’ll take a look.

Hi Brian,
Thanks for your reply. I’ll try to prepare some screenshots and file (I wanted to replicate from scratch anyway).
In the meantime, do you have any tip on how to control the bump depth?
thanks, N

The rendering plugin you are using would dictate what material settings are available to you and where they live. I’m still not sure if you are using a plugin. In general, bump is based on the black and white values of the texture used and the lighting in the scene as it relates to the surfaces with the bump. You might just need to adjust your lighting and or the rotation of an environment HDR.

test.3dm (47.3 KB)
So attached a very simple example. A vertical surface 250 x 500 mm, and two horizontal surfaces at top and bottom end, 5 mm deep, 5 mm away from the edge. no plugins, just rhino render
The vertical surface has a bump map 2d checker texture default from Rhino, in this case a repeat of 40 x 20 to achive the rough size of a mosaic tile.
Originally I did not have any lighting, the scenes below have skylight (just because it highlights the reflection better.
here is the result

with a frontal view

note that the horizontal surfaces are reflected da infinitum

zooming the “bump depth” looks pixelated bars that do not scale regarding the repeat numbers (and therefore with a high repeat number become almost as big as the texture). and do not vary with the grayscale value.
here with black and white chedkers

here with white and light grey

here with black and dark grey

here with 20x10 repeat

How to control the bump depth (no plug-in)?
How to improve the quality?
How to avoid the infinity reflection?

Thanks, N

There a few things here to think about in order to make the bump more bumpy. The first is the texture used. If the black to white transition is a hard line the bump is less noticed and doesn’t look as deep as when there is a grayscale ramp between the black and white. In the attached file I used the Rhino Resample texture to blur the checker texture. The next thing to think about is the lighting and this includes the environment. I used one of the default environments with Rhino which can be found in the Libraries panel. There are a few that have High Dynamic Range textures in them which make bump mapping more intense. Simply drag and drop it to some empty space in any view to load the environment into the scene. Then look at the Environments panel to edit it if needed. I also added a rectangular light to the scene. The last thing to think about is the geometry the bump is on and how that geometry is oriented in relation to other objects and the world space itself. It’s a lot like photographing a bumpy material except you never have an all gray room with no other objects and where you are invisible with the camera. Hopefully this makes some sense and helps a little. Here’s a video on materials and environments in Rhino 5 for Windows as well …

test_bjames.3dm (5.3 MB)

Hi Brian,
Thanks for that.
I don’t really want it more bumpy. I know in other programs you can control the depth and I thought it would be a pretty obvious thing to have.
Actually I was relatively satisfied with the bumping mosaic from a distance what made me look closer was that infinite reflection and that I still did not understand… and is important because my design has the mosaic framed and it looks like there is a plane on the other side of the mirror. I have placed to spheres on close to the surface and one intersecting it a bit and you see that this one is also reflected to the infinite.

Any ideas about that?

on the bump itself, as I said from a distance it does the job (I am not looking for realism but just a quick illustration, but look closely and it looks like the image is simply repeated twice forming a weird grid.

here I am actually using a grey scale image of a single mosaic tile.

Not great effect and no control over it (inverting the image colours gives similar results).

but as I said the really disturbing thing is the reflection until the infinite. Thanks fo your help.

I think that reflection might be correct if the material is perfectly reflective. Scuffing up the material should help but since Rhino Render in v5 doesn’t support that in the basic material definition, I opted for blurring the source bump image. I also added planar mapping so the tiling can be controlled outside of the material. That mapping may also be better for you versus leaving it as the default surface UV. If this still isn’t to your liking, I’d suggest trying one of the available rendering plugins for Rhino.

Checker texture…

Mosaic tile…

test2_bjames.3dm (269.5 KB)

Thanks, Brian.
I am trying now to play with v-ray (which I used to know very lightly from a previous life).
However, the material editor keeps crashing. I don’t know if it is because of the evaluation, but it does get a high evaluation as it stands.
Any recommendations?

Thanks, N