bump mapping in difusse material

[Scog]

I suspect some other rendering engines may have some special optimisations to accentuate bumps in this kind of situation. The way I understand bump maps work I would expect exactly the kind of results that octane has shown.
Maybe they have some sort of internal normal map generator, or maybe their diffuse materials do not follow the same formula as that in octane.
Whatever the reason, I do think that bump maps could be made more effective in octane, but I don't think there is anything broken in the current code.
For now though, I think we would do well using glossy materials in place of diffuse where appropriate, after all, few if any materials in reality are truly 100% diffuse.

[radiance]

Hi,

I explained the reason very clearly, it's because the amount of bump mapping is capped at a maximum.
It depends on the scale of your object and if you're object is too large you won't see the effect.

if you take a piece of wood 1x1cm you will see bumps right ?
now if you look at a piece of 1x1km of the same wood from a kilometer away will you still see the bumps ? no.

i capped (eg maximum) our bump map depth amount so people can work in the right scale with a decent amount of bump.
once you don't have the right scale of your model anymore, eg the model is too large, you can't increase it as it's capped.

The reason it's capped is that otherwise most new users will use the default and have horrible bump mapping artifacts (when using a correct scale)

Radiance

[andrian]

Examples : Bump and Normal mapping in maxwell render 2.0

This is what we expect.. according my tests with Vray and 3dsmax Scanline, it's clear that Octane diffuse bump not working as the other engines I tested.. with the same sized objects..

Now some bump mapping testing.
I get crash every time when I try to import normal maps in octane.. It seems solution its simple, pause the renderer and load the normal map, then start it again..
I tried to test bump and normal mapping in other renderers ( vray mostly ). As I get a crash ,I didn't made the normal map test (lost the scene).
I also include the render from nVidia direct3D normal mapping.
Here is a quick chart I just made:

[cjd2]

Well, then, conclusion:
Everything is O.K. ... or not ?
You may say that the issue is finished and there is nothing more to clarify or amend, no? .
If not, please comment .
In my view, I do not feel satisfied .
Thanks again to everyone for working on this post, interesting things are always removed when several people give their opinion .
Radiance Thanks for the time and the explanations you have provided .
Bye.
Cjd2

[Chris]

Examples : Bump and Normal mapping in maxwell render 2.0

normal.jp

bump in maxwell.jp

This is what we expect.. according my tests with Vray and 3dsmax Scanline, it's clear that Octane diffuse bump not working as the other engines I tested.. with the same sized objects..

Now some bump mapping testing.
I get crash every time when I try to import normal maps in octane.. It seems solution its simple, pause the renderer and load the normal map, then start it again..
I tried to test bump and normal mapping in other renderers ( vray mostly ). As I get a crash ,I didn't made the normal map test (lost the scene).
I also include the render from nVidia direct3D normal mapping.
Here is a quick chart I just made:

bump test.jp

You cant compare it to biased and scanline engines, they work in a total different way. You cant really compare it to maxwell either, why? Because maxwell have mesh emitters wich means a focused light source, wich again will give the best bump mapping results. Look at the maxwell images, they have light sources coming from sharp angles also. Wait until Octane has mesh emitters before you complain

And one more thing, in your "render tests" why dont you show the wall from the exact same camera angle? That DO makes a difference, images you rendered with octane have a much sharper angle then the rest of the images, wich makes the bump effect look less visible. The scanline renders looks like shit also right from that angle?

[andrian]

And one more thing, in your "render tests" why dont you show the wall from the exact same camera angle? That DO makes a difference, images you rendered with octane have a much sharper angle then the rest of the images, wich makes the bump effect look less visible. The scanline renders looks like shit also right from that angle?

See, the first image of vray and the first and second of octane renders ( diffuse and glossy with dark blue background) have the same camera angles, exported to octane with max2octane script... all lit with sun light. Rest of Vray renders are just to show how bump values reflects over surface..

As for the maxwell render, I making the test with sun light so it will ignore the limitation of light emitter source issue you talking about, then we will talk again...
The test will follow with Fry render as well...
Scanline test was just to show different render engine, as I don't have maxwell or fry at home..
Mentalray image is coming too..
Iray will follow..

I make comparison, its nothing to do with complains..

DIFFUSE Bump map in octane render it's not working as other render engines I test...

PS: Scene is lit with sun light and exporter (max2octane) placed the sun in right direction, just you can't see bump in Octane ( diffuse materials - in glossy materials it's visible ) coz its not working like Vray for example, and according my new tests with fry and maxwell seem that even unbiased engines, renders this exactly as vray does.. lots of bump.. simulate depth using bump map... lit with sun light...
I will post images later tonight.

If you read carefully you will see that I didn't typed that bump its not working at all... just not as the other engines and like other artist are use to see and expect...

[vinz]

thanks andrian for taking the time to do this nice comparison, imo it speak by itself..

[radiance]

i can remove the limit but then everyone new will get bumps of meters and such and constantly post problematic images.

Radiance

[vinz]

why don't give the choice to the user as an option that we can activate or desactivate ?

[andrian]

If artist know what is doing, why limit the tool ??
If someone can't use it right , so its time to learn it, no? With better documents about it, all will learn with time...