Mental Ray - Shaders

#801

Wow, that’s actually pretty cool! I’ve been dong some grass tests in PFlow but that turns out way to slow, I think it looks pretty cool!

#802

Hi there,

small update before going to party :beer:

thx deetee…slow/fast is always a matter of the project hehehe…

anyways did a second test with the same material without masking the grass and without length variations…

The direction is variating, but hardly seen in this rendering…best seen by the repeating patterns of light and shadow :cry:

Anyways, Sampling and minimum length for the displacement would have to be adjusted for better quality in production i assume. This render took almost 7 mins, but it has a hell lot of grass strands lol

Thorsten

#803

I also have to create grass. Can you explain the procedure? And send the grass material files?

regards, rohit

#804

This old grass material was created during the first few months release of Max6 and I have been meaning to optimize this but somehow never had the time. So I’m hoping you guys could help me out.

Its an MR displacement which takes so long to render.

And, if anyone is interested, how can I upload the files?

#805

@jucarojin : i assume we are basically using the same techniques. How long is “so long to render” in that frame you posted ?

@rohit : i´ll up the files as soon as am “satisfied” with the results :rolleyes:
The procedure is rather simple:

Max standard material
Use a noise in diffuse slot to create colour variance (two green/brownish tones)
Use a 3d-Displacement in the mental ray displacement extension slot
use a speckle as extrusion map
use whatever map you want in extrusion lenght slot to vary the length of the strands.

use any map in the direction slot to control the bending of strands if wanted /needed at all

That´s it…you´ll have to lower the minimum displacement length in the render settings to get it render properly…i used 0,5 un my renders

Hope that helps as a start,

Thorsten

#806

jucarojin: Anyone that has any helping contribution can upload their material to the designated MR uploarder locatedHERE :slight_smile:

#807

sorry for the delay guys - had a hectic end of week/weekend.

The ocean shader and scene is now on the uploader under the name of "Rich_Joyce_Ocean_Scene.rar "

if anybody can manage to transfer this material onto other projects, keeping the same look to it, i’d like to know how :slight_smile:

cheers,
Rich

#808

Just incase you guys didn’t know this already, you can use RGB colors to define the direction of the displacement.

Blue = Z Axis
Green = Y Axis
Red = X Axis

Naturally, just place the desired color in the direction map slot of the 3D displacement parameters map. I’m thinking you could texture map an object and use these colors to “paint” the needed displacement onto the object?

#809

@folical :

You cOULD paint the directions, however i assume that´s a rather tedious task. The best solution would be painting onto the different chanels in PS i´d guess. Cause determining the mix colours for the 3 directions would be rather hard i think.

Another thing i am unsure of is how to do negative X or Y values…my grass only bended in one direction. Would i have to set the base direction to negative and use grey to get direction changing in both directions ??

#810

guys from the mental ray shader mailing list said that the best way to change the vectors of the extrusion level is by nesting extrusion maps via the shader list.

I havent exactly tried this though.

The grass posted above used 3 bitmaps mapped in the MIX and NOISE material in the Displacement slot of Mental Ray shader.

#811

Can I create a rainbow effect from my caustics using the modified diffraction plugin? if so how do i accomplish this - i’ve used it in XSI but not in max and it doesnt seem to have the same slot to go in. also - which is the best material type for it?

thanks for any replies in advance

#812

Hello rich joyce

I downloaded "Rich_Joyce_Ocean_Scene.rar " but cloudy_noon.jpg file is missing. Can u post that too?

regards, rohit

#813

its the environment map. just to make the sky look nice :slight_smile: use anything it has nothing to do with the shader

#814

Is the rendering information get stored somewhere? I mean time taken in rendering most importantly (if one missed to see it during the render).

thanks, rohit

#815

hi rich joyce,

how to make it loop?

regards, rohit

#816

Rohit - yes bottom left of your screen, next to the pink and white command boxes.

Rohit - yes you can make it loop. the two animation parameters are in the ocean shaders - you can set the number of frames it loops over, and you also can control the wavelength and phase of the wave modifier.

#817

Originally posted by Rich Joyce
Rohit - yes you can make it loop. the two animation parameters are in the ocean shaders - you can set the number of frames it loops over, and you also can control the wavelength and phase of the wave modifier.

I already adjusted ocean shader parameters

but making a perfect loop using wave modifier phase etc. settings is a bit difficult & i can’t try different settings & see the result because of long rendering times.

I still have to find the right wavelength & phase settings to make it loop.

thanks anyway!
rohit

#818

you can always render in a preview mode… the wave modifier is a geometry displacement so will show up.

alternatively, get rid of the wave modifier and see what the results are without it

#819

Hi All,

Has anyone tried to tackle velvet or refractive/reflective anistropic shaders (like the ones on brushed metal that reverse direction from the center to form 2 “V” shaped highlights, with or without prism like colors) with MR.
Also wondering about peach fuzz…anyone?
It might be nice to work on before we actually Need them.

Zom
:wink:

#820

Hi Rich,

I’ve been using the diffraction shader and I was also interested in trying to produce the dispersion (prismatic rainbow) effect in the output caustics. Unfortunately, to my knowledge, nothing exists (at least publicly available) that does that. Daniel Rind (who wrote the fixed Diffraction shader) told me that he is working on a photon output shader that is intended to accomplish this but it is not completed and I haven’t heard from him regarding a projected date yet. This was within the past week so I’m not counting on anything too soon. (I’ll never pressure anyone with programming skills who’s creating anything that I’d like!)

If you look on page 52 of this thread, you can see the link to the crystal effect that I’ve been working on to this effect.

If you find anything before me, tell me, and I’ll do likewise.

bobg