Displacement Maps

[alexx]

fairly easy answer: use mental ray :)

but for maya.. quite easy as well:
create your shader and surface and then just connect the map you wanna have as displacement to the shading groups displcement input of your shading group (SG) (that thing that comes even before your lambert or blin shader)..

connection is by default the alpha channel.. if you want it different do it with the connection editor.

to adjust the displace height, change the alpha gain (or color gain for a non default connection as mentioned).

now you have to go to the surface and tweak the settings for theadaptive desplacement (in attribute editor). higher values mean better results and loniger rendertimes and higher mem usage..

but i would really suggest using mental ray for that task..
with its adaptive displacement values you get perfect results (even when displacing a single poly with a checker board which maya simply cant)..
and mem usage is way lower than with maya renderer

hope i could help

cheers

alexx

[Jason-Kane]

I have been working with them for some time and have not yet been able to get as good of results with them as I am able to get from Renderman.

I am using 16 bit per channel images and attempting to get really complex detailed displacements out of them. What I am getting instead is very mushy and blobby. It is not picking up the fine detail. I tried shifting the Alpha Gain and then rendering it on spatial with fine detail but the render time went through the roof. Does anyone have any specific tips on the various types of displacements and what they mean. More importantly which one picks up the most detail and quality.

Thanks All.


KANE:beer:

[galactor]

When using Maya's displacement shader, it is hard to get large displacements, so use images with a low contrast. It also take very long to calculate (compared to MAX).

:: Galactor ::

[artistx]

Jason Kane. I believe the reason you're getting the mushy effect is because your mesh isn't dense enough. If my memory serves correctly, Maya's native displacements only work on base geometry, not micropolygons. In Mental Ray and Renderman compliant renderers the mesh is diced (chopped) into a bunch of tiny tiny polygons called micropolygons. The micropolygons are then displaced. ( a very general summary- please read Advanced Renderman for details). That's why the MR and renderman renderings tend to look nicer. The displacement is on a finer scale. I think Vray and Brazil for 3ds max also have this feature as well. In my opinion, I've found good renderman renderers like PRman, BMRT, and AIR to render detailed displacements faster than MR and dense mesh Maya/Max renders. I think MR handles displacements a little differently...

[Peter Reynolds]

If you do use the maya render and the displacement makes your object look like it has increased in volume, use a negative number in the Alpha Offset to correct it.

[onlooker]

http://dolinsky.fa.indiana.edu/caveart/fall01/show/nshipley/disp.html


http://www.seanomlor.com/mikeb/



http://www.drone.org/



http://home.pacific.net.au/~phourmouzis/research.htm


http://www.soclab.bth.se/practice.html


:)

[DeathBrain]

There are lots of tweak adjustment/parameter settings with solid looking Displacement Maps, ie :

1. Number of uv patches (if nurbs), number of faces (if poly)
2. Image Mipmap settings
- gaussian filter type with pre-filter radius (blur set)
3. Global Render :
- Multipixel filtering

Here's nurbs with UV patches 1x1
http://www.geocities.com/zigaretos/jooey_render_fault.txt

And here's nurbs with UV patches 20x20 (zzollid & zzmoottthh eh)
http://www.geocities.com/zigaretos/jooey_render.txt

And it is also important to keep in-out gradient alpha smoothness clean (without any noise or dirt at all), this not only for text displacement, but also for another displacement maps such as crumpy textures etc.
http://www.geocities.com/zigaretos/smoothness.txt

Download sample here (http://www.geocities.com/zigaretos/displace_sample.zip) (right click - save as)
(Shader Network included) - Maya 4.0 format - standard render :blush:

Anyway, this is simple (text) displacement, but it also works with complex detailed displacements, if dealing with complex detailed displacements, then we should use high-res alpha images and also lots of uv patches or faces. But i suggest to use MR for more softness (even Maya standard render works well)

Edit : sorry for those nickname jooey, this was sample for him

[Dark Alchemist]

UGH, I hate geoshities because the links are almost always DOA 99% of the time (and I really wanted that file to learn from).

[DeathBrain]

sample zip download doesnt work ? :eek:
arghh...yeah... what tha geoshities..:thumbsdow
send me your email to my message :)

[DeathBrain]

Ok has been sent to your E-Mail

Here's another example, i used 2048x2048 tga file applied to nurbs cylinder (32x32 patches) with glass displacement, it works well (standard render)..
Oh yeah...i like it better than use Max's displacement
Anyway just dont use small resolution for displacement map...
More bigger, more softness, and more sweeet :beer:

ok i hope that helps :)

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