Metal ?

[belly80naz]

Try to download some free metal shader from www.softimage.com and study it in the render tree. However to make good reflection for a metal shader you need a good image to reflect to it.:cool:

[belly80naz]

Sorry the more precise link: http://www.softimage.com/xsinet/Addon_display_abstract.asp?mode=compact&family=XLIB&catid=217&software=XSI&parent=25

[Atyss]

I have posted a couple of metal shaders here, one is gold:

http://www.xsibase.com/tools/shaders.php


Hope this helps
Salutations - Cheers
Bernard Lebel

[topmegacool]

Hi and thanks for the link,

I tryed your "metals" but I see nothing else than a basic material.
I missed what make them metalic ?

I was also desapointed by the metals from the xsi site.
the environment reflected by a metal should be colored by the diffuse color of the metal. When you loko at gold you see that all relfections and speculars (reflection of the light source) are tinted by the gold color.


The following picture show better what I mean.

the torus on the right are metal
the torus on the right are plastic

the 2 torus from the top of the picture are very reflective
the torus from the bottom have low reflection.

Well I feel a bit weird everywhere I ask, people answere "just activate the reflection".

[Atyss]

Well the thing is that with metal, reflection is pretty much about it: a good metal requires a great reflection map.

Metals generally have a dark diffuse color, although gold might be a little bit brighter (but never more than 0.5).

The reflectivity of all these materials on your picture is quite high, probably between 0.75 and 0.9. The thing is that the reflection map (most likely an HDRI map) provide good reflection color.

Note that there is a strong bump map that give the noisy texture. Noisy bumps break the reflection. You can also use glossiness to achieve a similar effect, though with gloss you'll get a more uniform blurred reflection.

Also note that the specular are quite important on these objects, and it is the last thing you should edit. Use a specular color that is above 1.0, between 1.0 and 3.0. Use a large specular area, avoid using Cook-Torrance. Phong and Blinn are perfect for these things.

You will notice that all the advices I just gave you match my shaders that you tried, the only difference is that in the image you posted there is bumpmapping and a larger specular.


Hope this helps
Salutations - Cheers
Bernard Lebel

[xsit]

my msn:mayaren@msn.com
:bounce:
http://www.chinavfx.com/bbs/attachments/200303/20034451-1.jpg

http://www.chinavfx.com/bbs/attachments/200303/20125937-1.jpg

http://www.chinavfx.com/bbs/attachments/200302/19090732-18204455-2.jpg

http://www.chinavfx.com/bbs/attachments/200302/19090830-18205702-5.jpg

[topmegacool]

hi,

Well these images you see aren't rendered with xsi.
and yes they are very high reflective.

Diffuse color of metals depend of the reflection and specular of it.
This is what I can't make in xsi, this relation is probably possible with al the possible nodes and connection but how ? that's the question. The other thing to consider is the reflection (including specular) must be tinted by the diffuse color of the metal, wich isn't the case for a plastic (for exemple).

You say a metal need a nice env pic, but then if you're in a 3d scene with raytrace reflections, how do you do since you can't choose the environement ?

- TMC

[topmegacool]

this was to answere to the Atyss post

sorry

[Atyss]

Originally posted by topmegacool
this was to answere to the Atyss post

sorry

You should try the DGS shader. You'll get it if you install the xphysics add-on that you'll find on XSI Net > Resources_> Shaders > Others. The exact name of the shader is xphysics_dgs, and is meant to be physically correct.


Cheers
Bernard

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