Does anyone know if the capability exists or has created a shader for velvet or satin? Specifically looking for effects to change with incidence angle to get the satin, velvet look. Thanks in advance.
Cheers,
Gary
I did experiment with cloth rendering some 4 years back. The easy and cheap trick in that time was to use a special cubemap to get satin/velvet-like look. I might dig up the cubemaps and the shaders somewhere (it was long time ago).
Thanks Aras. I hope to be able to do this in Unity. I use this capability often in software rendered scenery. I have seen some nVidia and DirectX shaders that do this.
Gary
Hi Gary.
You could use the X-Ray shader from the wiki as a start. It works like the Facing Ratio node in maya which can be used to create velvet → Maya Velvet shader tutorial. More info on the Facing Ratio shader node here.
/Patrik
Yes I thought about using that shader… I just don’t know enough yet about coding one. I will use that as a start since no one else has one created yet. Thanks for the tip.
Cheers,
Gary
Recreated the velvet effect from Steve J. Tubbrits maya tut by combining the X-Ray shader (wiki) + standard Self-Illumin/Diffuse + a little copying from the shader tuts in the docs.
Could be used for all kinds of rim-light effects aswell, just create a texture that fits your needs. Maybe a rimlight color can be added to control the look a bit more…
Shader "SC/Velvet" {
Properties {
_Color ("Main Color", Color) = (1,1,1,0.5)
_MainTex ("Base (RGB) Rim-Light Ramp (A)", 2D) = "white" {}
}
SubShader {
//make Self-Illumination depend on Facig Ratio
Pass {
Tags {"LightMode" = "PixelOrNone"}
Color [_PPLAmbient]
CGPROGRAM
// profiles arbfp1
// vertex vert
// fragment frag
// fragmentoption ARB_fog_exp2
#include "UnityCG.cginc"
float4 _Color;
sampler2D _MainTex : register(s0);
//sampler2D _BumpMap : register(s1);
struct v2f {
V2F_POS_FOG;
float2 uv : TEXCOORD0;
float2 uv1 : TEXCOORD1;
};
v2f vert (appdata_base v)
{
v2f o;
PositionFog( v.vertex, o.pos, o.fog );
o.uv = TRANSFORM_UV(0);
float3 viewDir = normalize(ObjSpaceViewDir(v.vertex));
o.uv1.x = dot(viewDir,v.normal);
o.uv1.y = 0.5;
return o;
}
half4 frag (v2f i) : COLOR
{
half4 texcol = tex2D( _MainTex, i.uv );
half4 texcol2 = tex2D( _MainTex, i.uv1 );
return texcol * _Color * texcol2.a;
}
ENDCG
SetTexture [_MainTex] {}
}
UsePass " Diffuse/PPL"
}
//FallBack "Self-Illumin/VertexLit", 1
FallBack "Normal-Diffuse", 1
}
Use a texture with a gradient alpha channel. See the attached file for an example.
34843–1274–$velvettexturepsd_188.zip (12.5 KB)
Looks awesome man, welldone!
AC
My friend I thank you soooo much! You should post it on the wiki now! Cannot thankyou enough!!! You are mighty!
Cheers,
Gary
That is so nice - now for a chance to earn some bonus points:
This shader can be easily converted to use texture combiners (instead of a fragment program) hence work on just about anything. Try to give it a shot for brownie points 
Challange accepted
I was a bit lazy when i did this I admit. Didn’t think about the best way, just copied pasted it together from other shaders. Could be a good exercise in texture combiners though!
/P
Got it working without the fragment program 
One thing I don’t get is how the different uv coordinates are used. Seems it automatically maps the first UV set to the first texture stage and the second UV set to the second texture stage? Is that right? I don’t need BindChannels to do that?
Shader "SC/Velvet" {
Properties {
_Color ("Main Color", Color) = (1,1,1,0.5)
_MainTex ("Base (RGB) Rim-Light Ramp (A)", 2D) = "white" {}
}
SubShader {
//For Velvet look, Make Self-Illumination Depend on Facig Ration
Pass {
Tags {"LightMode" = "PixelOrNone"}
Color [_PPLAmbient]
CGPROGRAM
// profiles arbfp1
// vertex vert
#include "UnityCG.cginc"
sampler2D _MainTex : register(s0);
struct v2f {
V2F_POS_FOG;
float2 uv : TEXCOORD0;
float2 uv1 : TEXCOORD1;
};
v2f vert (appdata_base v)
{
v2f o;
PositionFog( v.vertex, o.pos, o.fog );
o.uv = TRANSFORM_UV(0);
float3 viewDir = normalize(ObjSpaceViewDir(v.vertex));
o.uv1.x = dot(viewDir,v.normal);
o.uv1.y = 0.5;
return o;
}
ENDCG
SetTexture [_MainTex] {
constantColor [_Color]
combine constant * texture
}
SetTexture [_MainTex] {
constantColor (0,0,0,1)
combine previous lerp(texture) constant
}
}
UsePass " Diffuse/PPL"
}
FallBack "Normal-Diffuse", 1
}
That’s correct. BindChannels is only when you don’t use vertex programs; when you do you control what gets output to what yourself.
Thanks Aras. Things are beginning to make sense…
I’ll post it on the wiki.
/P
Shader is on the wiki → Velvet shader.
Also, did a little creative alpha channeling for a satin like look:
Simply AWESOME!!! Thank you so much for your efforts on this. I hope that I won’t be the only using this really cool shader!!!
Cheers,
Gary
i’ll definitly find a use for it too - that is a fantastic shader metervara - thanks for sharing ; )
Should be pretty nice for a silver-surfer-esque chrome look, too. 
Just playing around. I modeled a spider and put the Velvet
Shader on it. gives more like a painted metal effect.
Norby
35008–1279–$shader_fun_207.zip (3.18 MB)
I just don’t know enough yet about coding one. I will use that as a start since no one else has one created yet.
Creative spam?
3 semi-related replies, and what looks like an affiliate link for the website.
I apologize if this is not the case…
-Jeremy