Ok guys,
Thanks a lot for this very usefull Thread.
Starting from this, I went a little bit further with a case study (a waving flag shader).
Full documentation here :
http://klakos.com/en/advanced-waving-flag-shader-for-unity-double-sided-alpha-shadow-support-3/
It covers the following points :
-
- Flag vertices animation via a shader (trigo. way)
-
- Advanced ShaderLab surface shading for transparency management
-
- Adding a shadow Pass (with alpha support)
-
- Double-sided surfaces methods (methods 1, 2 and 3)
-
- Provided Double-sided Materials Configuration Wizard (for 3rd method)
Downloads [from the address bellow]
-
- PDF version of the article : WavingFlag.pdf
-
- Configuration Wizard : BackwardMaterialBuilder.cs
-
- Unity 3.3 Package : WavingFlagDemo.unitypackage | WavingFlagDemo.rar
Here is my shader code :
The “FlagWaveCG.cginc” file :
// Upgrade NOTE: replaced 'glstate.matrix.mvp' with 'UNITY_MATRIX_MVP'
// Original shader by cboe - Mar, 23, 2009
// Enhanced to 3 axis movement by Seon - Jan, 21, 2010
// Added _WaveSpeed by Eric5h5 - Jan, 26, 2010
// CHANGE LOG - Gauthier BOAGLIO (golgauth) / Klakos - May, 07, 2011 :
// - Added Transparency support
// - Added Spec and Normal mapping support
// - Added Shadow casting support (+ Shadow Alpha and Shadow Alpha cutoff support)
// [Done in the "ShadowCaster" additional Pass]
// - Added advanced double-sided rendering support
// - Added _WaveStrength param
//
// Requirements: assumes you are using a subdivided plane created with X (width) * Z (height) where Y is flat.
// Requirements: assumes UV as: left X (U0) is attatched to pole, and Top Z (V1) is at top of pole.
//
// [url]http://klakos.com/en/advanced-waving-flag-shader-for-unity-double-sided-alpha-shadow-support-3/[/url] ] for
// visuals and more informations
#include "UnityCG.cginc"
float4 _Color;
sampler2D _MainTex;
fixed _Cutoff;
float _WaveSpeed;
float _WaveStrength;
struct v2f {
V2F_SHADOW_CASTER;
float2 uv : TEXCOORD1;
};
void computeWave (inout appdata_full v, inout v2f o)
{
float sinOff=(v.vertex.x+v.vertex.y+v.vertex.z) * _WaveStrength;
float t=-_Time*_WaveSpeed;
float fx=v.texcoord.x;
float fy=v.texcoord.x*v.texcoord.y;
v.vertex.x+=sin(t*1.45+sinOff)*fx*0.5;
v.vertex.y=(sin(t*3.12+sinOff)*fx*0.5-fy*0.9);
v.vertex.z-=(sin(t*2.2+sinOff)*fx*0.2);
o.pos = mul( UNITY_MATRIX_MVP, v.vertex );
o.uv = v.texcoord;
}
The “FlagWave-Advanced.shader” file :
// Upgrade NOTE: replaced 'glstate.matrix.mvp' with 'UNITY_MATRIX_MVP'
// Original shader by cboe - Mar, 23, 2009
// Enhanced to 3 axis movement by Seon - Jan, 21, 2010
// Added _WaveSpeed by Eric5h5 - Jan, 26, 2010
// CHANGE LOG - Gauthier BOAGLIO (golgauth) / Klakos - May, 07, 2011 :
// - Added Transparency support
// - Added Spec and Normal mapping support
// - Added Shadow casting support (+ Shadow Alpha and Shadow Alpha cutoff support)
// [Done in the "ShadowCaster" additional Pass]
// - Added advanced double-sided rendering support
// - Added _WaveStrength param
//
// Requirements: assumes you are using a subdivided plane created with X (width) * Z (height) where Y is flat.
// Requirements: assumes UV as: left X (U0) is attatched to pole, and Top Z (V1) is at top of pole.
//
// See [ http://klakos.com/en/advanced-waving-flag-shader-for-unity-double-sided-alpha-shadow-support-3/ ] for
// visuals and more informations
Shader "Selfmade/for-2sided/FlagWave Advanced Regular"
{
Properties
{
// Ususal stuffs
_Color ("Main Color", Color) = (1,1,1,1)
_SpecColor ("Specular Color", Color) = (0.5, 0.5, 0.5, 0)
_Shininess ("Shininess", Range (0.01, 1)) = 0.078125
_MainTex ("Base (RGB) TransGloss (A)", 2D) = "white" {}
// Bump stuffs
//_Parallax ("Height", Range (0.005, 0.08)) = 0.02
_BumpMap ("Normalmap", 2D) = "bump" {}
//_ParallaxMap ("Heightmap (A)", 2D) = "black" {}
// Shadow Stuff
_Cutoff ("Shadow Alpha cutoff", Range(0.25,0.9)) = 1.0
// Flag Stuffs
_WaveSpeed ("Wave Speed", Range(0.0, 300.0)) = 50.0
_WaveStrength ("Wave Strength", Range(0.0, 5.0)) = 1.0
}
SubShader
{
Tags {
"Queue"="Geometry"
"IgnoreProjector"="True"
"RenderType"="Transparent"}
LOD 300
Pass
{
Name "ShadowCaster"
Tags { "LightMode" = "ShadowCaster" }
Fog {Mode Off}
ZWrite On ZTest Less Cull Off
Offset 1, 1
CGPROGRAM
// Upgrade NOTE: excluded shader from OpenGL ES 2.0 because it does not contain a surface program or both vertex and fragment programs.
#pragma exclude_renderers gles
#pragma vertex vert
#pragma fragment frag
#pragma fragmentoption ARB_precision_hint_fastest
#pragma multi_compile_shadowcaster
#include "FlagWaveCG.cginc"
v2f vert( appdata_full v )
{
v2f o;
computeWave(v, o);
TRANSFER_SHADOW_CASTER(o)
return o;
}
//sampler2D _MainTex;
float4 frag( v2f i ) : COLOR
{
fixed4 texcol = tex2D( _MainTex, i.uv );
clip( texcol.a - _Cutoff );
SHADOW_CASTER_FRAGMENT(i)
}
ENDCG
//SetTexture [_MainTex] {combine texture}
}
//CULL Front
CGPROGRAM
#pragma surface surf BlinnPhong alpha vertex:vert fullforwardshadows approxview
#include "FlagWaveCG.cginc"
half _Shininess;
sampler2D _BumpMap;
//sampler2D _ParallaxMap;
float _Parallax;
struct Input {
float2 uv_MainTex;
float2 uv_BumpMap;
//float3 viewDir;
};
v2f vert (inout appdata_full v) {
v2f o;
computeWave(v, o);
return o;
}
void surf (Input IN, inout SurfaceOutput o) {
// Comment the next 4 following lines to get a standard bumped rendering
// [Without Parallax usage, which can cause strange result on the back side of the plane]
/*half h = tex2D (_ParallaxMap, IN.uv_BumpMap).w;
float2 offset = ParallaxOffset (h, _Parallax, IN.viewDir);
IN.uv_MainTex += offset;
IN.uv_BumpMap += offset;*/
fixed4 tex = tex2D(_MainTex, IN.uv_MainTex);
o.Albedo = tex.rgb * _Color.rgb;
o.Gloss = tex.a;
o.Alpha = tex.a * _Color.a;
//clip(o.Alpha - _Cutoff);
o.Specular = _Shininess;
o.Normal = UnpackNormal(tex2D(_BumpMap, IN.uv_BumpMap));
}
ENDCG
}
Fallback "Transparent/VertexLit"
}
Hope this will help…
Maybe one of those new visual shader editors might be easier for me to work with…
