unity-shader-Unity3D的着色器介绍（四）——vertex and fragment shader实例

原文链接：http://liweizhaolili.lofter.com/post/1cc70144_6635a9f

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顶点片段着色器是最标准和通用的着色器类型，能实现的效果也是最丰富的，以下是几个比较常见的例子：

1、显示颜色和一张贴图

Shader "Example/VFBase" {
Properties {
_MainTex("Base(RGB)",2D) = "white"{}
_Color("MainColor(RGB)",Color) = (1,1,1,1)
}
SubShader {
Pass
{
CGPROGRAM
#pragma vertex vert
#pragma fragment frag
#include "UnityCG.cginc"
float4 _Color;
sampler2D  _MainTex;
float4 _MainTex_ST;
struct v2f {
float4  pos : SV_POSITION;
float2 uv : TEXCOORD0;
} ;
v2f vert (appdata_base v)
{
v2f o;
o.pos = mul(UNITY_MATRIX_MVP,v.vertex);
o.uv = TRANSFORM_TEX(v.texcoord,_MainTex);
return o;
}
float4 frag (v2f i) : COLOR
{
float4 texCol = tex2D(_MainTex,i.uv);
float4 outp = _Color*texCol;
return outp; 
}
ENDCG
}
} 
FallBack "Diffuse"
}

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2、随着时间动画的条状切割效果，透明叠加+双面显示

可以调整切割的数量、间隔和每条的宽度，从下往上动画

Shader "Example/VFClip" {
Properties {
_MainTex("Base(RGB)",2D) = "white"{}
_Color("MainColor(RGB)",Color) = (1,1,1,1)
_Speed("Speed(1-100)",Range(1,100)) = 10
_Sum("Sum(1-100)",Range(1,100)) = 20
_Space("Space(0.1-5)",Range(0.1,5)) = 1
_Width("Width(0.1-1)",Range(0.1,1))=0.5
}
SubShader {
Blend One One
AlphaTest Greater 0.5
Cull off
Pass
{
CGPROGRAM
#pragma vertex vert
#pragma fragment frag
#include "UnityCG.cginc"
float4 _Color;
float _Speed;
float _Sum;
float _Space;
float _Width;
sampler2D  _MainTex;
float4 _MainTex_ST;
struct v2f {
float4  pos : SV_POSITION;
float2 uv : TEXCOORD0;
float4 scrPos;
} ;
v2f vert (appdata_base v)
{
v2f o;
o.pos = mul(UNITY_MATRIX_MVP,v.vertex);
o.uv = TRANSFORM_TEX(v.texcoord,_MainTex);
o.scrPos = v.vertex;
return o;
}
float4 frag (v2f i) : COLOR
{
float2 wcoord = (i.scrPos.yz/i.scrPos.w);
float4 outp;
float l = Time*Speed;
if (abs(fmod(Sum*wcoord.x-l,Space))<_Width) {
float4 texCol = tex2D(_MainTex,i.uv);
outp = _Color*texCol;
}
else
{
outp = (0,0,0,0);
}
return outp; 
}
ENDCG
}
} 
FallBack "Diffuse"
}

---

3、反色效果

Shader "Example/VFInverse " {
Properties {
_MainTex("Base(RGB)",2D) = "white"{}
_Color("MainColor(RGB)",Color) = (1,1,1,1)
_Inv("Ref",Range(0,1)) = 1
}
SubShader {
//Blend One One
AlphaTest Greater 0.5
Cull off
Pass
{
CGPROGRAM
#pragma vertex vert
#pragma fragment frag
#include "UnityCG.cginc"
float4 _Color;
float _Speed;
float _Inv;
sampler2D  _MainTex;
float4 _MainTex_ST;
struct v2f {
float4  pos : SV_POSITION;
float2 uv : TEXCOORD0;
} ;
v2f vert (appdata_base v)
{
v2f o;
o.pos = mul(UNITY_MATRIX_MVP,v.vertex);
o.uv = TRANSFORM_TEX(v.texcoord,_MainTex);
return o;
}
float4 frag (v2f i) : COLOR
{
float4 outp;
float4 texCol = tex2D(_MainTex,i.uv);
float4 newCol = (1-texCol.r,1-texCol.g,1-texCol.b,texCol.a);
outp = abs(Inv-texCol)*Color;
outp.a = texCol.a;
return outp; 
}
ENDCG
}
} 
FallBack "Diffuse"
}

---

4、遮挡X光透视效果

Shader "Example/XRaySimple" {
Properties {
_MainTex ("Base (RGB)", 2D) = "white" {}
_Color("MainColor(RGB)",Color) = (1,1,1,1)
_RimColor("RimColor",Color) = (1,1,0,1)
}
SubShader {
LOD 200
Pass
{
Blend SrcAlpha OneMinusSrcAlpha
ZTest Greater
ZWrite Off
Lighting off
CGPROGRAM
#pragma vertex vert
#pragma fragment frag
#include "UnityCG.cginc"
float4 _RimColor;
struct v2f {
float4  pos : SV_POSITION;
float3 color:COLOR;
} ;
v2f vert (appdata_base v)
{
v2f o;
o.pos = mul(UNITY_MATRIX_MVP,v.vertex);
   float3 viewDir = normalize(ObjSpaceViewDir(v.vertex));
                    float dotProduct = 1 - dot(v.normal, viewDir);
                    float rimWidth = 0.7;
o.color.rgb = smoothstep(1 - rimWidth, 1.0, dotProduct);
                    o.color *= _RimColor;
return o;
}
float4 frag (v2f i) : COLOR
{
float4 outp;
outp.rgb = i.color+i.color;
outp.a = i.color;
return outp; 
}
ENDCG
}
Pass
{
ZTest Less
Lighting On
Blend SrcAlpha OneMinusSrcAlpha
Material
{
Diffuse [_Color]
}
SetTexture[_MainTex]
{
Combine texture * primary DOUBLE
}
}
} 
FallBack "Diffuse"
}