Double Vision (Unity 5.0):
根据 http://http.developer.nvidia.com/CgTutorial/cg_tutorial_chapter03.html 教程来编写的Unity5.0 Shader。
基本思路是将Texture的UV向左和向右各自横移一小段距离得到两个新的UV(TexCoordLeft和TexCoordRight),
然后根据这两个UV将Texture取样出两个颜色值、Color1和Color2,然后将两个颜色值平等的Blend在一起。
Shader代码如下:
Shader "Unlit/DoubleVision"
{
Properties
{
_MainTex ("Texture", 2D) = "white" {}
_LeftOffset("Left Offset", Range(-1, 0)) = -0.1
_RightOffset("Right Offset", Range(0, 1)) = 0.1
}
SubShader
{
Tags { "RenderType"="Opaque" }
LOD 100
Pass
{
CGPROGRAM
#pragma vertex vert
#pragma fragment frag
#include "UnityCG.cginc"
struct appdata
{
float4 vertex : POSITION;
float2 uv : TEXCOORD0;
};
struct v2f
{
float2 uv : TEXCOORD0;
UNITY_FOG_COORDS(1)
float4 vertex : SV_POSITION;
};
sampler2D _MainTex;
float4 _MainTex_ST;
float _LeftOffset;
float _RightOffset;
v2f vert (appdata v)
{
v2f o;
o.vertex = mul(UNITY_MATRIX_MVP, v.vertex);
o.uv = TRANSFORM_TEX(v.uv, _MainTex);
return o;
}
fixed4 frag (v2f i) : SV_Target
{
// sample the texture
float2 leftTexCoord = i.uv + float2(_LeftOffset, 0);
float2 rightTexCoord = i.uv + float2(_RightOffset, 0);
fixed4 col_l = tex2D(_MainTex, leftTexCoord);
fixed4 col_r = tex2D(_MainTex, rightTexCoord);
fixed4 col = lerp(col_l, col_r, 0.5);
return col;
}
ENDCG
}
}
}
输入的图片:
经Shader处理后的输出: