如何在Scrollview中剔除Unity着色器颜色渐变材质

Question

我有一个制作颜色渐变的着色器，我将其应用于滚动视图中的子对象的图像组件。当超出滚动视图的边界时，此材质不会被剔除。子对象的所有其他部分都会被适当地剔除，只是材质梯度不会被剔除。

如何编辑我在网上找到的这个着色器脚本，以便在越界时剔除材质？

Shader "Custom/SpriteGradient" {
Properties{
[PerRendererData] _MainTex("Sprite Texture", 2D) = "white" {}
_Color("Left Color", Color) = (1,1,1,1)
_Color2("Right Color", Color) = (1,1,1,1)
_Scale("Scale", Float) = 1
// these six unused properties are required when a shader
// is used in the UI system, or you get a warning.
// look to UI-Default.shader to see these.
_StencilComp("Stencil Comparison", Float) = 8
_Stencil("Stencil ID", Float) = 0
_StencilOp("Stencil Operation", Float) = 0
_StencilWriteMask("Stencil Write Mask", Float) = 255
_StencilReadMask("Stencil Read Mask", Float) = 255
_ColorMask("Color Mask", Float) = 15
// see for example
// http://answers.unity3d.com/questions/980924/ui-mask-with-shader.html
}
SubShader{
Tags {"Queue" = "Background"  "IgnoreProjector" = "True"}
LOD 100
ZWrite On
Pass {
CGPROGRAM
#pragma vertex vert  
#pragma fragment frag
#include "UnityCG.cginc"
fixed4 _Color;
fixed4 _Color2;
fixed  _Scale;
struct v2f {
float4 pos : SV_POSITION;
fixed4 col : COLOR;
};
v2f vert(appdata_full v)
{
v2f o;
o.pos = UnityObjectToClipPos(v.vertex);
o.col = lerp(_Color,_Color2, v.texcoord.x);
//            o.col = half4( v.vertex.y, 0, 0, 1);
return o;
}

float4 frag(v2f i) : COLOR {
float4 c = i.col;
c.a = 1;
return c;
}
ENDCG
}
}
}

Answer 1

Shader "Custom/SpriteGradient" {
Properties{
[PerRendererData] _MainTex("Sprite Texture", 2D) = "white" {}
_Color("Left Color", Color) = (1,1,1,1)
_Color2("Right Color", Color) = (1,1,1,1)
_Scale("Scale", Float) = 1
// these six unused properties are required when a shader
// is used in the UI system, or you get a warning.
// look to UI-Default.shader to see these.
_StencilComp("Stencil Comparison", Float) = 8
_Stencil("Stencil ID", Float) = 0
_StencilOp("Stencil Operation", Float) = 0
_StencilWriteMask("Stencil Write Mask", Float) = 255
_StencilReadMask("Stencil Read Mask", Float) = 255
_ColorMask("Color Mask", Float) = 15
// see for example
// http://answers.unity3d.com/questions/980924/ui-mask-with-shader.html
}
SubShader{
Tags {"Queue" = "Background"  "IgnoreProjector" = "True"}
LOD 100
ZWrite On
Stencil
{
Ref [_Stencil]
Comp [_StencilComp]
Pass [_StencilOp] 
ReadMask [_StencilReadMask]
WriteMask [_StencilWriteMask]
}
ColorMask [_ColorMask]
Pass {
CGPROGRAM
#pragma vertex vert  
#pragma fragment frag
#include "UnityCG.cginc"
fixed4 _Color;
fixed4 _Color2;
fixed  _Scale;
struct v2f {
float4 pos : SV_POSITION;
fixed4 col : COLOR;
};
v2f vert(appdata_full v)
{
v2f o;
o.pos = UnityObjectToClipPos(v.vertex);
o.col = lerp(_Color,_Color2, v.texcoord.x);
//            o.col = half4( v.vertex.y, 0, 0, 1);
return o;
}

float4 frag(v2f i) : COLOR {
float4 c = i.col;
c.a = 1;
return c;
}
ENDCG
}
}
}