Unity - 2D圆孔与抗混叠的对象

Question

我想在一个空物体里面添加一个洞，里面有精灵。这个洞是圆形的。

为了实现这一点，我在材质中添加了一个着色器，并在空对象中添加了一个Sprite Renderer组件。

这是我的着色器:

Shader "Sprite/Hole Effect"
{
Properties
{
_MainTex ("Base (RGB)", 2D) = "white" {}
_ObjPos ("Object Position", Vector) = (1,1,1,1)
_Cutoff ("Alpha cutoff", Range(0,1)) = 0.5
_Radius ("Hole Radius", Range(0.1,10)) = 2
}

SubShader
{
Pass
{
Cull Off

CGPROGRAM

#pragma vertex vert
#pragma fragment frag

uniform sampler2D _MainTex;
float _Radius;
float4 _ObjPos;

struct vertexInput {
float4 vertex : POSITION;
float4 texcoord : TEXCOORD0;
};
struct vertexOutput {
float4 pos : SV_POSITION;
float4 worldPos : POSITION1;
float4 tex : TEXCOORD0;
};

vertexOutput vert(vertexInput input)
{
vertexOutput output;

output.tex = input.texcoord;
output.pos = UnityObjectToClipPos(input.vertex);
output.worldPos = mul(input.vertex, unity_ObjectToWorld);
return output;
}

float4 frag(vertexOutput input) : COLOR
{
float4 textureColor = tex2D(_MainTex, input.tex.xy);
float dis = distance(input.worldPos.xyz, _ObjPos);

if (dis > _Radius)
{
discard;
}

return textureColor;
}

ENDCG
}
}

FallBack "Diffuse"
}

这个方法的问题是没有圆的抗锯齿…

所以我试着给空对象添加一个精灵蒙版，但是也没有抗锯齿…

我认为着色器是很好的解决方案来实现，但真的不知道如何!

任何帮助都是完美的!!

Answer 1

终于找到了!!

我在我想要看到圆的物体的精灵上应用了一个带有着色器的材质。

这是我的着色器:

Shader "Sprites/XRay Effect"
{
Properties
{
[PerRendererData] _MainTex ("Sprite Texture", 2D) = "white" {}

_PlayerPos ("Player Position", Vector) = (0,0,0,0)
_Radius ("Hole Radius", Range(0.1,100)) = 2
_Border ("Border", Range(0.001,1)) = 0.05
}
SubShader
{
Tags
{ 
"Queue"="Transparent" 
"IgnoreProjector"="True" 
"RenderType"="Transparent" 
"PreviewType"="Plane"
"CanUseSpriteAtlas"="True"
}

Cull Off
Lighting Off
ZWrite Off
ZTest [unity_GUIZTestMode]
Blend SrcAlpha OneMinusSrcAlpha
Pass
{
CGPROGRAM
#pragma vertex vert
#pragma fragment frag
#include "UnityCG.cginc"
#include "UnityUI.cginc"

struct vertexInput
{
float4 vertex   : POSITION;
float4 color    : COLOR;
float2 texCoord : TEXCOORD0;
};
struct vertexOutput
{
float4 vertex   : SV_POSITION;
fixed4 color    : COLOR;
half2 texCoord  : TEXCOORD0;
float3 worldPosition : TEXCOORD1;
};

sampler2D _MainTex;

float4 _PlayerPos;
float _Radius;
float _Border;
vertexOutput vert(vertexInput IN)
{
vertexOutput OUT;
OUT.vertex = UnityObjectToClipPos(IN.vertex);
OUT.texCoord = IN.texCoord;
OUT.worldPosition = mul(unity_ObjectToWorld, IN.vertex);
OUT.color = IN.color;
return OUT;
}
fixed4 frag(vertexOutput IN) : SV_Target
{
half4 color = tex2D(_MainTex, IN.texCoord) * IN.color;

// Adding the circle hole
float dis = distance(IN.worldPosition.xyz, _PlayerPos.xyz);
color.a = lerp(0, color.a, color.a * (dis - _Radius) / _Border);
return color;
}

ENDCG
}
}
FallBack "UI/Default"
}

您可以根据您的需要修改lerp(0, color.a, color.a * (dis - _Radius) / _Border)部分。