Initial commit: Unity WordConnect project

Assets/WordConnectGameToolkit/Materials/Shaders/SpriteHole.shader

@@ -0,0 +1,73 @@
+Shader "Custom/SpriteHole"
+{
+    Properties
+    {
+        _MainTex ("Sprite Texture", 2D) = "white" {}
+        _Radius ("Hole Radius", Float) = 0.3
+        _EdgeSharpness ("Edge Sharpness", Float) = 200
+    }
+    SubShader
+    {
+        Tags 
+        { 
+            "Queue"="Transparent" 
+            "RenderType"="Transparent" 
+            "PreviewType"="Plane"
+        }
+
+        Cull Off
+        Lighting Off
+        ZWrite Off
+        Blend SrcAlpha OneMinusSrcAlpha
+
+        Pass
+        {
+            CGPROGRAM
+            #pragma vertex vert
+            #pragma fragment frag
+            #include "UnityCG.cginc"
+
+            struct appdata_t
+            {
+                float4 vertex   : POSITION;
+                float4 color    : COLOR;
+                float2 texcoord : TEXCOORD0;
+            };
+
+            struct v2f
+            {
+                float4 vertex   : SV_POSITION;
+                fixed4 color    : COLOR;
+                float2 texcoord : TEXCOORD0;
+            };
+
+            sampler2D _MainTex;
+            float4 _MainTex_ST;
+            float2 _HoleCenter;
+            float _Radius;
+            float _EdgeSharpness;
+
+            v2f vert(appdata_t IN)
+            {
+                v2f OUT;
+                OUT.vertex = UnityObjectToClipPos(IN.vertex);
+                OUT.texcoord = TRANSFORM_TEX(IN.texcoord, _MainTex);
+                OUT.color = IN.color;
+                return OUT;
+            }
+
+            fixed4 frag(v2f IN) : SV_Target
+            {
+                fixed4 c = tex2D(_MainTex, IN.texcoord) * IN.color;
+                float2 center = float2(0.5, 0.5); 
+                float dist = distance(IN.texcoord, center);
+                float circle = saturate((dist - _Radius) * _EdgeSharpness);
+                
+                c.a *= circle;
+                
+                return c;
+            }
+            ENDCG
+        }
+    }
+}