uGUI Transition Shader

Transition.shader

Shader "UI/Cunstom/transition"
{
	Properties
	{
		// Set from "source image" in Image component.
		[HideInInspector]_MainTex ("Texture", 2D) = "white" {}
		_Edge ("Edge", Range(0, 1)) = 0.01
		_Progress ("Progress", Range(0, 1)) = 0
	}
	SubShader
	{
		Tags { "RenderType"="Transparent" "Queue" = "Transparent" }
		LOD 100

		Pass
		{
			Blend SrcAlpha OneMinusSrcAlpha

			CGPROGRAM
			#pragma vertex vert
			#pragma fragment frag

			#include "UnityCG.cginc"

			struct appdata
			{
				float4 vertex : POSITION;
				float4 color : COLOR;
				float2 uv : TEXCOORD0;
			};

			struct v2f
			{
				float2 uv : TEXCOORD0;
				fixed4 color : COLOR;
				float4 vertex : SV_POSITION;
			};

			sampler2D _MainTex;
			fixed _Edge;
			fixed _Progress;

			v2f vert (appdata v)
			{
				v2f o;
				o.vertex = UnityObjectToClipPos(v.vertex);
				o.uv = v.uv;
				o.color = v.color;

				return o;
			}

			fixed4 frag (v2f i) : SV_Target
			{
				fixed4 col = tex2D(_MainTex, i.uv);
				fixed alpha = smoothstep(_Progress - _Edge, _Progress, 1 - col.rgb);

				col.rgb = i.color;
				col.a = i.color.a * alpha;
				return col;
			}
			ENDCG
		}
	}
}