Optimizing spherical mask shader for mobile - unity3d

Question

I have used a shader that is very heavy for mobile performance. Can someone help me to improve it in order to get better performance?
I have noticed that my FPS with this shader goes from 60 to 30.
Shader "Custom/Sphered2"
{Properties
{
[HDR] _Color ("Color", Color) = (1,1,1,1)
_MainTex ("Albedo (RGB)", 2D) = "white" {}
_ColorStrength("Color Strenth", Range(1,4)) = 1
_EmissionColor ("_EmissionColor Color", Color) = (1,1,1,1)
_EmissionTex ("_EmissionColor (RGB)", 2D) = "white" {}
_EmissionStrength("_EmissionColor Strenth", Range(0,4)) = 1
_Glossiness ("Smoothness", Range(0,1)) = 0.5
_Metallic ("Metallic", Range(0,1)) = 0.0
// _position ("World Position", Vector) = (0,0,0,0)
// _Radius ("Sphere Radius", Range(0,100)) = 0
//_Softness("Sphere Softness", Range(0,100)) = 0
}
SubShader
{
Tags { "RenderType"="Opaque" }
LOD 200
CGPROGRAM
// Physically based Standard lighting model, and enable shadows on all light types
#pragma surface surf Standard fullforwardshadows
// Use shader model 3.0 target, to get nicer looking lighting
#pragma target 3.0
sampler2D _MainTex,_EmissionTex;
struct Input
{
float2 uv_MainTex;
float2 uv_EmissionTex;
float3 worldPos;
};
half _Glossiness;
half _Metallic;
fixed4 _Color,_EmissionColor;
half _ColorStrength,_EmissionStrength;
uniform float4 GLOBALmask_position2;
uniform half GLOBALmask_Radius2;
uniform half GLOBALmask_Softness;
// Add instancing support for this shader. You need to check 'Enable Instancing' on materials that use the shader.
// See https://docs.unity3d.com/Manual/GPUInstancing.html for more information about instancing.
// #pragma instancing_options assumeuniformscaling
UNITY_INSTANCING_BUFFER_START(Props)
// put more per-instance properties here
UNITY_INSTANCING_BUFFER_END(Props)
void surf (Input IN, inout SurfaceOutputStandard o)
{
// Albedo comes from a texture tinted by color
fixed4 c = tex2D (_MainTex, IN.uv_MainTex) * _Color;
half grayscale = (c.r + c.g + c.b) * 0.333;
fixed3 cgg = fixed3(grayscale,grayscale,grayscale);
fixed4 e = tex2D (_EmissionTex, IN.uv_EmissionTex) * _EmissionColor *_EmissionStrength;
half d = distance(GLOBALmask_position2,IN.worldPos);
half sum = saturate((d - GLOBALmask_Radius2)/ -GLOBALmask_Softness);
fixed4 lerpColor = lerp(fixed4(cgg,1),c * _ColorStrength,sum);
fixed4 lerpEmission = lerp(fixed4(0,0,0,0),e,sum);
o.Albedo =c.rgb;
// Metallic and smoothness come from slider variables
o.Metallic = _Metallic;
o.Emission = lerpEmission.rgb;
o.Smoothness = _Glossiness;
o.Alpha = c.a;
}
ENDCG
}
FallBack "Diffuse"
}
I have used it like this :
using System.Collections;
using System.Collections.Generic;
using UnityEngine;
public class RayCastMovePos : MonoBehaviour
{
public Transform playerTransform;
public float radius2,sm;
public Vector4 myPos2;
void Update()
{
myPos2= new Vector4 ( playerTransform.position.x ,
playerTransform.position.y, playerTransform.position.z, 0);
//radius =Mathf .Clamp ( ( myVisualizer.allRythem
[0]+myVisualizer.allRythem [1]+myVisualizer.allRythem [2]) * 170,2,1000);
// radius2 =Mathf .Clamp ( ( myVisualizer.allRythem
[3]+myVisualizer.allRythem [4]+myVisualizer.allRythem [5]) * 150,2,1000);
Shader.SetGlobalVector ("GLOBALmask_position2", myPos2);
Shader.SetGlobalFloat ("GLOBALmask_Radius2", radius2);
Shader.SetGlobalFloat ("GLOBALmask_Softness", sm );
}
}
I am new to shaders, but if there are any suggestions for glowing a sprite, I would be glad to hear it.

Answer 1

If this is for a sprite, then do you really need to use a surface shader? These include tons of overhead, like lightmapping support, shadow casting/receiving, forward light support, etc. I'm sure a vertex/fragment shader would work fine for your purposes. You get emission by simply adding extra color to the final output.
Here is how the body of Unity's sprite shader looks:
https://github.com/TwoTailsGames/Unity-Built-in-Shaders/blob/master/CGIncludes/UnitySprites.cginc