My shader doesn't work if I use the same material for multiple objects with the same texture.

Hey, everyone!

I am very new to shaders and I tried making a billboard shader. I used the code from this video

The shader works fine if there is only one object with a material from this shader. It stays in the same position and looks at the camera as the camera rotates , it is the effect I wanted. But:

• If I create another object with the same sprite and the same material, in certain camera angles sprites get rendered at very far positions out of the cameras view range.

• If I create another object with the same sprite and use another material I created from this shader, It also works fine.

• I tried using material property block and used that for different objects with the same sprite and the same material, it only works if the property values different from each other, if they are the same it doesn't work either.

• I am using Sprite renderer, when I tried using mesh renderer it didn't have this problem and worked fine, but I want to use Sprite renderer and really wondering what is the issue here?

• Also the sprites I am using has transparent parts, but I am not sure it has anything to do with this problem. I come across this thread about alpha blended tree billboards and I am not sure if it is a " alpha blended materials don't sort properly problem"

Any help greatly appreciated.

Here is the shader code :

  Shader "Shaders/UnlitBillBoard"
 {
 Properties
 {
     _MainTex ("Texture", 2D) = "white" {}
     
     [PerRendererData]_ScaleFactor("Scale Factor" , Range(0,1)) = 0

     [PerRendererData]_ReferenceDistance("Referance Distance", Float) = 10
 }
 SubShader
 {
     Tags { "RenderType"="Transparent" "Queue" = "Transparent+500" }
     LOD 100

     Pass
     {
         ZTest Off
         Blend SrcAlpha OneMinusSrcAlpha
         Cull Off

         CGPROGRAM
         #pragma vertex vert
         #pragma fragment frag
         // make fog work
         #pragma multi_compile_fog

         #include "UnityCG.cginc"

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

         struct v2f
         {
             float2 uv : TEXCOORD0;
             UNITY_FOG_COORDS(1)
             float4 vertex : SV_POSITION;
         };

         sampler2D _MainTex;
         float4 _MainTex_ST;
         float _ScaleFactor;
         float _ReferenceDistance;

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

             float4 world_origin = mul(UNITY_MATRIX_M ,float4(0,0,0,1));
             float4 view_origin = float4(UnityObjectToViewPos(float3(0,0,0)),1);

             float scale = (_ScaleFactor * (length(view_origin) / _ReferenceDistance)) + ((1 - _ScaleFactor));

             float4 world_pos = mul(UNITY_MATRIX_M , float4(scale,scale,scale,1) *  v.vertex); 
             float4 flipped_world_pos= float4(-1,1,-1,1) * world_pos - world_origin + view_origin;
             //float4 view_pos = mul(UNITY_MATRIX_V,world_pos);
             float4 view_pos = world_pos - world_origin + view_origin;
             float4 clip_pos = mul(UNITY_MATRIX_P,view_pos);


             o.vertex = clip_pos;
             o.uv = TRANSFORM_TEX(v.uv, _MainTex);
             UNITY_TRANSFER_FOG(o,o.vertex);
             return o;
         }

         fixed4 frag (v2f i) : SV_Target
         {
             // sample the texture
             fixed4 col = tex2D(_MainTex, i.uv);
             // apply fog
             UNITY_APPLY_FOG(i.fogCoord, col);
             return col;
         }
         ENDCG
     }
 }

}