WorldPos in fragment shader goes from 0 to 1 instead real values

Graphics Shaders & Materials
1

Hi!

I’m going crazy… the wpos (worldPos) of this shader fors from 0 to 1 in the object, instead of showing the real world pos. Why is this? Thanks :slight_smile:

Shader "EffectBakers/FogBaker"
{
    Properties
    {
        [PerRendererData] _MainTex ("Color (RGB) Alpha (A)", 2D) = "black" {}
        [MaterialToggle] PixelSnap( "Pixel snap", Float) = 0
        [HideInInspector]_FogTexture( "Fog Ramp Texture", 2D) = "black" { }
        [HideInInspector]_01FogDepthVerticals( "Linear Depth 01 And Verticals", Vector) = (0.0, 0.0, 0.0, 0.0)    
        [HideInInspector]_IsCold( "Warm texture or Cold texture", Range(0,1)) = 0
    }

    SubShader
    {
        Tags { "Queue"="Transparent" "IgnoreProjector"="True" "RenderType"="Transparent" }
        Blend  SrcAlpha OneMinusSrcAlpha
    
        LOD 100
        ZWrite    Off
        Cull      Off
        Fog {Mode Off}

        Pass
        {
        CGPROGRAM
            #pragma vertex vert
            #pragma fragment frag
            #pragma target 3.0
            #pragma multi_compile _ PIXELSNAP_ON
            #include "UnityCG.cginc"
        
            struct appdata
            {
                float4 vertex   : POSITION;
                float2 texcoord : TEXCOORD0;
            };

            struct v2f
            {
                float4 vertex   : SV_POSITION;
                float2 uv_MainTex  : TEXCOORD0;
                half4  screenpos : TEXCOORD1;
                float3 wpos : TEXCOORD2;
            };
        
            fixed4 _Color;
            half4     _MainTex_ST;


            v2f vert(appdata v)
            {
                v2f o;
                o.vertex = mul(UNITY_MATRIX_MVP, v.vertex);            
                o.uv_MainTex = TRANSFORM_TEX(v.texcoord, _MainTex);
            
                #ifdef PIXELSNAP_ON
                o.vertex = UnityPixelSnap (o.vertex);
                #endif

                o.screenpos = ComputeScreenPos( o.vertex );
                o.wpos = mul(_Object2World, v.vertex);

                return o;
            }

            sampler2D _FogTexture;
            fixed4 _01FogDepthVerticals;
            int _IsCold;

            float4 FogColor(float2 worldPos)
            {
                float fog_bottom_column = 0.05 + ( _IsCold * 0.5);
                float fog_top_column = 0.15 + ( _IsCold * 0.5);

                float fog_depth = _01FogDepthVerticals.x;
                float front = ( abs( fog_depth ) - fog_depth ) / ( abs( fog_depth ) * 2 );

                fog_bottom_column += front * 0.2;
                fog_top_column += front * 0.2;
                fog_depth = abs(fog_depth);
            
                float2 fog_position_bottom = float2(fog_bottom_column, 1 - fog_depth);
                float4 bottom_FogTexture = tex2D(_FogTexture, fog_position_bottom);
            
                float2 fog_position_top = float2(fog_top_column, 1 - fog_depth);
                float4 top_FogTexture = tex2D(_FogTexture, fog_position_top);

                float vertical_pos = clamp((worldPos.y - _01FogDepthVerticals.y) / (_01FogDepthVerticals.z - _01FogDepthVerticals.y), 0, 1);

                return lerp(bottom_FogTexture, top_FogTexture, vertical_pos);
            }

            sampler2D _MainTex;

            fixed4 frag(v2f inp) : COLOR
            {
                fixed4 color = tex2D( _MainTex, inp.uv_MainTex );    
                fixed4 color_fog_tex = FogColor( inp.wpos );
                float color_factor = color_fog_tex.a;
                color_fog_tex.a = color.a;
                color = lerp( color, color_fog_tex, color_factor );
                color.rgb *= color.a;
                return inp.screenpos.y;
            }
        ENDCG
        }
    }
}

EDIT: This shader is used with a blit command, outisde run, to bake a texture. Is it possible that if the game is not running, I cannot know the position in the world?

EDIT2: The answer is yes :frowning:
So now I need help to know how to get the world position outside of runtime… Thanks!

EDIT3: Of course, blit doesn’t know about the object position because there is no object. I will open another thread asking that. This can be used for reference if someone finds same problem.

2

Same problem here!
I need to bake a shape calculated in screen space but the texture is then shrinked in a normalized [0 to 1] space…

Have you found a solution?