Error using custom vertex streams (5.6)

Unity Engine
1

Hi all, I want to test out custom vertex streams for particles.

I have a particle system with Render Mode set to Mesh.
I have these set the particle system custom streams:

Position (POSITION.xyz)
Normal (NORMAL.xyz)
Color (COLOR.xyzw)
UV (TEXCOORD0.xy)
Center (TEXCOORD0.zw|w)
Velocity (TEXCOORD1.yzw)

And this in my shader:

...
struct appdata
            {
                float4 vertex : POSITION;
                float3 normal : NORMAL;
                fixed4 color : COLOR;
                float4 texcoord : TEXCOORD0;
                float4 texcoord1 : TEXCOORD1;
            };

            struct v2f
            {
                float4 vertex : SV_POSITION;
                fixed4 color : COLOR;
                float4 texcoord : TEXCOORD0;
                float4 texcoord1 : TEXCOORD1;
            };
...

My problem is the particle system is saying TEXCOORD streams do not match. What am I doing wrong?
If I remove Center and Velocity the error goes away.

2

Fixed it. I wasn’t setting v2f.texcoord1 in my vertex shader. The error wasn’t very helpful though.

3

I meet the same error.
Why must v2f.texcoord1 be set in your vertex shader? because the texcoord1 is only an input steamData.

4

I’m also having this issue. Not sure what I’m doing wrong.

5 
            struct appdata
            {
                float4 vertex : POSITION;
                float4 uv : TEXCOORD0;
                float2 mask_uv : TEXCOORD1;
                fixed4 color : COLOR;
            };

            struct v2f
            {
                float4 uv : TEXCOORD0;
                float2 mask_uv : TEXCOORD1;
                UNITY_FOG_COORDS(1)
                float4 vertex : SV_POSITION;
                fixed4 color : COLOR;
            };

            v2f vert (appdata v)
            {
                v2f o;
                o.vertex = UnityObjectToClipPos(v.vertex);
                o.uv.xy = TRANSFORM_TEX(v.uv.xy, _MainTex);
                o.mask_uv = TRANSFORM_TEX(v.mask_uv, _MaskTex);
                UNITY_TRANSFER_FOG(o,o.vertex);
                o.color = v.color;
                return o;
            }
           
            fixed4 frag (v2f i) : SV_Target
            {
                _PrimaryST.z = fmod((_Time.x * 3) + i.uv.z, 1);
                float2 primaryUV;
                primaryUV.x = i.uv.x * _PrimaryST.x + _PrimaryST.z;
                primaryUV.y = i.uv.y * _PrimaryST.y + _PrimaryST.w;
                fixed4 col1 = tex2D(_MainTex, primaryUV);

                _SecondaryST.z = fmod((_Time.x * 2) + i.uv.z, 1);
                float2 secondaryUV;
                secondaryUV.x = i.uv.x * _SecondaryST.x + _SecondaryST.z;
                secondaryUV.y = i.uv.y * _SecondaryST.y + _SecondaryST.w;
                fixed4 col2 = tex2D(_MainTex, secondaryUV);

                fixed4 maskCol = tex2D(_MaskTex, i.mask_uv);
                // apply fog
                UNITY_APPLY_FOG(i.fogCoord, col);
               
                return (col1.a * col2.a * maskCol.a) * i.color * _Color + pow(col1.a * col2.a * maskCol.a * _AddAmount, _AddPow);
            }

3506739--279779--Screen Shot 2018-05-22 at 8.58.30 PM.png

6

From the documentation and your error I can see that your custom vertex stream data is also packed into texcoord0 by Unity.
Inside your appdata struct however you are defining a secondary texcoord1 - this might be the cause of the error. Your mask_uv variable is not needed as long as your uv variable (texcoord0) has components to store the additional vertex stream data (packed into the z component).

Edit:
After thinking some more about it the mask_uv variable might stay. The culprit lies elsewhere.
I believe it is related to your code setting only uv.xy inside the vertex shader. You are not writing the z value to the output.

7

Did this ever get solved? I am having the same issue now.

8

i’m also getting this error with using unity shader “Particles/Standard Unlit” using default particle system without any touch. it’s wierd.

1 Like