Cant play FX with trail

[GardenG]

Describe the bug
Hi, I cant play correctly the VFX with trail.

Meteroite.zip

Expected behavior
The meteorite on the left is what I was expecting.

Screenshots

Environment (please complete the following information):

• Version [4.13.3]
• Platform: Editor(Windows)
• Unity version: [2022.3.62f1]

[mob-sakai]

Thanks for the report!

[mob-sakai]

Could you please provide a minimal reproduction project (not xxx.unitypackage) that includes the Assets, Packages, and ProjectSettings directories?
This would really help us investigate and resolve the issue.

No need to include any proprietary assets from your project - feel free to use placeholder or free assets instead.

[GardenG]

Thank you for the reply.
I just made a minimal project.

Project_MeteoriteVFX.zip

[mob-sakai]

Sorry for the late reply.
I checked Assets/Scenes/SampleScene.unity, but I couldn't figure out what your issue was...
I placed the included Assets/GameData/FX_UI_Meteorite.prefab in the scene without a UIParticle, but the "trail" you mentioned wasn't visible.
To be more precise, the trail’s geometry (mesh) is present, but it isn’t rendering due to a shader/material issue.
As a test, I assigned a simple UI/Additive shader to the trail's material, and the trail appeared; I got the same result with UIParticle as well.

[GardenG]

I think it's because you changed the shader. please use the shader I provided (UIBlend_UVMove_Noise), and you'll probably see that issue. That is a custom shader I created that supports the Mask component.
Maybe something wrong with this shader?

[mob-sakai]

A bug has been found in one of the shaders included in the project.
In the vert function of the Blend_UVMove_Noise shader, OUT.texcoord1 and OUT.texcoord2 are not being assigned values.
These values are used in the frag function for the uv_Mask and uv_Add calculations.

`user(TEXCOORD1)` mismatching vertex shader output type(s) or not written by vertex shader (null)

v2f vert(appdata_t v)
{
    v2f OUT;
    UNITY_SETUP_INSTANCE_ID(v);
    UNITY_INITIALIZE_VERTEX_OUTPUT_STEREO(OUT);
    OUT.worldPosition = v.vertex;
    OUT.vertex = UnityObjectToClipPos(OUT.worldPosition);
    OUT.texcoord = v.texcoord;
    OUT.color = v.color;
    return OUT;
}

[mob-sakai]

I was able to get it to display by adding the following to the vert function in Blend_UVMove_Noise shader.

OUT.texcoord.zw = float2(0.0, 0.0);
OUT.texcoord1 = float4(0.0, 0.0, 0.0, 0.0);
OUT.texcoord2 = float4(0.0, 0.0, 0.0, 0.0);

Also, by adjusting the drawing order, I can draw tw in the background.

[GardenG]

After modifying this change, it now works perfectly.
Thank you.