Lost Material.mainTexture if using AnimatableProperties.

[wallstudio]

Describe the bug
Lost Material.mainTexture if using AnimatableProperties.

To Reproduce
Steps to reproduce the behavior:

1. Create a ParticleSystem. (Default: mapped Circle texture)
2. Attach a UIParticle.
3. Enable any animatable properties. (not bind mainTexture).
4. See particle. Lost texture mapping.

Expected behavior
A Material that presented a canvas is inherit a texture of original material (that bind mainTexture).

Screenshots

Environment (please complete the following information):

• Version: v4.6.3
• Platform: Windows
• Unity version: 2023.2.7f1
• Build options: In Editor
• Project for reproducing: BugProject_UIParticle.zip

Additional context

// ModifiedMaterial class
// https://github.com/mob-sakai/ParticleEffectForUGUI/blob/6d8dee0/Runtime/ModifiedMaterial.cs#L28-L33
customMat = new Material(baseMat)
{
    name = $"{baseMat.name}_{id}",
    hideFlags = HideFlags.DontSave | HideFlags.NotEditable,
    mainTexture = texture ? texture : null
}

The UIParticle presents a copy material to a canvas, if enabled animatable properties. (at ModifiredMaterial class) That time, it uses UIParticleRenderer.mainTexture that is a atlas of TextureAnimationSheet. If it dose not have the TextureAnimationSheet, mainTexture is null. The material copying process is overrides mainTexture of the material after copy by Material constructor. So, it override mainTexture by null.

When Old version, NOP if the ParticleSystem dose not have a TextureAnimationSheet.

// Old ModifiedMaterial class
// https://github.com/mob-sakai/ParticleEffectForUGUI/blob/3.3.14/Scripts/ModifiedMaterial.cs#L28-L29
e.customMat = new Material(baseMat);
e.customMat.hideFlags = HideFlags.HideAndDontSave;
if (texture)
    e.customMat.mainTexture = texture;

I suggest revert this copy process.

[github-actions]

🎉 This issue has been resolved in version 4.6.4 🎉

The release is available on GitHub release

Your semantic-release bot 📦🚀

[github-actions]

🎉 This issue has been resolved in version 4.6.4 🎉

The release is available on GitHub release

Your semantic-release bot 📦🚀