probelm when use this component with SoftMask

[ltccss]

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Describe the bug
When there is a nested Particle, only one particle will be displayed if I make it softmaskable

To Reproduce
Steps to reproduce the behavior:
Here is the sample project
UIParticleTest.zip
When you open it, then

1. Open the SampleScene
2. Select the Particle System node ( the parent one), and play it

Expected behavior
Both 2 particle (red and white) should be displayed in the screen, and be clipped well

Screenshots
If applicable, add screenshots to help explain your problem.

Environment (please complete the following information):

• Platform: windows 7
• Unity version: 2018.4.21f1

[mob-sakai]

Yes.
SoftMask does not support multiple materials...

[ltccss]

I've seen....

In SoftMaskable, it releases the cached material at once when receive a new material during GetModifiedMaterialo((⊙﹏⊙))o.

The true problem may be it's hard to know if the cached material should be replaced or appended?

[mob-sakai]

NOTE: It may be supported by my new Mask package which will be released soon. :)