About Video Material

I want to clamp a video material to the terrain with slightly modifying the sandcastle example.As a result, the video material turns to be fragmented.
Is there a solution that can help me to clamp the video to the terrian or change the video transparency as a substitution?
It will be so grateful!!!!

Can you share a Sandcastle link that I can run, or a screenshot of the issue you’re seeing, and what you expect to see? I was able to put a video material on a polygon that’s clamped to ground. Here’s a Sandcastle of my attempt.

dear o, I seem to forget setting hierarchy instead of setting 2d. there is also a question , can you set the transparency of this polygon with a video material? I looked up the doc, and i could not find any option for that.
thx for replying me

I don’t think there’s a way to toggle that at the Entity level. You might need to create a custom Appearance and set it to be translucent: