我到哪里地上都有奇怪的黑影，为什么呢？
Where can I have a strange shadows on the ground, why?
watch?v=CrBaQSKIglw
How to Fix?
why?why?why?why?why?
pretty strange, is the light/shadow quality high?
How to adjust light/shadow quality?
You can read more about how to do that in the following documents.
Please let us know if you have any more questions.
I checked and found that settings are the highest, it seems not a quality problem
What kind of Video Card are you using? Also make sure that your video card drivers are up to date.
GTX 970,I updated the graphics driver, and now the problem is solved, thank you 
Awesome sauce, thanks for letting us and others know how you solved your problem.