How do you get a mask in the post process material? I have a blood texture which i want the background to be hidden and only show the blood drops? We can just use Opacity mask in a surface texture but what do we do with post process to do this?
Hey!
Shooter Game tutorial series have some very good explanation about damage indicator post process effects 
Take a look and follow what you see here!
Source: Player damage indicators and dying effect | Shooter Tutorial
Many thx AmphDev ill take a look at the link