Is there a way to make hair fall to the ground as if cut with scissors?

Hello!

Imagine you have a a character with hair, and that hair is being cut by a barber. The hair would fall to the ground in the locations where the scissor blades cut.

If you made the hair ordinary particles instead, particles fall to the ground uniformally - how do you make them only fall to the ground where touched by another object?

Ideas welcome! Thanks!

Perhaps dynamic pain can activate gravity on particles?

I have used a texture within the particle system so that the gravity only effects particles within that texture’s white space. It almost works perfectly. The only problem is that some particles fall slower than others, and they are the ones that are on parts of the texture where white borders onto black. SO, I thought this was because of of antialiasing between black and white. So I went back to photoshop and posterised the texture so that all pixels are either 100% black or 100% white (no greys), and yet the slow gravity on pixels that borders between black and white still occur. I can only think this is because Blender is antialiasing the texture internally. Any advice please?

I have used Dynamic Paint to solve the main problem. A frame sequence derived from Dynamic Paint to select which particles fall under gravity, and which do not.

I tried to upload an animated gif to show this, but it says that file type is not allowed here (even though ‘.gif’ is!?).

Some particles remain slow because of what i mentioned above:

The only problem is that some particles fall slower than others, and they are the ones that are on parts of the texture where white borders onto black. SO, I thought this was because of of antialiasing between black and white. So I went back to photoshop and posterised the texture so that all pixels are either 100% black or 100% white (no greys), and yet the slow gravity on pixels that borders between black and white still occur. I can only think this is because Blender is antialiasing the texture internally.