Find if a point is in front of a face or behind a face

[Anonymous]

Hello,

My today's problem is that I am creating plugin which compares a wall and a point cloud. And i want to know if the point cloud point is in front of the face or behind the face. I Don't know if there is a tool which indicate the positon of a point compared to a face or a wall.  And if there is no tool if someone can help me find a mathematical way to determine if the point is in front of or behind the face.

I already compute the distance between the wall and the point cloud, the last thing that I have to do is to find if it is in front of or behind the face.

[jeremytammik · Accepted solution]

Search the Internet for something like 'signed distance point plane':

https://duckduckgo.com/?q=signed+distance+point+plane