How to find the angle of incidence of a projectile hit
I am currently using a physical projectile system and I want to only ricochet (bounce) projectiles when the angle between the surface normal and the projectile vector is above a certain value. Example: I've looked through several answers on how to achieve this but none of them seem to give me expected results. Based on this answer, here is what my BP graph currently looks like for calculating the angle of incidence:
However this is giving me unexpected results. When at a more glancing angle, I seem to get a believable angle value (111 degrees) as seen from this image: However when I am more head on with the object, the angle gets larger! I know that the correct answer to this question is for me to get better at vector math, however hopefully someone can point me in the right direction so that I can achieve what I am looking for here. Thanks.
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I believe I have fixed this by subtracting the arccos angle from 180.
Thank you. I've been trying to figure out how to do this for a while. I've added to it for my own needs so I can get a chance out of 100 that the bullet will ricochet. The greater the angle the better the chance it will ricochet.
With this I'm getting a range from 0 (straight on) to 90 on both sides. How do I know if i'm hitting it from the left or the right? If I'm coming from the left side of the object or the right side of the object to hit in the same spot