Getting proper rebound...

Blitz3D Forums/Blitz3D Programming/Getting proper rebound...

OrcSlayer

(Posted 2006) [#1]

Ok, when I'm trying to do some simple, quasi-physics, my main problem comes from getting the correct rebound angle from collisions. To explain, if I use collision normals to align a projectile to a collision, I get this result:

What I want to do is have a proper rebound angle, like this:

But I'm honestly not sure how to get the results in a way that would be proper regardless of where the impact takes place. Does anyone have any ideas how to quickly and easily do this?

To those who have played Unreal/Unreal Tournament, look at it like this: Razorjack/Ripper disks bouncing off walls.

Stevie G

(Posted 2006) [#2]

Try this ...

For C = 1 To CountCollisions( Entity )
	Nx# = CollisionNX( Entity, C )
	Ny# = CollisionNY( Entity, C )
	Nz# = CollisionNZ( Entity, C )
	VdotN# = Vx * Nx + Vy * Ny + Vz * Nz
	NFx# = -2.0 * Nx * VdotN
	NFy# = -2.0 * Ny * VdotN
	NFz# = -2.0 * Nz * VdotN
	Vx = Vx + Nfx
	Vy = Vy + Nfy
	Vz = Vz + Nfz
Next
AlignToVector Entity, Vx, Vy , Vz ,  3, 1

Where Vx, Vy and Vz are your velocity vector. Remember to make them floats.

Stevie

OrcSlayer

(Posted 2006) [#3]

Thanks! Will try that out ASAP.