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"real 3d bouncing", by darkeagle

really really cool... just enable collisions with the world and any objects you want the ball to bounce with, and let this code do its stuff :) bouncy bouncy!

Code

Const col_world = 1
Const col_ball = 3
Collisions col_ball,col_world,2,2
Collisions col_ball,col_ball,1,2

Type ball
     Field entity
     Field xvel#,yvel#,zvel#
End Type

Const ball_gravity# = 0.05

For i = 1 To 10
     CreateBall(Rnd(-10,10),Rnd(-10,10),Rnd(-10,10),Rnd(-0.5,0.5),Rnd(-0.5,0.5),Rnd(-0.5,0.5))
Next

Function CreateBall.ball(x#=0,y#=0,z#=0,xvel#=0,yvel#=0,zvel#=0)

b.ball = New ball
b\entity = CreateSphere()
EntityColor b\entity,Rand(28,255),Rand(28,255),Rand(28,255)
EntityType b\entity,col_ball
PositionEntity b\entity,x,y,z
b\xvel# = xvel#
b\yvel# = yvel#
b\zvel# = zvel#
Return b

End Function

Function UpdateBalls(dt#=1)

For b.ball = Each ball

For i = 1 To CountCollisions(b\entity)
          HandleBallBounce(b,i)
     Next
     
     b\yvel = b\yvel - ball_gravity#
     
     TranslateEntity b\entity,b\xvel*dt,b\yvel*dt,b\zvel*dt
     
Next

End Function

Function HandleBallBounce(b.ball,i)

; Calculate bounce:

; Get the normal of the surface collided with. 
Nx# = CollisionNX#(b\entity, i) 
Ny# = CollisionNY#(b\entity, i) 
Nz# = CollisionNZ#(b\entity, i)

; Compute the dot product of the ball's motion vector and the normal of the surface collided with. 
VdotN# = b\xvel#*Nx# + b\yvel#*Ny# + b\zvel#*Nz#

; Calculate the normal force. 
NFx# = -2.0 * Nx# * VdotN# 
NFy# = -2.0 * Ny# * VdotN# 
NFz# = -2.0 * Nz# * VdotN#

; Add the normal force to the motion vector. 
b\xvel#=(b\xvel# + NFx#)
b\yvel#=(b\yvel# + NFy#)
b\zvel#=(b\zvel# + NFz#)

End Function

Code software created by Krylar's Kreations