Here you go :)
Uses the function from the above mentioned code archive:
;How to predict if two entities will collide, not taking their speed into consideration
;By Jeppe Nielsen 2004
;Lines_intersect function by sswift
; Values returned by the Lines_Intersect() function.
Global Intersection_X#
Global Intersection_Y#
Global Intersection_AB#
Global Intersection_CD#
Graphics3D 800,600,16,2
SeedRnd MilliSecs()
cam=CreateCamera()
PositionEntity cam,0,400,0
RotateEntity cam,90,0,0
CameraZoom cam,5
Global ent1=CreateCube() : EntityFX ent1,1
Global ent2=CreateCube() : EntityFX ent2,1
Global intersectsphere=CreateSphere()
EntityColor intersectsphere,255,255,0
EntityFX intersectsphere,1
HideEntity intersectsphere
PositionEntity ent1,20,0,10
RotateEntity ent1,0,45,0
PositionEntity ent2,0,0,-20
RotateEntity ent2,0,0,0
Repeat
MoveEntity ent1,0,0,0.1
MoveEntity ent2,0,0,0.1
If KeyHit(57)
resetentities
EndIf
RenderWorld
Text 400,10,"Space to reset entities",1
Text 400,20,"Flashing yellow sphere indicates intersection point",1
If CollisionCourse(ent1,ent2)
Text 400,300,"ENTITIES ARE ON A COLLISION COURSE!",1,1
If Sin(MilliSecs()*5)>0
ShowEntity intersectsphere
Else
HideEntity intersectsphere
EndIf
PositionEntity intersectsphere,Intersection_X#,0,Intersection_Y#
Else
HideEntity intersectsphere
EndIf
Flip
Until KeyDown(1)
End
Function resetentities()
PositionEntity ent1,Rnd(-20,20),0,Rnd(-20,20)
RotateEntity ent1,0,Rnd(360),0
PositionEntity ent2,Rnd(-20,20),0,Rnd(-20,20)
RotateEntity ent2,0,Rnd(360),0
End Function
Function CollisionCourse(e1,e2)
x1#=EntityX(e1,1)
z1#=EntityZ(e1,1)
TFormVector 0,0,1,e1,0
dx1#=TFormedX()
dz1#=TFormedZ()
x2#=EntityX(e2,1)
z2#=EntityZ(e2,1)
TFormVector 0,0,1,e2,0
dx2#=TFormedX()
dz2#=TFormedZ()
;if trajectories are parallel
If Lines_Intersect(x1,z1,x1+dx1,z1+dz1,x2,z2,x2+dx2,z2+dz2)=False
Return False
Else
Return Intersection_AB#>=0 And Intersection_CD#>=0
EndIf
End Function
;function by sswift
Function Lines_Intersect(Ax#, Ay#, Bx#, By#, Cx#, Cy#, Dx#, Dy#)
Rn# = (Ay#-Cy#)*(Dx#-Cx#) - (Ax#-Cx#)*(Dy#-Cy#)
Rd# = (Bx#-Ax#)*(Dy#-Cy#) - (By#-Ay#)*(Dx#-Cx#)
If Rd# = 0
; Lines are parralel.
; If Rn# is also 0 then lines are coincident. All points intersect.
; Otherwise, there is no intersection point.
Return False
Else
; The lines intersect at some point. Calculate the intersection point.
Sn# = (Ay#-Cy#)*(Bx#-Ax#) - (Ax#-Cx#)*(By#-Ay#)
Intersection_AB# = Rn# / Rd#
Intersection_CD# = Sn# / Rd#
Intersection_X# = Ax# + Intersection_AB#*(Bx#-Ax#)
Intersection_Y# = Ay# + Intersection_AB#*(By#-Ay#)
Return True
EndIf
End Function
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