Well, i don't think you can, you'd need a variable to keep track of it, but if you do
rad=2
entityraduis sphere,rad
Then just create a sphere and scale it by the rad value.
Try this:
Graphics3D 800,600
SetBuffer BackBuffer()
camera=CreateCamera()
PositionEntity camera,0,0,-10
light=CreateLight()
s=CreateSphere()
radius=CreateSphere(8,s)
PositionEntity radius,0,0,0
EntityColor radius,50,50,180
EntityAlpha radius,0.5
rad#=1
s1=CreateSphere()
PositionEntity s1,5,0,0
EntityType s,1
EntityType s1,2
Collisions 1,2,1,1
While Not KeyHit(1)
If KeyDown(205) Then MoveEntity s,0.2,0,0
If KeyDown(203) Then MoveEntity s,-0.2,0,0
If KeyHit(200) Then
rad=rad+0.2
EntityRadius s,rad
ScaleEntity radius,rad,rad,rad
End If
If KeyHit(208) Then
rad=rad-0.2
EntityRadius s,rad
ScaleEntity radius,rad,rad,rad
End If
UpdateWorld
RenderWorld
Text 0,0," Press up and down to adjust collision radius. Left and right to move sphere"
Flip
Wend
End
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