Point3 along a ray ?

[djlane]

Probably do it with vectors like so:


magnatude = 35
nodea = $Point01

nodeB = $Point02

nodeC = $Point03 ; nodeC.wirecolor = red

NormalizedVector = normalize(nodeB.pos - nodeA.pos)

NewVector = (NormalizedVector * magnatude) + nodeA.pos

nodeC.pos = NewVector



Cheers

Dan

[Bobo]

You misunderstood the Ray value. A RAY contains a start position AND DIRECTION. You cannot construct a ray from two positions - the second argument to the constructor is the direction vector.

If you have two positions, you don't even need a Ray to find the length along the direction they define.

If A is the starting point and B is the end point, then the vector defined by the two is
theVector = B-A

This vector will have a length equal to the distance between them and direction pointing from A to B.

So if you want to find a point at a given distance along the line connecting A to B, you just need a normalized vector (also called unit vector) which has the same direction and a length of 1.0.

theUnitVector = normalize theVector

You can multiply a vector by a scalar (integer or float value) to get a new vector with the desired length. Thus,

theNewVector = theUnitVector * 10

This is a vector that starts at 0,0,0 and has a length of 10 and is parallel to the direction defined by A->B. In order to find the position of 10 units along the line from A to B, just add theNewVector to the position A:

theNewPos = A + theNewVector

In short,

theNewPos = A + (normalize (B-A)) * 10

This is exactly what djlane wrote, but with some more theory to explain it.

If you want more, see my signature :)

[EricDLegare]

This is exactly what djlane wrote, but with some more theory to explain it.
Well thanks a lot :D

If you want more, see my signature :)
You can count on me for this :D Thanks again !

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