finding point on the vector

Unity Engine
1

i have two vectors that i use to render line. i am trying to get two points on the line that is 10% of the length distant from the end and beginning so actually i would render two lines that are part of the big line, check out the attachment

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any help appreciated!

2

Early morning maths…

  1. Get the length of the line
  2. Get percentage of that length i.e. ( length / 100 ) * x
  3. Get the directional vector of the line, times by step 2 result
  4. P1 plus step 3 result

Im sure theres a quicker way of doing this but its 9am.

3

Something like this I guess:

function SplitLine(p1 : Vector3, p2: Vector3, startDistance : float, endDistance : float) : Vector3[]
{
	var directionUnitVector : Vector3 = (p2 - p1).normalized;
	
	var p1EndPoint : Vector3 = p1 + (directionUnitVector * startDistance);
	var p2EndPoint : Vector3 = p2 + (-directionUnitVector * endDistance);
	
	return [p1EndPoint, p2EndPoint];
}
4

Lerp will come in handy here.

tenPercent = Vector3.Lerp(p1, p2, 0.10);
ninetyPercent = Vector3.Lerp(p1, p2, 0.90);

now you have your 4 points.

Lerp performs a linear interpolation between 2 values based on a percentage. (read up on the various permutations of Lerp/Slerp in the docs for specifics and differences of datatypes such as Lerp’ing a color variable)

5

I had a feeling there was something built-in that would do exactly this, thanks Mitch.

6

thank you all!