how can I check that one line is between two parallel lines or there is not?
I think you could stick to your original post here.
This is kinda a double post in my opinion.
this way might be a possibility
here is if you want to try ''Play" (M. Alien games are better)
15 Mai Forum anglais rep Line between.dyn (23.6 KB)
As long as the middle line falls within the extents of the two outside lines, then you can utilize the method that @christian.stan suggested. However, if you have a condition similar to below and you are considering this to be a true occurrence, then it gets a little more tricky.
with a projection in this case on the median line, But Mr. Jacob told me that this was resource-intensive
edit: by ordering the coordinates can be a track in this case
You can also create a loft surface with two lines and then check the intersection between the surface and the line.
I haven’t tested this, but it is worth a shot.
Build a vector from the start point of line one to a point on the line to test, and a point on line two to a point on the line to test. These are the test vectors.
Then build the control vector from line 1 to line two. This is the control vector.
If the angle between the control vector and the test vector is less than 90 degrees (meaning everything was moving from the first line towards the second) then the first point is between the two end points.
Next do the same for the end points of each line. If both tests are true, I think that proves the line to test is contained.
This should work for test lines ‘between the ends’ of the control lines, or further out in space.