Hi all,

i have these series of curves and i want to create a vectors along these curves in order to be able to create a circle based on that vector which will be a normal vector for circles

Thanks

Hi all,

i have these series of curves and i want to create a vectors along these curves in order to be able to create a circle based on that vector which will be a normal vector for circles

Thanks

Whatâs wrong with what you are showing right now? I donât see any errors. Please be clear about what exactly you need. If necessary provide a diagramâŚ

is there a node can give the normal vector along a specific line?

Normal is a vector that is perpendicular to a surface. There is no such thing as line normal. https://en.wikipedia.org/wiki/Normal_(geometry)

I think you may be looking for Curve.TangentAtParameter âŚ

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If I understood you correctly, if you get the CoordinateSystem of the curve with the node âCurve.CoordinateSystemAtParameterâ and then get itâs axis youâll have it for each point at the parameter youâve set (0âŚ1). I am just not sure which axis you should get, but I guess it is XAxis. For this youâll need to use the node âCoordinateSystem.XAxisâ (or YAxis/ZAxis)

@Andreas_Dieckmann I might be wrong but there is no tangent to a line. OP has a polyline in that image. Any tangent line will return a line that is equal to the input lineâŚwhich is actually technically wrong since tangent should touch the curve at one point onlyâŚjust saying.

@ricardoperucci yeah, I think you are right. I have no clue what the OP wants, but I can guess that he wants a perpendicular plane or a Coordinate System at line, and then extracting X axis from it, which would be a line perpendicular to an input line. There is no guarantee as to direction of such line which would be dependant on input line direction itself.

Haha @Konrad_K_Sobon, should have worn my glasses

All lines (curves for generalisation) have tangents and normals. Even straight lines have tangents; youâre right that the vector is the line itself (colinear), however tangents are defined from a parameter on the curve and an algebraic expression, not by what they âtouchâ.

Ps: That wiki link states:

For example, in the two-dimensional case, the normal line to a curve at a given point is the line perpendicular to the tangent line to the curve at the point.