Point Intersecion Error


#1

I have a curve that I have divided into XYZ points and then extracted one of these points. This point I have then replugged into another point directly to check it intersects the curve which comes back saying true. However when I use the values for this point and insert them into a point manually it says it doesn’t intersect the curve. They are the same point so why?

Point IntersectionDYN


#2

Likely, this is a double or rounding error, please file this a Github issue, Dynamo is hiding the trailing digits but these numbers are actually doubles, and so it seems you are not able to enter the full components of the point.

Dynamo displays 7.818 to you, but the real number may be 7.818656353759xxxx etc.

a workaround would be to project that point to the curve, then check if the distance between the projected point and the original point is very small…


#3

Hello Mark Thorley,

You can control number of digits to be displayed using menu option Setting>NumberFormat, but there you can set up to 4 digits.

But as Michael Kirschner said, it is a tolerance issue and that is the reason you are not getting correct result.

I will log a improvement issue for tracking this internally.

Thanks,

Ritesh

 


#4

I had a similar problem that I spoke with Zach about due to the tolerance issue and additional decimal places past the allowed 4. This is giving me a massive headache at the moment, as points I require to intersect say they don’t due to recurring decimal places and how the number is rounded, even though the points display at the same place.


#5

Hey Mark, the easiest solution I can think of now is to define a tolerance, and instead of using intersection, create a vector by the two points for instance, then grab the length of the vector and check if it’s under the tolerance or not.