# Tag Info

6

Ok, Xenapior and Reynolds together have the right idea. But the explanation is a bit lacking so here is a image to explain it all and some further musings. First let us start by drawing an image (yes i know that is what they say in school for you to do but nobody does it). From the image we can see that there are 2 equal right triangles $V_2, A, C$ and \$...

6

An alternative way to formulate the problem is to define a function that gives the distance between points on the two curves, as a function of the curves' parameters. Then attempt to find the global minimum of this function. If the curves intersect, the minimum will be zero; otherwise the minimum will be some positive distance. To be explicit, given a pair ...

5

[Disclaimer: I think the following should work but have not actually coded it myself] I couldn't think of a "trivial" method of producing a yes/no answer but the following would be a reasonable approach to a practical solution to the question. Let's assume our curves are A(s) and B(t) with control points {A0, A1..An} and {B0,..Bm} respectively. It seems ...

4

Depends on the CAD program. But yes basically they do just what you describe they triangulate the model into a mesh/lines on demand and then display that. How they chose to do this depends on the CAD, most modernized codebases probably use buffers. But older cads may in fact use the old immediate mode draw calls. This said it is possible that the ...

3

Its called a geometric constraints solver (a good primer on subject). You can find a open source solver as part of Open Cascade but its a bit convoluted to get going. A simpler solution for just solving, but also 3D solver capable, is geosolver. Making your own (algebraic solution being easiest to write) is also not that hard, just a bit of work to make it ...

2

The cut length from the vertex is x*ctan(t/2), where t is the angle at this vertex.

2

I suppose you want an arc of C0 and C1 continuity between the line and an arc. As illustrated above, you already have a vertex A which is the intersection of an edge and an arc of which the center positioned at O and radius equal to R. The question is thus pure mathematical: given A,O,R, edge direction BA, and a corner radius r, find C,B, and T. For ...

2

Since you have a limited set of tools you are not actually doing a classical fitting. What you have is a discrete problem. And since you are looking for a somewhat easily drawn fit, no more than twice segmented for example. One way to approach this is to find all the points that match your curvature requirements. Then find the point x units away from point ...

1

The relative size of the spacing of knots is irrelevant for the NURBS curve. The only thing that matters is that they keep the relation. Note this may not be wise as parametrization may have other uses behind the scenes. Image 1: 3 differently parametrized knots result in same curve if knot values are relatively the same. So you can scale and offset knot ...

1

Since you're working on CAD software, you probably want some precise results. Here an algorithm that could work: For each side: Compute the segment's equation. Compute each round corner's circle equation. Compute the intersections between the segment and each circle. The 2 intersection points are the new endpoints for the line segment. This doesn't handle ...

1

There is no general algorithm for packing problems. Only some of the special cases have known, and optimal, solutions. If you are packing one shape then finding a reasonable solution is possible. Like the known cases of hexagonal packing etc. However, if you have multiple diffenently sized objects then easy just flew out of the door. Some heurestics have ...

Only top voted, non community-wiki answers of a minimum length are eligible