Sweep2 doesn't give G2

unhandled

#1

Hello, why when using Sweep2 not G2 turns out (but setup is present)?
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Untitled.3dm (108.8 KB)


(Pascal Golay) #2

Hello - Please keep in mind that there is a tolerance in the match, and that the false color display always comes from a mesh, so there is some approximation happening there as well . In any case, here I do not see even that ‘line’ in the display.

-Pascal


#3

You can apply a screen of this place (CurvatureAnalysis, Gaussian):
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#4

Unless it only false display?
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#5

If to apply MatchSrf to the existing surfaces, then the situation only worsens:
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At BlendSrf it turns out more smooth:
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#6

Why CurvatureAnalysis gives the wrong data? @TomTom, @Lagom, @davidcockey, @Micha


(David Cockey) #7

Why do you believe curvature analysis gives wrong data?

Which curvature analysis? Guassian, Mean, Min radius, Max radius?

How are you setting the range?


#8

What is “wrong” in your specific case? What do you expect to see and why?


#9

Other analyses show good result. I use Guassian and Mean. I use the Auto Range button.


#10

The analysis of Zebra - everything is excellent! And at CurvatureAnalysis everything is bad.


(David Cockey) #11

Why do you say it is “bad”? What are you using Rhino for?


#12

In my case smooth surface. And I think curvature shouldn’t break so… MatchSrf causes big breaks, it is normal?


#13

With MatchSrf, you can obtain G0, G1 or G2 continuity. If your surfaces have a good CP structure, you will succeed. Sometimes, a little bit of CP moving is necessary afterwards.


#14

At me with points everything is good, but MatchSrf yields bad result - you watch the top posts.


#15

Looks ok to me with Sweep2 and Curvature.


#16

At me on rails such defect turns out:
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I apply MatchSrf and the defect vanishes:
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But earlier something turned out like it:


Why? Very strange…


(David Cockey) #17

MatchSrf and BlendSrf work differently.

BlendSrf creates a new surface. The new surface has enough control points in the direction between the adjacent surfaces to satisfy the match conditions. The degree of the new surface in that direction will be number of control points minus 1 so that it is single span.

MatchSrf uses the existing surfaces. It maintains the existing degrees and number of control points of the surfaces if sufficient to satisfy the match conditions. If needed it adds control points and increases the degree of the surface(s). The shape after MatchSrf depends on the initial control point arrangement.


(David Cockey) #18

The differences you are seeing are the result of how the different algorithms work. What you perceive as “bad” is probably limitations in the calculation and display of surface curvature.

Have you tried changing the mesh settings in CurvatureAnalysis? If so does that change what you perceive as problems?

Will you surfaces be used for anything?


#19

Settings of a grid don’t influence breaks, and the surface will be only an object.


(David Cockey) #20

Have you confirmed that the mesh settings do not affect what you see as problems?

How accurately will the physical objects be made?