Trim Bug in WIP

Serengeti (Rhino WIP)
1

In Rhino 6 WIP I’ve noticed a weird issue when using the Trim command on multiple intersecting curves. To illustrate I made this quick example using the “Circle tangent to 3 curves” command:

Top_01
Top_011333×750 95.4 KB

Trim functions perfectly while in the Top View:

Top_02-Trim
Top_02-Trim1333×750 79.8 KB

However the problem arises when using Trim in the Perspective view:

Perspective_01
Perspective_011333×750 437 KB

Perspective_02-Trim
Perspective_02-Trim1333×750 404 KB

The curves do not split at the correct locations and clicking on those protruding tails just makes them split apart further into smaller segments.

2

That works fine here so there is something more file- or system-specific going on. Would you mind sharing a 3dm file?

3

Here’s my 3dm.Trim_Bug_01.3dm (53.2 KB)

4

I can reproduce this when I turn ApparentIntersections on.
I always keep mine at No, so this doesn’t bother me… :innocent:

5

This still happens to me even when turning off ApparentIntersections, which I’m glad to learn can be turned off by the way. :slight_smile:

6

Hi Derek, Wim - thanks for the report.
https://mcneel.myjetbrains.com/youtrack/issue/RH-43352

-Pascal

7

Hi Pascal,
I’m not sure if that means that you got it reproduced that it also does that with apparents turned OFF…
-w

8

Hi Wim - here it is as you-all described - with ApparentIntersections=Yes the trimming is weird, with No, it’s OK.

-Pascal

9

Am I reading this wrong? :hear_no_evil:

10

ork. I see - well, here, with Apparent=No, the trims work as expected…

@Derek_Heming - can you verify that it does not work right for you is ApparentIntersections=No ?

-Pascal

11

Same here…

12

Sorry, I should have worded that more clearly. Yes this trim bug still happens for me in perspective whether ApparentIntersections=No or ApparentIntersections=Yes.

13

Hi Doug - ok, thanks, I’ve added a note to the YT item.

-Pascal

14

I looked at this bug and the problem I found required 3 things to make it happen

  1. The object picked to be trimmed was also chosen as a cutter.
  2. Apperent intersections set to true. In this case the the cutters are transformed to screen coordinates.
    without this option I believe the test that the cutter and the to_be_trimmed are the same object would make it so step 3 would not be used.
  3. The intersection of the 2d screen coordinate cutter and 2d to_be_trimmed curves was not a total overlap( i.e. from end to end) as it should have been.
15

RH-43352 is fixed in the latest WIP

16

Excellent news, thank you.