Computing Cosine Makes Geometry Vanish? 🎩

Grasshopper
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1

Hi,

In Rhino 8 (8.14.24345.15002, 2024-12-10) on macOS 14.7, computing the cosine in an Expression component in Grasshopper makes the geometry preview disappear from Rhino.

I’m not making this up, I swear.

Update:

It seems like all trigonometric functions and components are buggy and cause this issue.
It’s also not only the geometry preview that vanishes but baked geometries in Rhino as well.

Since the initial post I’ve rebooted the computer and relaunched Rhino a couple of times but the issue persists.

Thanks for taking a look.

2

That works just fine here in both the version you show and in latest internal 8.16 build.

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sin_cos_expression.gh (10.9 KB)

You’ll have to share a file that reproduces this issue for us to be able to investigate better.

3

Can I send you the file in private? It’s a hobby project, but I don’t want to share it publicly.
The bug rendered it unworkable, since the Rhino preview constantly disappears, when I want to do my math thing involving trigonometry.

4

In 8.15 (8.15.24352.13002, 2024-12-17), the problem persists, but when I open the file in the Release Candidate, I get the following weird error, which I didn’t get in the current Release.

Screenshot 2024-12-21 at 13.00.59
Screenshot 2024-12-21 at 13.00.59751×689 73.7 KB

The file still opens fine though.

5

This is most likely a division by zero problem.

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image2739×1525 313 KB

In my example, the box moves far away…

Zoom Extents adjusts the view like this:

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division_zero_null.gh (19.2 KB)

Replacing nulls helps.

1 Like
6

You misunderstood this, Martin. I’m not attempting to move the 3D geometry, but rather a point that is not visible in the video, I think. And all geometry vanishes from the Rhino viewport, not only what is moved.

7

Ok, but cos(pi/2) is 0…

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enable_this_and_everything_disappears.gh (18.5 KB)

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2 Likes
8

But you are moving geometry in your recordings. As @martinsiegrist points, dividing by 0 is a no-no.

2 Likes
9

You can do so using our upload tool. I prefilled my email address. Note though that I actually started holidays for two weeks, so if answering takes time you know why.

10

You’re right, guys! Thanks for being persistent with your ideas. This was totally an oversight on my part.
It’s indeed the division by zero that causes the issue, which deep down inside I know to be problematic for computers. :slight_smile:

Thanks.

1 Like