Polar pattern bug for angles < 360°

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mithrandil
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Joined: Tue Jun 20, 2017 8:56 am

Polar pattern bug for angles < 360°

Post by mithrandil »

That's not what one might expect from 180° polar pattern...

the slice is 360°/8 so 4 slices on 180° should be half a circle
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dbecad
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Re: Polar pattern bug for angles < 360°

Post by dbecad »

Mithrandil,
this is the classical poles & space problem, you only need 3 angles of 45 to pack the 4 slices in 180, so your angle should be 135degrees.
Cheers
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Jee-Bee
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Re: Polar pattern bug for angles < 360°

Post by Jee-Bee »

I ould like it that (even only a option to choose) i can set the spacing (in this case 45 degrees) and the number of instances.
Most of the time faster and more easy...
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DeepSOIC
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Re: Polar pattern bug for angles < 360°

Post by DeepSOIC »

Jee-Bee wrote: Tue Apr 17, 2018 7:01 pm I ould like it that (even only a option to choose) i can set the spacing (in this case 45 degrees) and the number of instances.
Most of the time faster and more easy...
In Lattice2 addon, it is possible. Use 'StepN' generator mode. But Lattice2 can't be used in PartDesign, yet. At least, directly... It may be possible via PD Boolean, I'm not sure.
mithrandil
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Re: Polar pattern bug for angles < 360°

Post by mithrandil »

dbecad wrote: Tue Apr 17, 2018 6:07 pm Mithrandil,
this is the classical poles & space problem, you only need 3 angles of 45 to pack the 4 slices in 180, so your angle should be 135degrees.
Cheers
Sure,
I found the same way of doing it,
but it seems kind of a workaround to me.

BTW you don't need 135°C to fit 4 slices of 45°, you need 135° to fit 3 more slices (so you should set the counter to +3...),

Otherwise you should also set 360°-45°=315° to fit the whole 8 slices circle, but what is set by default is 360°, not 315°...

Can you get my point?
dbecad
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Re: Polar pattern bug for angles < 360°

Post by dbecad »

You can also do it using a polar pattern angle formula like:
Sketch.Constraints.a * (PolarPattern.Occurrences - 1)
Where "a" is the slice angle name, then changing the number of occurrences does compute the right angle directly.
Cheers
mithrandil
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Re: Polar pattern bug for angles < 360°

Post by mithrandil »

Does this also make sense to you? (notice 1 ° of difference)

It totally doesn't!

Your solutions are workarounds, which are surely useful temporary solutions, but this is a bug which needs to be fixed.
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chrisb
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Re: Polar pattern bug for angles < 360°

Post by chrisb »

The 360° case is treated specially as a shortcut for "distribute the number of occurences over a whole circle".
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NormandC
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Re: Polar pattern bug for angles < 360°

Post by NormandC »

mithrandil wrote: Tue Apr 17, 2018 7:37 pm Can you get my point?
Your point is wrong.

In your first example, it is exactly what a 180-degree pattern should do. There is no bug there. It's not complicated: take your pie piece, and rotate it 180 degrees on the Z axis either using Part Placement or Draft Rotate. It will end up in the same exact position as the last occurrence in the polar pattern.

...And this is yet another topic that was wrongfully posted in the Part Design module development forum. Which description in the forum index indicates:
About the development of the Part Design module/workbench. PLEASE DO NOT POST HELP REQUESTS HERE!
Tell me, where exactly are we discussing development here?

You're wondering if it's a bug, OK; then please read the Bug submission guidelines topic:
2. If you are unsure, discuss the problem on the forum first. Open a new topic here on the forum, in the help section, and ask if what you found is a bug. Other users will surely be able to help you determining what you should do.
Moderators, part of your job is to move topics to the relevant forums when needed. When I was an admin, I was doing it all the time.
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