Forum

Welcome Guest 

Show/Hide Header

Welcome Guest, posting in this forum requires registration.





Pages: [1]
Author Topic: List of hotkeys?
TuneWithHa-
mmer
Newbie
Posts: 12
Permalink
Post List of hotkeys?
on: January 25, 2018, 21:57
Quote

I stumbled onto ctrl-i, which is very helpful.
Is there a list of hotkeys somewhere?

sandy
Administrator
Posts: 1317
Permalink
sandy
Post Re: List of hotkeys?
on: January 26, 2018, 00:05
Quote

I've just wrote up https://github.com/euphy/polargraph/wiki/Keyboard-shortcuts-in-the-Controller which has a couple extras. There's not many though, and some of them are weird!

TuneWithHa-
mmer
Newbie
Posts: 12
Permalink
Post Re: List of hotkeys?
on: January 26, 2018, 00:53
Quote

Thanks man!

Shorn
Beginner
Posts: 33
Permalink
Post Re: List of hotkeys?
on: February 21, 2018, 14:38
Quote

Sandy- how do I use this and by how I mean what is the scenario where I would want to play with this setting:

Geometry
< and >: increase and decrease the "maximum segment length" that controls how long vector art lines get chopped into. The default for this is 2 and the minimum is 1. This isn't something you can see a preview of.

The controller has an adjustable 'shortest vector'. I have played with the 'shortest vector' setting previously and could not quite get a visual sense of what it was doing despite understanding conceptually what it should be doing.

One seems to be a low-end filter and the other seems to break apart long vectors.

Are the vector lengths in mm or pixels?

-Shorn

Hardware:
*Running an Arduino Nano reflashed with an Uno bootloader
*Modified knockoff GRBL CNC shield with knockoff DRV8825 step drivers
*400mA -200 step motors set to 16x microstepping
*2mm belt with 36 tooth drive gears
*Machine set to 1500 Max speed and 5000 motor acceleration

Software:
*Stock Polargraph Controller to make command queues
*D2S version 2
*Send.py on remote Raspberry Pi

sandy
Administrator
Posts: 1317
Permalink
sandy
Post Re: List of hotkeys?
on: February 23, 2018, 19:39
Quote

I've refreshed my memory of this and can see why it's confusing, I think it's just wrong.

Shortest vector applies a _high_ pass filter to the vector art, so only lines that are longer than this value (measured in motor steps) are drawn. This was really designed to remove noise - small lines which are almost coincidental. If the short line is isolated on it's own, then it simply disappears. If the short line is in the middle of a long line, then it'll tend to get collapsed, and you'll end up with a long line left over.

The angles of the lines have no bearing on this filtering: only the length. It'd probably be a good idea to preview the effect, but right now you need to do a "draw vector" and see what gets built.

So that feature is related to cycle polygonizer and polygonizer length in practice. If you use polygonizer:1 with a short polygonizer length, then even your long straight lines get chopped up into short lines. Which makes them liable to be discarded by a low "shortest vector" setting. Can lead to some odd interactions.

The other setting is "max line segment length", there's no way to preview this except to draw it on paper, so I'll do an illustration.

Imagine you want to draw a horizontal line like this:

Image

The blue lines here are the grid of the natural axes of the Polargraph, so you can see the horizontal line is actually a kind of distorted diagonal as far as the machine is concerned. It can only really move a) directly along one of those blue lines (only one motor moving) or b) move two motors at once and move diagonally. Because of the odd nature of the coordinates system the diagonal still doesn't result in a straight line on the page, it's kind of hooked.

So to approximate a straight line on the page, the line is chopped up, and while each smaller line is a bit hooked, over all the line looks straight.

Max segment length controls the length of the segments. A long setting might chop this horizontal line into only six segments, and look like this which has significant and noticeable deviations from the intended path:

Image

while a short setting will mean the deviations are tiny, and possibly unnoticeable, once you take the natural hysteresis of the pen tip into account:

Image

Smaller setting are slower and noisier. You might use larger settings if you were drawing something very large that wasn't going to be looked at up close - or it was just an effect you likes. If you have noisy random looking images anyway, you might not notice it. On the other hand, there's a good chance that you already have lots of small lines on that, so they wouldn't tend to get chopped up anyway. If the straight line is smaller than your max segment length, then there's no chopping.

Hope that makes sense!

Sandy Noble

Shorn
Beginner
Posts: 33
Permalink
Post Re: List of hotkeys?
on: March 5, 2018, 17:24
Quote

Yeah, I think it all makes sense. Thanks for taking the time. I will probably setup a test image and do a batch drawings with it adjusting only those two parameters one at a time. Side by side comparisons helps me out a lot. If there is anything interesting or helpful I will post the results back.

-Shorn

Hardware:
*Running an Arduino Nano reflashed with an Uno bootloader
*Modified knockoff GRBL CNC shield with knockoff DRV8825 step drivers
*400mA -200 step motors set to 16x microstepping
*2mm belt with 36 tooth drive gears
*Machine set to 1500 Max speed and 5000 motor acceleration

Software:
*Stock Polargraph Controller to make command queues
*D2S version 2
*Send.py on remote Raspberry Pi

Pages: [1]
Mingle Forum by cartpauj
Version: 1.0.34 ; Page loaded in: 0.021 seconds.