Select edge for rotation

LightBurn Software Questions Tips and Tricks
1

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I need to rotate this object back to the “circled” line being vertical. Is there any way to:

  • find out the angle it is at so that I can enter the necessary angle into the rotation field. I tried drawing a line along it and then looking for it’s angle, but couldn’t find it.
  • selecting a line/segment in a drawing and getting it’s angle from vert/horiz to do the rotation.
    I just eyeballed his one this time, but wondered if there was a better way.
2

There isn’t a way to do this in LightBurn at the moment, but it happens to be on my own personal wish list. We’ll need a bit of infrastructure to do it (need to be able to select two points, then choose “un-rotate” or something like that).

3

G’day Oz
I’ve just been experimenting with drawing 2 lines (that snap feature makes the first line easy), but it’s getting the second line perfect that’s the trick. It will be a nice feature if it can be incorporated, but for now this is quite close!

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4

I use a temporary box as my guide edge and rotate to align:

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5

Should have mentioned that the little circled -0.33 is the dy value, and that was as close as I could get it to 0.0. I think if I go for a really long line I should be able to get closer - radial movement and all that. The box method I will try too!

1 Like
6

There is always math by way of leveraging the box:

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https://www.mathsisfun.com/algebra/trig-finding-angle-right-triangle.html

7

Here is my proof:

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8

OMG, @PCO you just showed me something I never paid any attention to. Forget the math example! Wouldn’t you know the computer (LightBurn) already does it. You were just measuring the wrong side of the angle.

Solution =

Draw box snapped on upper and lower segments then use those nodes to find angle! WOW. It was right down there this whole time.

Look at the bottom of the screen when I draw the two line segments, you will find the same 11 degree angle:

9

I just tried that - absolute ripper - it works and is so much easier than the maths or the buggerising around that I was doing. As a maths teacher I’d also rather not do maths when I’m supposed to be having fun :wink:

10

I like hiding things in plain sight, where no one will ever find them, remember?

The documentation for the line tool:

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11

G’day Oz
This was where I got my idea from, I did the unthinkable and started reading the documentation and blog… extreme, right?! I like to live dangerously!
As is often the case, once we all have a look at the problem solutions start coming out of the woodwork. It is testament to the plethora of features in this fantastic package!
Money well spent. Thank you!
Cheers
Pete

1 Like
12

There’s always one. :slight_smile:

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