Scaling problems

So, I’m trying to use my iPad and the Glowforge ios app. The flow seems to work just fine, except when I copy from Vectornator to the Glowforge app, the image is scaled differently. What was 7.5 inches in Vectornator is now 5.5 inches in the Glowforge app.

Anyone experience this and know a solution?

Likely a DPI issue. Do you have the ability to set a canvas of artboard size in that program?

By setting a 12x20” artboard, the Glowforge app will know exactly how to scale objects that are defined in pixels.

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It’s got to be something like that. I created a 12x20 canvas, created a 10x10 square and exported to Glowforge. It showed up as 7.5x7.5.

Looking at the canvas though, I think it’s 72 dpi. I can switch from inches to points or pixels and it shows 1440 x 864.

So, 25% reduction means dpi is low in Vectornator with respect to the Glowforge app perhaps? So gf expects 90 dpi? Or is it too late and the brain isn’t working? (Even odds in my mind).

Anyone know for sure what gf expects?

Quick search says gfui expects 96 dpi…

Which, there you go.

Well, edit, I read it wrong.

72/96 = 5.6/7.5

Mystery sort of solved.

Was your 5.5 an estimate? 5.6 is pretty close.
Edit edit, no, I read it correctly, you tested a 10" later. 7.5/10 is the same as 72/96, so it seems your dpi is incorrect in your editor.

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So it’s not so much what the app is doing - it’s a result of things being browser-based. Don’t quote me, but, without any different scaling set up in the OS, it should be 96 PPI.

The app you’re using might be specifying things in inches, but it really comes down to how it’s exporting out the SVG; if it’s specifying things in pixels (or not specifying any units, just numbers, which are interpreted as pixels), that’s where you’re going to run into trouble.

Long ago, GF created the 12x20 hack (it will actually work with any dimension as long as the aspect ratio is correct), and it should pin the work to the top left of the work area.

This is an awesome trick for having things show up exactly where you want them to.

The GF UI is accurate to fractions of a mm with a correctly formatted file.

Note that plain SVG files from applications like Inkscape don’t even specify DPI. They only have absolute units (I work in mm) and they are defined with 0.00001mm precision, for example.

The issue is with your file. Never heard of Vectornator I’m afraid. Inkscape is free and quite popular.

Please see this posting for a workaround:

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