How to produce better results in DXF exchange?

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Krischu
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Joined: Thu Jul 04, 2019 8:11 am

How to produce better results in DXF exchange?

Post by Krischu » Fri Jul 12, 2019 10:54 am

I found that Qcad sometimes changes coordinates or lengths slightly. E.g. when join a line with an arc endpoint, it happens, that when I later import the DXF to Blender, that there is a gap between the arc endpoint and the line (healing required). Also line lengths or angles begin to change during working (translating, mirroing, copying). Has a line been of length 7mm, then it becomes 6.996 mm suddenly.

Haven't yet found out under which circumstances this happens but it makes the DXF unsuitable for importing into Blender, or saying the least, difficult to handle.

I'm seeking for a way to improve the exchange between QCad and Blender. Possibly drop Qcad and use Blender instead? This couldn't be it :)

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Husky
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Re: How to produce better results in DXF exchange?

Post by Husky » Fri Jul 12, 2019 7:01 pm

Krischu wrote:
Fri Jul 12, 2019 10:54 am
I found that Qcad sometimes changes coordinates or lengths slightly.
Personal I have never experienced that!
Krischu wrote:
Fri Jul 12, 2019 10:54 am
E.g. when join a line with an arc endpoint, it happens, that when I later import the DXF to Blender, that there is a gap between the arc endpoint and the line (healing required).
That sounds to me to be the answer of you question. Blender's import function changes the dxf coordinates or lengths. Sounds to me it could be a scale / unit converting issue.
Krischu wrote:
Fri Jul 12, 2019 10:54 am
I'm seeking for a way to improve the exchange between QCad and Blender.
It looks like you already encircle the issue. Look on the Blender side for all import option.

We are happy to help you with QCAD but for Blender you have to do your own research or ask in the appropriate Blender forums. Good luck!
Work smart, not hard: QCad Pro

CVH
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Location: Belgium; Antwerp

Re: How to produce better results in DXF exchange?

Post by CVH » Tue Jul 30, 2019 4:22 pm

I've also came across slight difference I am pretty sure I did not drew that way.
Drawing in mm usually in the sub 10^-8 range.
But sometimes more pronounced too and very rarely up to several 10th's.
Nothing I could reproduce myself untill present.
I don't swap platforms.

CVH
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Location: Belgium; Antwerp

Re: How to produce better results in DXF exchange?

Post by CVH » Wed Aug 07, 2019 9:00 pm

Got it again.

Drew something snapped to grid, 80 wide and centered.
One side is at -40.000000 the other at 40.000000.
All fine, at least up to the 6 digits displayed.
Three days later, and a lot of editing on many but the layer in question.
I needed the references on that layer again.
Referencing did not exactly as expected and then it struck me.

Now it seems to sit at -40.000037 and 39.999964 and it is a farction larger then 80.

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