Pencil & Caligraphy: Interpolation tolerance in final path

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avazquezr
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Pencil & Caligraphy: Interpolation tolerance in final path

Postby avazquezr » Mon Oct 27, 2008 4:37 am

Hi all,

I'd like to choose the degree with which Inkscape interpolates my mouse input when drawing with :tool_pencil: or with :tool_calligraphic:

It seems that Development team has been working on improving the curve fitting on both tools
https://bugs.launchpad.net/inkscape/+bug/188849

Is there any way to control how sensitive the final path is to the movement of my mouse? Something like the path's "CurveFit" (in px, mm, etc.) attribute in Adobe Photoshop.

Thank you,

AvazquezR

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prkos
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Re: Pencil & Caligraphy: Interpolation tolerance in final path

Postby prkos » Mon Oct 27, 2008 5:26 am

I tried that feature (from the bug) when it was implemented and it works great, you can see the shape change after you release the mouse.

It doesn't seem to be there on the version I currently use, I guess it's because it needs to be adjusted as noted in the bug report.

Until then use the Simplify option, and in the development builds use Smoothing option that simplifies automatically.
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avazquezr
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Re: Pencil & Caligraphy: Interpolation tolerance in final path

Postby avazquezr » Mon Oct 27, 2008 5:44 am

Thank you prkos,

I would actually like the :tool_calligraphic: and :tool_pencil: tools to not do any interpolation at all (or very little at least). A simpler solution could be giving the user the possibility to enable or disable interpolation (e.g. Inkscape would generate a new node for each pixel the mouse traces).

I'm interested in controlling the interpolation tolerance because I do a lot of handwriting on Inkscape with a Wacom tablet. The interpolation in Inkscape tends to oversimplify my handwriting to the point that it makes some words or letters illegible.

Disabling the interpolation would make :tool_calligraphic: and :tool_pencil: tools behave like a free-hand tool in a classic bitmap editor (such as Pain.NET). Adjusting the interpolation would be like setting the CurveFit attribute to 1px or 0px in Adobe Photoshop.

PS: Is there anyway to access any of these (possible hidden) parameters via scripting in Python?

Best,

Amelio

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prkos
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Re: Pencil & Caligraphy: Interpolation tolerance in final path

Postby prkos » Mon Oct 27, 2008 7:36 am

I think you better send this to the Inkscape dev mailing list ;) I think mouse sensitivity to movement is very technical question.

I get a lot of nodes (like 1 node per pixel you mentioned) if I draw slowly with the Pencil.

Have you tried Mass option of the Calligraphy tool? I find 0.1 (10 in dev build) works nice for a mouse, maybe tablet needs it different.
just hand over the chocolate and nobody gets hurt

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very comprehensive Inkscape guide
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microUgly
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Re: Pencil & Caligraphy: Interpolation tolerance in final path

Postby microUgly » Mon Oct 27, 2008 11:51 am

prkos wrote:I get a lot of nodes (like 1 node per pixel you mentioned) if I draw slowly with the Pencil.

I've found that drawing as slow as possible results in segment lengths 15px long.

Although, I'm pretty sure the same version of Inkscape on my other PC produces much shorter segments--I've noted to myself before how easily I draw smooth paths on one PC and not the other. I questioned if it had something to do with processing power.

avazquezr
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Re: Pencil & Caligraphy: Interpolation tolerance in final path

Postby avazquezr » Tue Oct 28, 2008 12:52 am

Thank you. I get better results with :tool_calligraphic: than with :tool_pencil: It seems that the interpolation scheme they use is different. This is more noticeable when drawing small objects, as when handwriting at 14-point size &100% zoom with a wacom tablet.

The mass attribute in :tool_calligraphic: affects the smoothness of the final path. This attribute somehow filters the mouse input, so it does have an effect on the interpolation (it does something similar as the CurveFit attribute in PhotoShop)

I'll check with the dev team for the interpolation tolerance issues with the :tool_pencil:

Thanks!

Best,

AVazquezR

avazquezr
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Re: Pencil & Caligraphy: Interpolation tolerance in final path

Postby avazquezr » Tue Oct 28, 2008 1:36 am

I just found out that the Dev team is working on it! :)
https://bugs.launchpad.net/inkscape/+bug/188381

See an example here: http://img206.imageshack.us/img206/106/tolerancecp9.png

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prkos
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Re: Pencil & Caligraphy: Interpolation tolerance in final path

Postby prkos » Tue Oct 28, 2008 8:51 am

avazquezr wrote:I just found out that the Dev team is working on it! :)
https://bugs.launchpad.net/inkscape/+bug/188381

See an example here: http://img206.imageshack.us/img206/106/tolerancecp9.png

I that might be the Smoothing operation I mentioned above.
just hand over the chocolate and nobody gets hurt

Inkscape Manual on Floss
Inkscape FAQ
very comprehensive Inkscape guide
Inkscape 0.48 Illustrator's Cookbook - 109 recipes to learn and explore Inkscape - with SVG examples to download


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