Export of straight segments to PDF triggers pixel fitting

[TylerDurden]

Related to Question: https://answers.launchpad.net/inkscape/+question/663792

Automatic or manually converted text-to-path saved as PDF frequently has thicker/thinner vertical lines on san-serif characters like lowercase "l". Horizontal lines may also be affected. This is very common and pronounced on small text.

It appears the export (save copy as) to PDF involves some pixel fitting, as the level of zoom on the resulting pdf changes the width of these lines.

This can be mitigated to a great degree by converting straight segments to curve, without distorting the shale of the lines. Export (save copy as) to PDF shows little variation in thickness at arbitrary zoom levels.

Considering the beneficial result of the conversion of straight segments to curves, it might be possible to include that operation in the PDF export dialog when the radio-button for "Convert texts to paths" is selected.

Examples attached.

TD

[Patrick Storz (ede123)]

Are you sure that what you're seeing is not simply some hinting functionality applied by your PDF viewer? From what I can tell the geometric shapes are identical, so any difference in appearance is a characteristic of the renderer.

A good renderer probably tries to draw straight lines in a way so they coincide with physical pixels which explains why the behavior you're seeing becomes more pronounced at small zoom levels.

That being said I can see how forcing the renderer to disable this feature might be desirable in some cases if the path represents text - then again I don't see why I should not simply embed fonts into the PDF if text rendering is important to me.
Telling Inkscape to create paths instead of creating proper text but at the same time telling it to try to optimize those paths to ensure that they render more as if they were proper text is kind of working in opposite directions.

[Patrick Storz (ede123)]

P.S. The example images in the question seem to suggest something else is going wrong there, as the geometric shape seems to change significantly (text becomes a lot larger in the second screen-shot).

So unless Adobe Reader does something super-smart here I'm having a hard time to attributing this to the same effect...

[linuxjh (linuxjh)]

Hi Eduard,

We use the "text to path" option and want the PDF exported

1) to be "copy protected" (no selection and copy) and
2) can be switched to Outline view in Adobe Illustrator

I open the PDF file in illustrator. It shows the overlap too.

https://raw.githubusercontent.com/linuxjh/repo/master/misc/pdf-text-to-paths-illustrator-outline.png

Thanks