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[Xypron <653315@xxxxxxxxxxxxxxxxxx>]

Hello Alvin,

the SVG file in question was create manually. It is rendered correctly 
in Firefox and other browsers because it is SVG compliant.

Obviously Inkscape implements only part of the SVG specification. It 
should be changed to support elliptic arcs without approximation.

Best regards

Xypron

Alvin Penner wrote:
>      sorry, I misspoke myself. The situation is more complicated than I thought. It is true that the original file contains only true arc elements, no Bezier curves. But when you edit it, you see the handles typical of Bezier curves, you do not see the handles typical of an arc. (using the Node tool to draw this distinction) The reason apparently is that the object has no sodipodi attributes, which suggests that perhaps it was not created by Inkscape. In the absence of sodipodi attributes, the editing and probably also the rendering will be done using Bezier curves.
>      So the question is, why is the Bezier approximation so poor. The reason is that the arc angle is too high. In the curved portion of the 'p', the outer curve section is represented by only 2 Bezier curves and they both have an arc angle greater than 90 degrees. The Bezier approximation to an arc very rapidly becomes very poor if the arc angle is allowed to be higher than 90 degrees.
>      So the next question is, why is file p_new.svg better, after manually expanding the image? Because this file contains 8 Bezier curves, not 2, in the same curved portion of the 'p' character.
>      I suspect, but obviously cannot prove, that the approximation procedure that converts from arc to Bezier probably has some numerical cutoff that determines how many segments to use and that this cutoff value is in absolute units not scaled units, so that when you convert a tiny image (200 times smaller than normal) you get fewer Bezier segments than when you convert a normal size image, leading to a situation where a very tiny image is not as well-formed as a normal size image.
>
>

-- 
Bezier curves drawn, where svg file requires circular arcs
https://bugs.launchpad.net/bugs/653315
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