Bug in text width computation

[Shap]

Scenario: a text item with text-anchor:middle contains
two tspans. The first tspan has no style attributes.
The second has a font size change. The text item as a
whole renders with a correctly computed middle anchor
point.

Now add a y parameter to the second tspan. The second
tspan now renders at the correct y position, but the
width computation on the containing tspan is now
computed incorrectly, with the effect that the
text-anchor center computation fails to consider this
tspan element.

The attached file renders correctly in Adobe's SVG
plugin, but incorrectly in inkscape. Removing the Y
parameter from any of the tspans to see how the text
anchor computation changes. It is most obvious in the
PX box at the upper right.

[Shap (shap)]

Sorry. I should have mentioned that this was happening in
Inkscape 0.43 on Linux, but I suspect it's a generic bug.

[Shap (shap)]

Hmm. Text handling is worse than I thought. The file icw.svg
renders to postscript with correct text widths if asked to
render a monospace font. Now change all appearances of
'monospace' to 'sans-serif'. Text width computations are now
badly off.

So I think we need to generalize this bug to state that text
width computations are not being performed properly.

[Rwst (rwst)]

I confirm that the file testme.svg renders different in
Batik vs. inkscape

[Mercury (mercury13)]

Cannot test, but sometimes Inkscape writes text size as "100", sometimes as "100px".

[jazzynico (jazzynico)]

Reproduced on Windows XP, Inkscape 0.48.2 and revision 10923.

Related Bug #168023 "text-anchor incorrectly inherited in tspan".

[Beluga (buovjaga)]

What I see in Inkscape vs. Firefox or LibreOffice is that there is a (1) on the right side of PX, outside of the box.

Win 7 64-bit
Inkscape 0.92pre1_64bit r15016

[Jonathan Hofinger (jhofinger)]

In 0.92.4 and 1.1-dev (6b4d57f, 2020-04-01), Windows 10:

testme.svg:
- The (1) is outside of the box. Inkscape renders it as such, Firefox and Chrome don't. That's expected and not a bug.
- Apart from that, I can't spot any differences.

icw.svg:
- The baseline-shift attribute is ignored by Firefox and accepted by Chrome and Inkscape.
- Apart from that, they render the file identically.

Closing as not reproducible in recent versions.

Please reopen on http://inkscape.org/report if the problem occurs again.

Closed by: https://gitlab.com/jhofinger