Take into account of parent transforms

[Happypig375]

No description provided.

[Happypig375]

@mrbean-bremen Re-run?

[H1Gdev]

What kind of SVG will this PR improve ?

[Happypig375]

@H1Gdev

<svg viewBox="0 0 100 100">
  <text transform="translate(10 30)">
    <tspan id="target">ABC</tspan>
  </text>
</svg>

Bounds of tspan from view box should match text

[H1Gdev]

Thanks.

What happens with this SVG ?

<svg xmlns="http://www.w3.org/2000/svg" version="1.1" width="100" height="100">
  <text>
    <tspan transform="translate(10 30)">ABC</tspan>
  </text>
</svg>

Many major browsers don't show anything for this SVG. (transform in <tspan> seems to be ignored.)

[Happypig375]

<tspan> doesn't support transforms by itself, correct. But its bounds should use its parent transforms to result in the same bounds for the <text> and <tspan> elements since they do represent the same text at the same location.

[H1Gdev]

It doesn't seem to work properly with latest master, can it be fixed by merging this PR ?

[Happypig375]

Yes, this is what I aim to fix.

[H1Gdev]

It doesn't seem to be fixed...
This SVG should not show anything because <tspan> transform is invalid.

[Happypig375]

In this case, it's the problem of the parser, and Bounds just takes information from the object tree. Out of scope.

[Happypig375]

<svg viewBox="0 0 100 100">
  <text transform="translate(10 30)">
    <tspan id="target">ABC</tspan>
  </text>
</svg>

This PR fixes this, and this only.

[Happypig375]

Hmm, actually this issue may exist across different element types, not just <tspan>.

[Happypig375]

Superceded by #945