Add "new viewport port" support [ fix for issue #1137 ]

[kabab]

No description provided.

[asturur]

how does this lofic behaves with viewboxes that have a scaling factor?

[kabab]

Will it s not about the viewBox attribute, you can check issue#1137 to understand the problem.

[asturur]

i understand the problem of the x and y attribute of the inner svg tag.
i`m asking if you checked this logic in combination with viewboxes attribute that have a scaling factor.

Does it stack correctly?

example:

<svg xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" xml:space="preserve" width="1000" height="1000" viewBox="-10 -50 100 950" preserveAspectRatio="none">

<svg preserveAspectRatio="none" x="12" y="12" width="300" height="400" style="fill: none;" viewBox="0 0 300 400">
    <rect x="2" y="2" width="100" height="80" fill="blue"/>
</svg>
<svg preserveAspectRatio="none" x="12" y="12" width="300" height="300" style="fill: none;" viewBox="0 0 250 300">
    <rect x="2" y="2" width="100" height="80" fill="red" opacity="0.5" />
</svg>
<svg preserveAspectRatio="none" x="-12" y="-12" width="300" height="300" style="fill: none;" viewBox="0 0 150 300">
    <rect x="2" y="2" width="100" height="80" fill="orange"/>
    <svg preserveAspectRatio="none" x="10" y="10" width="300" height="150" style="fill: none;" viewBox="0 0 200 300">
        <rect x="10" y="10" width="100" height="60" fill="red"/>
    </svg>
</svg>
<svg preserveAspectRatio="none" x="0" y="0" width="300" height="300" style="fill: none;" viewBox="0 0 250 250">
    <svg preserveAspectRatio="none" x="12" y="12" width="300" height="300" style="fill: none;" viewBox="0 0 300 300">
        <rect x="2" y="2" width="100" height="80" fill="green" opacity="0.1" />
    </svg>
</svg>
<svg preserveAspectRatio="none" x="0" y="100" width="3000" height="1500" style="fill: none;" viewBox="0 0 160 180">
    <rect x="10" y="10" width="10" height="60" fill="green"/>
</svg>
</svg>

is this svg rendering good?

[kabab]

@asturur for the time being this pull request solve just (x, y) attribute problem.

[asturur]

please check #2399 for a more complete solution.

[asturur]

merged 2399.
thanks for giving input.