How to interpret the transformations in the JSON output?

[PaulDL-RS]

Hello,

With the following solution,

final_translation_issue.json

I have a hard time rebuilding the nesting.

In particular, the Y-axis translation range from around -150 to +280 which doesn't fit inside a 130 height strip.
I assume the issue is with the point used as center for the rotation of the item in the first place.
Is it the centroid of the item ?

The rotation is clearly in radians, wich is also a bit of a coherence issue with the fact that input was in degrees (°).

Can you explain more how to handle the JSON output ?

Thank you,

Paul Durand-Lupinski

[JeroenGar]

Transformations are defined as a rotation (around the origin) followed by a translation.
This is why you can see y-translations range from [-150,280] with a strip height of 130.

You can play with the SVG source to get a visual understanding of how it works.
The JSON output matches the source code of the SVG:

<use transform="translate(420.0802 279.984), rotate(-180)" xlink:href="#item_0">
<title>item, id: 0, transf: [r: -180.000°, t: (420.080, 279.984)]</title>
</use>

{
  "item_id": 0,
  "transformation": {
    "rotation": -3.1415925,
    "translation": [
      420.0802,
      279.984
    ]
  }
}

The README should explain how it works, but maybe not clearly enough.
Let me know if you have any suggestions in clarifying the README