[Grida Canvas] Rotation handle origin sensitive rotation gesture

[softmarshmallow]

Summary

The rotation handle works, but its behaviour is somewhat unexpected, resulting poor control & ux.

The current rotation gesture does not care about its rotation handle origin, simply takes the mouse movement as a angle,
Which instead, it should calculate the rotation based on the handle origin.

Details & Examples

We have 4 rotation control points per each node overlay.

• nw (top left)
• ne (top right)
• se (bottom right)
• sw (bottom left)

Let's say we have a 0, 0, 100, 100 rectangle, (100x100 rectangle at 0,0)
The each control points would be placed at

• nw 0, 0
• ne 100, 0
• se 100, 100
• sw 0, 100

The rotation will apply based on the center point, (50, 50) and the amount of new angle to be applied shall be calculated based on the mouse movement and the rotation handle origin.

Current behaviour

Screen.Recording.2025-01-07.at.3.50.09.AM.mov

Expected

Screen.Recording.2025-01-07.at.3.51.51.AM.mov

Bonus

While we do this, we also need to adjust the svg cursor rotation, to make the rotation handle cursor rotate as well as we rotate.

[ramu-narasinga]

Can I work on this please? Thanks.

[softmarshmallow]

@ramu-narasinga Assigned! Go shoot