Transformation/centre changes

[Cloud7050]

Current behaviour:

• Scale moves about origin
• Rotate moves about origin
• Flip moves about origin
• shape_set_center() moves shape such that its centre is at the specified XYZ
• shape_center() returns function capable of returning each centre coordinate

Roughly proposed behaviour:

• Scale about centre
• Rotate about centre
• Remove flip; just use rotate
• shape_set_center() to move_center() (a custom point of transformation that differs from "true" center of the shape cannot be specified)
• shape_center() to get_center()

Notes:

• A subtraction, by its nature, changes what the centre of the resulting shape is. Trying to set centre on the new solid may yield unexpected results. It could be up to the user to create higher level alignment or custom "point of transformation" abstractions by using their own calculations alongside provided functions like bounding_box()
• It could also be up to the user to implement convenience functions such as scaling on all axes by the same factor, or setting the center of one shape to that of another

[LiuMC-SG]

Refer to issues branch

[Cloud7050]

V2 + revamp:

• Scale still about origin, explained in docs
• Rotate about axes (was always the case?), explained in docs
• Flip function removed, docs mention using -1 scale for reflections
• Centre functions removed

V2 moved towards simplifying the API, resulting in quite a few removed functions. Yes they may have been nice to have (convenience/usefulness), but the user can write similar functions themselves in place of most of what has been removed.

In light of this design direction, I have opted to simply document the 3 remaining basic operations' behaviours. The user can write functions that make them more convenient to use. For example, calculating the shape centre + moving centre to origin + performing operation + moving centre back to original position.