Since circles are just special cases of ellipses where both half width
and half height are equal to the radius, this is an easy generalization.

- Added capabilities to draw ellipses
- all previously existing circle drawing mechanisms are derived from
  ellipses now

Authored-by: RobWalt <robwalter96@gmail.com>

implement the first few drawing methods for primitives on `Gizmos`

Authored-by: RobWalt <robwalter96@gmail.com>

Authored-by: RobWalt <robwalter96@gmail.com>

(non-optimal?)

Authored-by: RobWalt <robwalter96@gmail.com>

- added docs to all the new traits and structs
- manually tested whether the visuals were ok
- refactored the code a bit to prevent duplication
- improved visuals of arc like parts (probably add 3D arc to gizmo in a
  follow up commit)

Authored-by: RobWalt <robwalter96@gmail.com>

To ease the use of all the primitive details structs needed for
rendering, implement `Default` for them.

For some values it's kind of hard to pick good defaults. I tried to use
values that'll hopefully work better with respect to performance.

Authored-by: RobWalt <robwalter96@gmail.com>

Authored-by: RobWalt <robwalter96@gmail.com>

The new arc approach uses the same API as unity does

https://docs.unity3d.com/ScriptReference/Handles.DrawWireArc.html

This gets rid of the restriction of only drawing arcs with angles
smaller than 180 degrees which was previously the case.

This new arc3d API might also be included into the standard gizmos arc
module.

Authored-by: RobWalt <robwalter96@gmail.com>

A lot of the 3D primitives share similar base shapes in 3D. This commit
factors out those base shapes into functions for easier reuse.

Authored-by: RobWalt <robwalter96@gmail.com>

- Remove notes and add new note about optimization which needs consensus
- Implement minor circles of torus via four arcs to prevent weird
  rotation of minor circles

Authored-by: RobWalt <robwalter96@gmail.com>

This commit implements the visualization of various 3d primitives. You
can scroll through them with the UP/DOWN keys and for the ones that use
segments for level of details you can increase/decrease precision with
M/N keys.

Authored-by: RobWalt <robwalter96@gmail.com>

Use builder pattern that already exists for arcs and circles instead of
extra details structs for supplying the details of the primitives.

Authored-by: RobWalt <robwalter96@gmail.com>

Also implement the builder pattern for all 3D primitives. As it turns
out, this approach doesn't really work yet due to lifetime bounds.

Authored-by: RobWalt <robwalter96@gmail.com>

So many thanks to nothy for helping me with the lifetimes ♥️

Authored-by: RobWalt <robwalter96@gmail.com>
Co-Authored-by: nothendev <borodinov.ilya@gmail.com>

Authored-by: RobWalt <robwalter96@gmail.com>

Authored-by: RobWalt <robwalter96@gmail.com>

I noticed some flaws with the original implementation of the API while
creating some examples:

- The orientation via `from` and `rotation_axis` fields felt really
  wonky
- The rotation seemed not to rotate around the center set by the user

This is why I reimplemented the API. It now draws some kind of default
arc in 3D which has properties which are documented in the doc strings.
You can modify this default arc via builder methods which seems to be
the most flexible approach in my eyes.

Authored-by: RobWalt <robwalter96@gmail.com>

Authored-by: RobWalt <robwalter96@gmail.com>

and also adjust:

- docs
- tests
- examples

Authored-by: RobWalt <robwalter96@gmail.com>

Authored-by: RobWalt <robwalter96@gmail.com>

This includes:

- remove builders for mandatory arguments
- refactor the API to look more similar to the rest of the gizmo APIs
- split primitives module into 2d and 3d

Thanks for the thorough review Jondolf!

Authored-by: RobWalt <robwalter96@gmail.com>

Authored-by: RobWalt <robwalter96@gmail.com>

Authored-by: RobWalt <robwalter96@gmail.com>

Authored-by: RobWalt <robwalter96@gmail.com>

Authored-by: RobWalt <robwalter96@gmail.com>

Fix code after rebasing on main. The capsule primitive was split for 2d
and 3d cases.

Authored-by: RobWalt <robwalter96@gmail.com>

This includes:

- just drawing one line for line segements (2D/3D)
- use minimum length for directions in 2D to prevent 1 pixel lines
  - now: 50 pixel
- changing the infinit-ness of lines by adding big constant scale
  factors now:
  - 2D infinite length: 100_000
  - 3D infinite length: 10_000
- refactor plane (2D/3D) to use other primitives for simplicity and less
  repetition (they now use a combination of Direction + Segement
  rendering)
- add configurable options to Plane3d (number + detail + size of hinting axis)
- adjust examples in 2D/3D cases
- use consistent variable names
- clean up docs

Authored-by: RobWalt <robwalter96@gmail.com>

Authored-by: RobWalt <robwalter96@gmail.com>

The examples should probably be cleaner than the previous state. After
all people are learning with these so we should implement best practices
and keep systems small and decoupled.

Authored-by: RobWalt <robwalter96@gmail.com>

This commit implements a loose bunch of small polishing fixes:

- use angles in radians instead of `Mat2` for rotation in 2D primitive
  case and ellipse case
- use constants on `Direction2D` struct as much as possible
- update key bindings in examples to be consistent
- update user facing text in examples to reflect real key bindings
- fix naming on configurating builder for `Plane3D`

sorry should have added you earlier below 🙈

Reviewed-by: Joona Aalto <jondolf.dev@gmail.com>
Authored-by: RobWalt <robwalter96@gmail.com>

Since a `half_size` `Vec2` was used on a lot of primitives lately I
thought that we should be consistent here with ellipses as well.

Authored-by: RobWalt <robwalter96@gmail.com>

Authored-by: RobWalt <robwalter96@gmail.com>

Authored-by: RobWalt <robwalter96@gmail.com>

Authored-by: RobWalt <robwalter96@gmail.com>

Authored-by: RobWalt <robwalter96@gmail.com>

Authored-by: RobWalt <robwalter96@gmail.com>

Authored-by: Aviac <aviac@mailbox.org>