Make a new Sprite.hit_box match the sprite right away

[pvcraven]

Summary

Fixes the Sprite.hit_box setter, which I noted earlier while working on collisions.

The problem

The setter kept the given hit box's own position and scale. For a new HitBox(points), those are (0, 0) and 1. For a HitBox, it copied only the sprite's angle; a RotatableHitBox was used exactly as given. For a sprite at (100, 100) with scale 2:

After sprite.hit_box = HitBox(points)	Before	After
Hit box position	(0, 0)	(100, 100)
Hit box scale	1	2
Collides with a sprite in the same spot	no	yes
Spatial hash finds a bigger hit box	no	yes

So a sprite with a custom hit box collided with nothing until it moved. Even then, the hit box kept a scale of 1 until the sprite was scaled. A spatial hash also kept using the old hit box's size.

The fix

The setter now gives the hit box the sprite's position, scale and angle, for HitBox and RotatableHitBox alike, and updates the spatial hash. The docstring now says that the points are relative to the sprite's center, and that the hit box's own position, scale and angle are replaced.

The three places in Arcade that set hit_box already passed the sprite's own position, angle and scale: Sprite.texture, Sprite.sync_hit_box_to_texture() and the tile map loader. So their behavior doesn't change.

Tests

New in tests/unit/sprite/test_sprite_hitbox.py:

• test_set_hit_box_matches_sprite: right after setting, the position, scale and angle match the sprite, and so do the adjusted points (rotated 90°, scaled by 2, moved).
• test_set_rotatable_hit_box_matches_sprite: a RotatableHitBox's own position, scale and angle are replaced.
• test_set_hit_box_follows_sprite_afterwards.
• test_set_hit_box_collides_right_away.
• test_set_hit_box_updates_spatial_hash.

4 of them fail on development. The "follows afterwards" one already passed and guards that behavior. I also updated a comment in a sweep test that described the old behavior as a workaround.

Full suite: 1588 passed, no warnings, with no failures on my machine now that #2926 is in. Ruff is clean, and mypy has no new errors.

The changelog has an entry under Unreleased → Fixes.

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