center_x and center_y do not update when changing a Sprite's texture to one of a different size

[DigiDuncan]

Bug Report

Actual behavior:

See title.

Expected behavior:

The center_x and center_y should reflect the new positioning due to its texture changing.

Steps to reproduce/example code:

1. Create a Sprite with a Texture.
2. Check it's center_x and center_y.
3. Update its Texture to one of a different size.
4. Observe no change to the Sprite's center_x and center_y properties.

b = sprite.bottom
sprite.set_texture(1)  # different size
sprite.bottom = b  # does nothing, even though the size is different

[einarf]

What there anything related to collision what prevented us from updatding this? I know several people have commented on this issue before, but I don't really know the implications of doing this change.

[pvcraven]

We didn't update the hitbox because changing a texture could cause the hitbox to update such that the sprite would now be colliding with a wall. The physics engine at the time was terrible, and if it suddenly found a player in a wall it would teleport her any-which-way to get her out. Now the engine is only slightly less primitive, and it more likely to 'guess' a better collision resolution, but it still isn't great.

[DigiDuncan]

Would it be possible to have a update_hitbox() I could call after changing the texture, such that I could then set .bottom and it actually reflect the new size of the Texture? I'm struggling to get it to work like I'd like in pure code without that and my game doesn't use collision detection.

[pvcraven]

You can update the hitbox yourself:

my_sprite.hit_box = my_texture.hit_box_points

[pvcraven]

I'm thinking this will not change, other than the doc updates. At some point in the future we might support adding a baseline, or whatever it is like Unity does, where we change the center.

[einarf]

At the very least we should offer some method to re-center the sprite just like we have for syncing the hit box with the current texture. Moved to 3.x.x so it doesn't disappear in the void.