Make items bob

[nwinter]

Items, like health potions and swords and such, are currently kind of boring: they just sit on the ground. Lame. What instead they should do is what the Coins and Gems do: bob up and down in the air. But it'd be best to not have to embed a bobbing animation in each ThangType we intend to use with the inventory.Collectable Component.

Instead we should do something like what the WizardSprite does and make the bobbing happen automatically in the updatePosition method of any CocoSprite with thang.isCollectable == true.

Once that started working, we could remove the built-in bobbing animation from Coin and Gem, too.

After that's working, we'd probably want to not tie bobbing to the inventory.Collectable Component, but instead to make a new Component: display.Bobs or something like that. That would be nice, because then we could attach it to any flying Thangs, and we could remove the special-case code from the WizardSprite, too. All that display.Bobs would need to do is attach a bobs or maybe bobsUpAndDown property to the Thang, and the CocoSprite would read that instead of isCollectable. If we really wanted, we could configure the bob distance in that Component.

[nwinter]

Perfect--thanks Tom!

[nwinter]

Now I just need to update the existing items to use it.