Right now the objects are hidden when they are not active, and they only appear when they are activated (by being triggered and by the timestamp).
But sometimes it's useful for it to be the other way around, and disappear when activated.

For example, it would be fun to make it so that the whole map starts disappearing as soon as you pick up some object and you have to run for your life to avoid sinking in the lava.

Another use for this would be for an object to disappear on activation when the player touches it (or gets close to it), as if it was an object that was picked up. We would need no more keys or apples to trigger events, we could make our own custom buttons and item-like objects this way.

I second this idea, it seems like a really good feature to implement, although being able to just create or re-skin items would work as well.

Scenery objects are stamped into terrain space when they are created, so they can't simply be removed again. Zep has mentioned adding delete boxes which would clear a space away, however.

Thinking about it now, perhaps the simplest/most flexible way is to be able to set a flag on an object that made it an "anti-object", so when it was created, instead of adding pixels from the bottom up, it deletes pixels in the shape of itself, from the top down. So anywhere on the object there is a pixel, in the world is created an empty space.

This way, not only could you create a duplicate "anti-object" over any object you want to make disappear, but you could also do other things, like carve out arbitrarily-shaped holes, or slice out a layer of pixels to make an object collapse.

I've been hesitant to post this suggestion, since the forums are already flooding with ideas, but I agree, this would be an excellent feature for the game. I also agree that using 'delete boxes' would likely be a good way to think about this for now, Anthony.

However, I'm not a developer. =]

Did I say pixels?

I MEAN VOXELS

Yeah id like this function to make closed doors open