@heinezen can I take this

Sure, I think there's currently nothing blocking this feature.

So will this be an array of KeyframeContainers , essentially?

Yeah that's basically it.

Should I use something other than KeyframeContainers, queue and map don't seem to use it.

For the array curve, KeyframeContainers are fine because the size of the array is fixed, so all elements exist with a value over the duration of the array's existance. For the other containers, elements are not guaranteed to always be persistent. They can get erased and later added again, which has to be accounted for (that's why there's this dead/alive logic for their keyframes).

So for the iterator, do we iterate over keyframes with the closest time less than or equal to t?

Yes, when iterating over the array at time t, it should iterate over the elements that are valid at time t

So the result should be the same as calling all the indices individually for the same time: get(t, 0) ... get(t, n)

No erase method?

The array would have a fixed size from the start for the duration of its lifetime, so removing elements wouldn't make sense.

What about removing elements from keyframecontainers?

Is there a specific example where removing keyframes would be necessary? It's not used by any other curve. If we need it in the future, we could always add it, but I don't think it belongs to the public API of a curve array.

BaseCurve has an erase method, which is public.

@jere8184 Hmm... I think we could add it then. Certainly wouldn't hurt!

How should the iterator handle KeyframeContainers that contain multiple keyframes for a given time? currently, we just iterate over a single valid keyframe for each container.

@jere8184 In that case, the last frame that was inserted (as in: by insertion order) for that time should be used.

So I've implemented the array curve using KeyframeContainers this differs from the other Container curves (queue and map) as they store their elements in element_wrappers this difference was supposedly because we will not erase Keyframes from the array right?

For the array curve, KeyframeContainers are fine because the size of the array is fixed, so all elements exist with a value over the duration of the array's existance. For the other containers, elements are not guaranteed to always be persistent. They can get erased and later added again, which has to be accounted for (that's why there's this dead/alive logic for their keyframes).

I'm just making sure I understand correctly before updating the curve documentation file.

Where does the idea that we shouldn't erase keyframes from array come from?

Where does the idea that we shouldn't erase keyframes from array come from?

I think that's more a misunderstanding. My point was that elements shouldn't be erased for arrays (in comparison to maps/quues), since the array always has a fixed size. Removing keyframes from specific containers is okay, it's just not a very common operation.