I'm pinging the dev community collective to determine whether there is an official name for the behaviour I'm looking to build.

Let's say there's client C, spatially positioned at 0,0. C initially has access to data points immediately around him in 8 'chunks', as well as the 'chunk' which matches his position, for a 'chunk' payload of 3x3. If we converted these to an arbitrary cartesian system, we could assume the chunks are 10x10 units, thus C's access to data points ranging from (-15,-15) to (+15,+15).

If C moves along the positive X axis 10 units, then the three chunks furthest from him on the X axis are discarded from memory, three new chunks are loaded from a data source, and C now has access to data points ranging from (-5,-15) to (25,15).

A chunk's size is typically static, however some games present 3x3 chunking for data management whereas others present more, or variable number of chunks. What is key here is the minimum is 3x3, the client is always located in the center chunk, and the number of chunks is usually odd.

This sort of data access traces back to the dark ages of computer gaming as found in titles such as early Ultimas (at least IV, probably earlier), more recently in games like (likely) Minecraft.

I'm curious to know if there is an official name for this sort of "progressive chunked data-point loading", and if so, what is it called? :-) I'm building a game which uses spatial data, and if I can avoid reinventing the wheel, I'd like to. I just don't know what the official name would be for this sort of thing.

(Incidentally, I've read up on BSP Trees, Octrees, Bounding Volume Hierarchies and Quad-trees, but I don't think they apply here.)

• Why should one name something like calculating the nearest neighbor by adding +-1 combinations to the x-/y-coordinates? That's plain too trivial. – qwerty_so Nov 21 '16 at 6:41
• The game concept (a unit only has a finite radius of visibility) is "fog of war". When implemented in software it can be called many different names, but a very intuitive one is "sliding window" which is a term used outside computer science - economics, finance, statistics, etc. Note that "I think it must be new, therefore it must not have been given a name yet" is a fallacy. The 2D spatial search data structures are used to implement the effect. – rwong Nov 21 '16 at 7:04
• It is widely understood that when implementing sliding window methods, one can "add" the new cells which enter the sliding window, and "remove" the old cells which have exited the sliding window. This technique is exploited in image processing, for example search for 2D median filtering algorithms. – rwong Nov 21 '16 at 7:09
• If it retains some of the data from a previous location, then there is a cache, so it makes a sliding window cache. – rwong Nov 21 '16 at 23:03
• @ThomasKilian Perhaps re-read my question, and revise your answer. The closest term to what I'm looking for is, thanks to rwong, sliding window. – sws Nov 22 '16 at 1:46