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This category consists of posts which form “1st beta” of the Vol.I-III of the upcoming book “Development & Deployment of Multiplayer Online Games”. Please note that “2nd beta” (available on Indiegogo) has 75% of the new content compared to the “1st beta” (in particular, based on the comments here on ithare.com and on /r/programming), so please don’t hit me too hard for the quality of the “1st beta”. ToC of “2nd beta”.

D&D of MOGs: Vol I-III (1st beta), page 1:

Scalability for MOGs

Quote: “Whenever Game Event is interrupted for significant time, as a rule of thumb it is better to roll back the interrupted Game Event rather than trying to restore the exact Game World State in the middle of the Game Event.”
Another Quote: “Just like Scaling Up, improving performance doesn’t provide infinite scalability. However, it happens that it is all about numbers.”

Pre-Coding Checklist: Things Everybody Hates, but Everybody Needs Them Too. From Source Control to Coding Guidelines

Quote: “The basic idea behind Continuous Integration is simple: as soon as you commit something, a build is automatically run with all the tests you were able to invent by that time”
Another Quote: “One thing which should be noted about agile criticisms, is that there is no real disagreement about what needs to be done; the sentiment in such criticisms is usually more along the lines of “we’re doing it anyway, so do we need fancy names and external consultants?””

Unity 5 vs UE4 vs Photon vs DIY for MMO

Quote: “You can still use HLAPI despite its shortcomings”
Another Quote: “If you’re using one of the engines above (and not your own one), and your game requires Client-Driven Development Flow, you may want to start with a single-player Unity 5, or with a single-player UE4.”

IDL: Encodings, Mappings, and Backward Compatibility

Quote: “Modifying generated code usually qualifies as a Really Bad Idea”
Another Quote: “How much can be gained by each of such specialized encodings – still depends on the game, but if you can try-and-test a dozen of different encodings within a few hours – it will usually allow you to learn quite a few things about your traffic (and to optimize things both visually and traffic-wise too).”

MMOG. Point-to-Point Communications and non-blocking RPCs

Quote: “In other words, you can write your code ‘as if’ all-your-code-within-the-same-FSM executed within the same thread”
Another Quote: “As soon as we have these two parts of processing – we can say that our Server-to-Server communication is tolerant to all kinds of transient inter-server disconnects”

MMOG: World States and Reducing Traffic

Quote: “In practice, for most classical RPGs you can get away with simulating each of your PCs and NPCs as a box (parallelepiped), or as prism (say, hexagonal or octagonal one)”
Another Quote: “Mathematically speaking, without Interest Management, the amount of data on our servers will need to send (to all players combined), is O(N^2). Interest Management reduces this number to O(N)”

MMOG. RTT, Input Lag, and How to Mitigate Them

Quote: “For fast-paced games, there is one big problem with the flow shown on this diagram, and the name of the problem is “latency” (a.k.a. ‘input lag’)”
Another Quote: “No, better bandwidth doesn’t necessarily mean better latency”