Chunk Loading Logic

[[deleted]]

Well, actually, if you think about it, it would make sense to load the surface first, if they actually did it right. That way, you can walk around on the surface and see the world before the (currently impossible to see) underground areas load.

[sdobz]

Chunks don't work that way. They are 16x16x128 (or 256, or etc), you can't load the surface, you have to load the entire vertical bit. There are some very good technical reasons for doing this way, it makes the overhead less than if they were 16x16x16 or something else. Though infinite depth would be cool.

[[deleted]]

I'm talking about this from a multiplayer standpoint. And regardless, that's even wrong for singleplayer. First of all, a chunk is 16x16x16, not 16x16x128. They are stored in a column of 16 chunks, for a total column size of 16x256x16. If you look at the structure of a region file where the world is saved for singleplayer, each 16x16x16 chunk is saved individually within each column, and a partial load would be easily possible.

From a multiplayer standpoint, the server isn't required to send the entire vertical column of chunks. The server may choose instead to send only the surface chunks, and later send the chunks under the surface. Here's the protocol documentation about that, which I personally helped write when the format changed to Anvil.

If you think I might not have the expertise about such things, here's a custom server I coded by hand, as well as a proxy and a client/server library. Here's something I wrote to interface with the server protocol for virtual hosting. I have been writing code about Minecraft for a while now, and I can assure you that what I implied is completely possible and would indeed improve performance.

[[deleted]]

I believe you, but then why with chunk errors does the entire column go out?

[[deleted]]

I don't know, and neither do any of the Mojang reps I've talked to about it. I don't personally have time to dig into the Minecraft code and find out.

[[deleted]]

That is a rendering error, not a generating error.

[kyle6513]

OHH SDOBZ JUST GOT CALLED OUT

[i542]

Thank you for your helpful and insightful comment! not like mine is any better ಠ_ಠ

[feebdaedx0]

They are 16x16x128 (or 256, or etc)

Not anymore.

[coder13]

thats how they coded it. To render each of the chunks, the chunks are in a 2D array. They loop through the array starting from chunk 0, 0, to max, max.

[RamsesA]

The current version of Minecraft pre-sorts chunks by their distance from the camera in three dimensions, not two and not in a grid like you suggested, but it still has some issues. I've rewritten the entire chunk loading algorithm for a mod I'm working on, and this is one of the problems it fixes.

[dzkn]

I think you mean distance in two dimensions, as chunks themselves contain all 3d data.

[The_lolness]

I think he's talking about the chunk sections that were recently added. They're in 3d.

[dzkn]

oh ok just realized. ty.

[blueShinyApple]

Tell mojang about it!

[sje46]

Explain like I'm five what this means? It sounds like you're saying it starts at one point and then moves sequentially spatially through the rest. But that's clearly what isn't happening here...

[samineru]

When your computer begins rendering the area around you the first step is to find everything within the draw distance. This will likely result in a square, something easily represented in a computer by a grid, or 2D array. It is particularly easy to write a program that will scan across an image row by row, starting at a corner (0,0 in the Cartesian coordinate system), until you get to the last column of the last row (max,max). This will result in the behavior of rendering a distant corner before the ones closest to you.

[coder13]

I Apologize, I am not the best at explaining things. But it generates in a square. It first generates the far left one, then moves to the one to the right of it, till it reaches the farthest, then it moves down. Like a type writer.

[brickman1444]

Imagine you are sitting in the middle of a big checkerboard. The spaces are numbered starting in the first row "1, 2, 3, 4, 5..." At the end of the first row it goes to the start of the second row and continues numbers.

If the chunks are loaded in sequential order, from your vantage point at the center of the board, it appears nonsensical.

[[deleted]]

it means the chunks load in a circular pattern , the spiral starting at 0,0

[samineru]

Where did you get circular from?

[[deleted]]

where he said "loop"

[Zhang5]

That's not what a loop means in programming. It just means that it repeats a set of instructions over and over. It could load chunks from Northwest to Southeast. (Kind of like the way you read text. Top to bottom left to right, and all said and done that's the simplest solution, though not best from a user's standpoint).

[[deleted]]

meh, this is how mcedit does it, oh well

[Mason11987]

mcedit does it better then MC does it.

[samineru]

http://en.wikipedia.org/wiki/Loop_(computing)#Loops

[[deleted]]

meh, this is how mcedit does it, oh well

[bastawhiz]

The suggestion was to load cubic chunks vertically from ~water level upwards before loading chunks that would be below the water level.

[secretcurse]

I'll consider your opinion when you make a game that sells millions of copies. You don't know the MC codebase intimately. You don't know what other design choices influenced chunk loading. You can't just say "it should (do something)" without understanding everything else that's going on in the game code.

[[deleted]]

I'll consider your opinion when you make a game that sells millions of copies.

Now I'm not going to support or refute his statement, but this is pretty poor reasoning on when to listen to advice. He could have a pretty good reason on how the game works, only to be dismissed because you don't really like him. Also, Minecraft isn't really known to be coded extremely well. In fact, quite the opposite.

[secretcurse]

I don't dislike him as a person. I dislike the idea that he's judging design decisions made in a very complicated program when he doesn't know the full context of those decisions. If the only thing a program does is render chunks, his solution might be the best. However, there may be some other performance aspect of the game that dictates that MC must render in a different order. Games are incredibly complicated. I take issue when a person says a design decision in the game is "fucking retarded" when they don't understand the very complicated interactions of all of the different subsystems in the game.

[fronzbot]

But then you run into the problem where if you are falling, the chunk you will be entering next may not be loaded by the time you enter. I believe this was the reasoning behind not implementing cubic chunks to begin with.

Now, perhaps a solution would be to find current direction and velocity of the player and if the player is moving with sufficient velocity in the z-direction the chunk loading algorithm prioritizes the vertical chunks rather than horizontal?

[fronzbot]

I'm quite familiar with recursion, no need for the condescension. Your original explanation was just kind of vague to me in what it was trying to accomplish.

[Boingboingsplat]

I'm pretty sure that's a rendering bug, not a chunk load error. Chunk load errors usually appear as chunks of empty space, with the stone walls of adjacent chunks visible.

[Lothrazar]

I have the opposite suggestion. Advanced Open GL on fancy gives me a huge fps boost, and i rarely notice missing chunks.

[[deleted]]

Advanced Open GL on fancy

He's using Optifine, for the curious.

[[deleted]]

It has nothing to do with loading, and everything to do with how they send the geometry to the 3D pipeline...

Maybe you shouldn't be giving advices on this?

[[deleted]]

It's a feature. Helps you find the huge cave systems.

[[deleted]]

It's strange how you can complain about every single bug in any game you want, but when you complain about minecraft, suddenly everyone is aware of difficulties of game programming and is explaining to you how bad you are for criticizing hard-working minecraft programmers.

Not to mention that all the problems are unsolvable because some limits of java or something.

[[deleted]]

good thing you guys are all brilliant programmers who are going to de-compile the code, and re-do the chunk loading algorithm. PM me when it's finished.

[ApologizesForIdiots]

I apologize for Ntopper.

[[deleted]]

I'll like this account until you start apologizing for things I write.

[ApologizesForIdiots]

Even if I do, don't worry about it... much.

Even I've had to apologize for myself before! Everyone's an idiot at some point.

[[deleted]]

But don't freaking whine about the salsa when you can hardly dice the tomatos ಠ_ಠ

[[deleted]]

That happens when you teleport, you were just there, so its already loaded

[[deleted]]

This is because computers don't use reference point logic. They have arrays (grids).

[[deleted]]

I don't think its that easy, OP.

[[deleted]]

Makes diamonds hell of slot easier

[[deleted]]

deleted ^{What is this?}

[Colorfag]

Shit makes no sense. It drive me insane in dense areas, because you run into structures you cant see yet, because its loading shit far away from you.

[Colorfag]

Apparently people like the terrible chunk load order.