Alpha Map Format - Revision history

imported>SirCmpwn: moved Map Format to Alpha Map Format: Outdated

2012-03-27T20:21:09Z

moved Map Format to Alpha Map Format: Outdated

@@ Line 62: / Line 62: @@
 <source lang=csharp>
 public static string Base36Encode(long input)
+{
-	         if (input == 0){ return "0"; }
+	if (input == 0){ return "0"; }
-	         string chars = "0123456789abcdefghijklmnopqrstuvwxyz";
+	string chars = "0123456789abcdefghijklmnopqrstuvwxyz";
-	         bool negative = (input < 0);
+	bool negative = (input < 0);
-		 StringBuilder sb = new StringBuilder();
+	StringBuilder sb = new StringBuilder();
-			if (negative) {
+	if (negative) {
-				input = -input;
+		input = -input;
-				sb.Append("-");
+		sb.Append("-");
+	}
-			while (input > 0) {
+	while (input > 0) {
-				sb.Insert((negative ? 1 : 0), chars[(int)(input % 36)]);
+		sb.Insert((negative ? 1 : 0), chars[(int)(input % 36)]);
-				input /= 36;
+		input /= 36;
+	}
-			return sb.ToString();
+	return sb.ToString();
+}
 </source>
@@ Line 84: / Line 84: @@
 Persistent data for players is stored in a folder called "players". Each player has a file called "<username>.dat".
 {| class="wikitable"
@@ Line 101: / Line 168: @@
 Two-dimensional noise functions can be used to provide a terrain height at certain coordinates.
-[[Category:Minecraft Alpha]]
+[[Category:Minecraft Beta]]
 [[Category:File Formats]]

imported>Xinnx: /* The Base-36 Algorithm */

2011-03-02T13:28:53Z

The Base-36 Algorithm

@@ Line 56: / Line 56: @@
           s = "-" + s
       return s
 = Players =

imported>SpaceManiac: Categorizing

2010-12-19T18:04:52Z

Categorizing

New page

Alpha worlds consist of several files, all held together in one folder under a very rigid directory structure.

= Level =

The level is a file called "level.dat" in the root of the world.

{| class="wikitable"
! Name || Type || Description
|-
| Data || Compound || General level data
{| class="wikitable"
! Name || Type || Description
|-
| RandomSeed || Long || The seed of the world, which is used to generate new geometry.
|-
| SpawnX || Int || The X coordinate of the default spawn point
|-
| SpawnY || Int || The Y coordinate of the default spawn point
|-
| SpawnZ || Int || The Z coordinate of the default spawn point
|}
|}

= Chunks =

Chunks are stored in folders inside the world corresponding to their coordinates in base-36. The path is "<base-36-x-63>/<base-36-z-63>/c.<base-36-x>.<base-36-z>.dat", where <base-36-x-63> is the base-36 representation of the X coordinate of the chunk AND'd bitwise with 63.

For example, if we have the chunk coordinate (39, -13), we end up with the path 13/1f/c.13.-d.dat

The main world is stored in the root directory of the world. The Nether is stored in the "DIM-1" folder in the root and uses the same chunk folder system.

== The Base-36 Algorithm ==

To retrieve the base-36 representation of a number, use the digits "0123456789abcdefghijklmnopqrstuvwxyz", and prefix the result with a hyphen ("-") if the number is negative.

Example code in Python, from [[Beta]]:

def base36(i):
"""
Return the string representation of i in base 36, using lowercase letters.
"""
letters = "0123456789abcdefghijklmnopqrstuvwxyz"
if i < 0:
i = -i
signed = True
elif i == 0:
return "0"
else:
signed = False
s = ""
while i:
i, digit = divmod(i, 36)
s = letters[digit] + s
if signed:
s = "-" + s
return s

= Players =

Persistent data for players is stored in a folder called "players". Each player has a file called "<username>.dat".

{| class="wikitable"
! Name || Type || Description
|-
| Pos || List of 3 doubles || X, Y, and Z coordinates of the player position, in pixel coordinates
|-
| Rotation || List of 2 doubles || Yaw and pitch of the player, in degrees
|}

= Map Generation =

There are several approaches to map generation.

== Noise ==

Two-dimensional noise functions can be used to provide a terrain height at certain coordinates.

[[Category:Minecraft Alpha]]
[[Category:File Formats]]