Data types - Revision history

imported>LassiPulkkinen: /* Definitions */ Add Sound Event. This is most likely a temporary solution; would be better to have these in Registry Data.

2024-11-21T09:26:42Z

Definitions: Add Sound Event. This is most likely a temporary solution; would be better to have these in Registry Data.

@@ Line 158: / Line 158: @@
   | See [[#ID Set]] below
   | Set of registry IDs specified either inline or as a reference to a tag.
   |}
@@ Line 301: / Line 306: @@
   | {{Type|Optional}} {{Type|Array}} of {{Type|VarInt}}
   | An array of registry IDs. Only present if Type is not 0.<br>The size of the array is equal to <code>Type - 1</code>.
   |}

imported>LassiPulkkinen: /* Definitions */ Add ID or X and ID Set (these were added in 1.20.6).

2024-11-21T03:49:01Z

Definitions: Add ID or X and ID Set (these were added in 1.20.6).

@@ Line 148: / Line 148: @@
   | Depends on context
   | This is just a sequence of zero or more bytes, its meaning should be explained somewhere else, e.g. in the packet description. The length must also be known from the context.
   |}
@@ Line 248: / Line 258: @@
 The <var>i</var>th bit is set when <code>(Data[i / 8] & (1 << (i % 8))) != 0</code>, where <var>i</var> starts at 0. This encoding is ''not'' equivalent to the long array in BitSet.
 <noinclude>

imported>LassiPulkkinen: Update section on fixed-point numbers, make example more general.

2024-06-11T18:48:36Z

Update section on fixed-point numbers, make example more general.

← Older revision		Revision as of 18:48, 11 June 2024
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	<noinclude>== Fixed-point numbers ==</noinclude><includeonly>=== Fixed-point numbers ===</includeonly>		<noinclude>== Fixed-point numbers ==</noinclude><includeonly>=== Fixed-point numbers ===</includeonly>

	Some fields may be stored as [https://en.wikipedia.org/wiki/Fixed-point_arithmetic fixed-point numbers], where a certain number of bits ~~represents~~ the signed integer part (number to the left of the decimal point) and the rest ~~represents~~ the fractional part (to the right). Floating ~~points~~ (float and double), in contrast, keep the number itself (mantissa) in one chunk, while the location of the decimal point (exponent) is stored beside it.		Some fields may be stored as [https://en.wikipedia.org/wiki/Fixed-point_arithmetic fixed-point numbers], where a certain number of bits represent the signed integer part (number to the left of the decimal point) and the rest represent the fractional part (to the right). Floating point numbers (float and double), in contrast, keep the number itself (mantissa) in one chunk, while the location of the decimal point (exponent) is stored beside it. Essentially, while fixed-point numbers have lower range than floating point numbers, their fractional precision is greater for higher values.

	~~Essentially, while~~ fixed-point ~~numbers have lower range than floating points, their fractional precision is greater for higher values~~. ~~This makes them ideal for representing global coordinates~~ of ~~an entity~~ in ~~Minecraft~~, ~~as it's more important to store the integer part accurately than position them more precisely within a single block (or meter)~~.		Prior to version 1.9 a fixed-point format with 5 fraction bits and 27 integer bits was used to send entity positions to the client. Some uses of fixed point remain in modern versions, but they differ from that format.

	~~Coordinates are often represented~~ as a 32-~~bit~~ integer~~, where 5 of the least-significant~~ bits ~~are dedicated to the fractional part, and the rest store the integer part.~~		Most programming languages lack support for fractional integers directly, but you can represent them as integers. The following C or Java-like pseudocode converts a double to a fixed-point integer with <var>n</var> fraction bits:

			x_fixed = (int)(x_double * (1 << n));

	~~Java lacks support for fractional integers directly, but you can represent them as integers. To convert from a double to this integer representation, use the following formulas:~~
	~~abs_int = (int) (double * 32.0D);~~
	And back again:		And back again:

	~~double~~ = (double) (~~abs_int / 32.0D~~);		x_double = (double)x_fixed / (1 << n);

	<noinclude>== Bit sets ==</noinclude><includeonly>=== Bit sets ===</includeonly>		<noinclude>== Bit sets ==</noinclude><includeonly>=== Bit sets ===</includeonly>

imported>LassiPulkkinen: /* Definitions */ Note about mismatched length limits for JSON Text Component.

2024-06-11T17:52:41Z

Definitions: Note about mismatched length limits for JSON Text Component.

← Older revision		Revision as of 17:52, 11 June 2024
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	\| ≥ 1 <br />≤ (262144×3) + 3		\| ≥ 1 <br />≤ (262144×3) + 3
	\| See [[Text formatting#Text components]]		\| See [[Text formatting#Text components]]
	\| ~~Encoded as a String with max~~ length of 262144.		\| The maximum permitted length when decoding is 262144, but the Notchian server since 1.20.3 refuses to encode longer than 32767. This may be a bug.
	\|-		\|-
	! id=Type:Identifier \| {{Type\|Identifier}}		! id=Type:Identifier \| {{Type\|Identifier}}

imported>LassiPulkkinen: The array returned by BitSet.toByteArray is only as long as necessary to represent the bits, so at risk of stating the obvious, specify that it should be padded.

2024-06-11T17:36:58Z

The array returned by BitSet.toByteArray is only as long as necessary to represent the bits, so at risk of stating the obvious, specify that it should be padded.

← Older revision		Revision as of 17:36, 11 June 2024
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	\| Data		\| Data
	\| {{Type\|Byte Array}} (n)		\| {{Type\|Byte Array}} (n)
	\| A packed representation of the bit set as created by [https://docs.oracle.com/javase/8/docs/api/java/util/BitSet.html#toByteArray-- <code>BitSet.toByteArray</code>].		\| A packed representation of the bit set as created by [https://docs.oracle.com/javase/8/docs/api/java/util/BitSet.html#toByteArray-- <code>BitSet.toByteArray</code>], padded with zeroes at the end to fit the specified length.
	\|}		\|}

imported>TheAIguy: Changed Fixed BitSet size

2024-06-11T14:53:43Z

Changed Fixed BitSet size

← Older revision		Revision as of 14:53, 11 June 2024
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	\|-		\|-
	! id=Type:Fixed_BitSet \| {{Type\|Fixed BitSet}} (n)		! id=Type:Fixed_BitSet \| {{Type\|Fixed BitSet}} (n)
	\| n		\| ceil(n / 8)
	\| See [[#Fixed BitSet]] below		\| See [[#Fixed BitSet]] below
	\| A bit set with a fixed length of <var>n</var> bits.		\| A bit set with a fixed length of <var>n</var> bits.

imported>WinX64: Fixed BitSets are defined by the number of bits, not bytes

2024-03-13T18:52:26Z

Fixed BitSets are defined by the number of bits, not bytes

← Older revision		Revision as of 18:52, 13 March 2024
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	\| n		\| n
	\| See [[#Fixed BitSet]] below		\| See [[#Fixed BitSet]] below
	\| A bit set with a fixed length of <var>n</var> ~~bytes~~.		\| A bit set with a fixed length of <var>n</var> bits.
	\|-		\|-
	! id=Type:Optional \| {{Type\|Optional}} X		! id=Type:Optional \| {{Type\|Optional}} X
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	<noinclude>=== Fixed BitSet ===</noinclude><includeonly>==== Fixed BitSet ====</includeonly>		<noinclude>=== Fixed BitSet ===</noinclude><includeonly>==== Fixed BitSet ====</includeonly>

	Bit sets of type Fixed BitSet (n) have a fixed length of <var>n</var> bytes. Note that this is different from BitSet, which uses longs.		Bit sets of type Fixed BitSet (n) have a fixed length of <var>n</var> bits, encoded as <code>ceil(n / 8)</code> bytes. Note that this is different from BitSet, which uses longs.

	{\| class="wikitable"		{\| class="wikitable"

imported>WinX64: /* Definitions */ Both cases use nameless tags, as does the entire rest of the protocol

2024-03-11T13:46:57Z

Definitions: Both cases use nameless tags, as does the entire rest of the protocol

← Older revision		Revision as of 13:46, 11 March 2024
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	\| See [[Text formatting#Text components]]		\| See [[Text formatting#Text components]]
	\| Encoded as a [[NBT\|NBT Tag]], with the type of tag used depending on the case:		\| Encoded as a [[NBT\|NBT Tag]], with the type of tag used depending on the case:
	* As a ~~nameless~~ [[NBT#Specification:string_tag\|String Tag]]: For components only containing text (no styling, no events etc.).		* As a [[NBT#Specification:string_tag\|String Tag]]: For components only containing text (no styling, no events etc.).
	* As a [[NBT#Specification:compound_tag\|Compound Tag]]: Every other case.		* As a [[NBT#Specification:compound_tag\|Compound Tag]]: Every other case.
	\|-		\|-

imported>LassiPulkkinen: Use Template:Type for type links. Rename typedef anchors to make the template actually work. Rename NBT Tag -> NBT. (Last round of bikeshedding, I swear!)

2024-02-24T21:41:15Z

Use Template:Type for type links. Rename typedef anchors to make the template actually work. Rename NBT Tag -> NBT. (Last round of bikeshedding, I swear!)

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imported>LassiPulkkinen: Move Particles section to Particles.

2024-02-24T04:45:44Z

Move Particles section to Particles.

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