RNG - Revision history

AgentMuffin at 17:53, 27 May 2026

2026-05-27T17:53:06Z

← Older revision		Revision as of 17:53, 27 May 2026
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	\|~~style="background:#9EFF9E;"~~\|1		\|{{Yes\|1}}
	\|style="background:#9EFF9E;border-left-width:2px;"\|1		\|style="background:#9EFF9E;border-left-width:2px;"\|1
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	\|~~style="background:#9EFF9E;"~~\|1		\|{{Yes\|1}}
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	\|style="background:#9EFF9E;border-left-width:2px;"\|1		\|style="background:#9EFF9E;border-left-width:2px;"\|1
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	\|~~style="background:#9EFF9E;"~~\|1		\|{{Yes\|1}}
	\|~~style="background:#9EFF9E;"~~\|1		\|{{Yes\|1}}
	\|style="border-left-width:2px;"\|0		\|style="border-left-width:2px;"\|0
	\|}		\|}

Nim: lol

2026-04-16T03:23:55Z

lol

← Older revision		Revision as of 03:23, 16 April 2026
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	===Properties===		===Properties===
	[[File:RNG Graph.png\|500px\|thumb\|A graph showing notable RNG values and indices in SM64.]]		[[File:RNG Graph.png\|500px\|thumb\|A graph showing notable RNG values and indices in SM64.]]
	The RNG function has 65536 possible inputs and 65536 possible outputs. ~~It is a [[wikipedia:Bijection\|bijection]], meaning that every input maps to exactly one output, and none repeat or are left out.~~		The RNG function has 65536 possible inputs and 65536 possible outputs. The function forms two loops, one of length 65534 and one of length 2, but one of the [[wikipedia:If statement\|if statements]] causes the cycle of 2 to lead back to the cycle of 65534.

	The function forms two loops, one of length 65534 and one of length 2, but one of the [[wikipedia:If statement\|if statements]] causes the cycle of 2 to lead back to the cycle of 65534.

	Oddly, the RNG value of 21674 at index 65113 loops back to index 0. This may be because this index's S1 value is equal to the previous RNG value for the first time, but that is no reason to prematurely end the loop.		Oddly, the RNG value of 21674 at index 65113 loops back to index 0. This may be because this index's S1 value is equal to the previous RNG value for the first time, but that is no reason to prematurely end the loop.

AgentMuffin at 20:55, 19 April 2025

2025-04-19T20:55:14Z

Show changes

Macrepeh at 01:03, 21 March 2020

2020-03-21T01:03:07Z

← Older revision		Revision as of 01:03, 21 March 2020
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	==References==		==References==
	<references />		<references />
			[[Category:Mechanics]]

Galoomba at 21:21, 20 March 2020

2020-03-20T21:21:52Z

← Older revision		Revision as of 21:21, 20 March 2020
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	==Cycling RNG==		==Cycling RNG==
	Because RNG ~~indeces~~ loop from 0 to 65113 and back to 0 again, by looping through every RNG index Mario can reach any reachable RNG value. By making [[dust]], Mario can advance RNG 4 times per frame, which takes 9 minutes to loop. If objects are calling RNG, this time will be much faster.		Because RNG indices loop from 0 to 65113 and back to 0 again, by looping through every RNG index Mario can reach any reachable RNG value. By making [[dust]], Mario can advance RNG 4 times per frame, which takes 9 minutes to loop. If objects are calling RNG, this time will be much faster.
	==Objects that call RNG==		==Objects that call RNG==
	The following objects always call RNG under the given circumstances.		The following objects always call RNG under the given circumstances.
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	* And many, many, many more.		* And many, many, many more.
	===[[Tick Tock Clock]] Random Setting Only===		===[[Tick Tock Clock]] Random Setting Only===
	The following objects call RNG under the given circumstances when the clock was entered at 6~~:00~~ (the random setting). Click on the link for more details.		The following objects call RNG under the given circumstances when the clock was entered at 6 (the random setting). Click on the link for more details.
	* [[Spinner#Random Setting\|Spinners]]		* [[Spinner#Random Setting\|Spinners]]
	* [[Cogs]] call RNG twice when they reach their target [[angular velocity]] (TAV)<ref>https://www.youtube.com/watch?v=S0q3_toE3b4</ref>. The cog approaches its TAV with an angular acceleration of ±50AU/frame². The first call determines the cog's next TAV. Because of the way the formula is structured, there is a possibility that the TAV is 0. If this occurs multiple times, the cog can stand still. The TAV is calculated by the following formula:		* [[Cogs]] call RNG twice when they reach their target [[angular velocity]] (TAV)<ref>https://www.youtube.com/watch?v=S0q3_toE3b4</ref>. The cog approaches its TAV with an angular acceleration of ±50AU/frame². The first call determines the cog's next TAV. Because of the way the formula is structured, there is a possibility that the TAV is 0. If this occurs multiple times, the cog can stand still. The TAV is calculated by the following formula:

Nim: /* The RNG function */

2019-05-21T19:18:09Z

The RNG function

← Older revision		Revision as of 19:18, 21 May 2019
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	function RNG:		function RNG:
	if RNGSeed = 22026:		if RNGSeed is 22026:
	set RNGSeed to 0		set RNGSeed to 0

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	Now we return the seed. 1010101001010101 in decimal is 43605, which is the expected result.		Now we return the seed. 1010101001010101 in decimal is 43605, which is the expected result.

	===Description===		===Description===
	[[File:RNG Graph.png\|500px\|right\|A graph showing notable RNG values and indices in SM64.]]		[[File:RNG Graph.png\|500px\|right\|A graph showing notable RNG values and indices in SM64.]]

Nim: updated

2019-04-14T22:12:07Z

updated

@@ Line 1: / Line 1: @@
-'''RNG''' or '''Random Number Generation''' is the game's method of generating a pseudorandom short. By doing this, the game can make things like dust movement seem random<ref>https://www.youtube.com/watch?v=MiuLeTE2MeQ</ref>.
+'''RNG''' or '''Random Number Generator''' is the game's [https://en.wikipedia.org/wiki/Pseudorandom_number_generator pseudorandom number generator]. It allows the game can make things like dust movement seem random<ref>https://www.youtube.com/watch?v=MiuLeTE2MeQ</ref>.
 ==Technical description==
-The RNG variable is a short, which is a number from 0 to 65535 inclusive. When an [[object]], [[snow]], or something else wants to call RNG, it takes the current RNG value and runs it through the '''RNG function''', below. It uses the result in its own calculations and also stores the result to the RNG variable. Thus, the RNG variable is equal to the last used RNG value. Every [[frame]], every object is iterated through in order of [[object slot]]s and may choose whether to call RNG once, multiple times, or not at all.
+The RNG consists of two parts: the evolution function (also known as the RNG function), and the seed. Whenever something (usually an [[object]]) wants to use the RNG, it calls the evolution function. The evolution function will read the seed, perform a series of mathematical operations on it, and return the new value of the seed. This means that the seed always reflects the last value that the RNG function returned. Because each object can load, unload, and use RNG multiple times per frame, the RNG function is often called an unpredictable number of times every frame. This makes the game's randomness often unpredictable even if you know the RNG function.
 ===The RNG function===
   <nowiki>
-unsigned short rng_function (unsigned short input) {
+set RNGSeed to 0
-     if (input == 0x560A) input = 0;
-     unsigned short S0 = (unsigned char)input << 8;
+function RNG:
-     S0 = S0 ^ input;
+     if RNGSeed = 22026:
-     input = ((S0 & 0xFF) << 8) | ((S0 & 0xFF00) >> 8);
+        set RNGSeed to 0
-     S0 = ((unsigned char)S0 << 1) ^ input;
-     short S1 = (S0 >> 1) ^ 0xFF80;
+    set value A to (the last byte of RNGSeed) shifted to the left by 1 byte
-     if ((S0 & 1) == 0) {
+     set value A to (value A) XOR (RNGSeed)
-         if (S1 == 0xAA55) input = 0;
-         else input = S1 ^ 0x1FF4;
+     set RNGSeed to value A
+    swap the bytes of RNGSeed
-     else input = S1 ^ 0x8180;
-    return (unsigned short)input;
+    set value A to (the last byte of value A) shifted to the left by 1 bit
+    set value A to (value A) XOR (RNGSeed)
 </nowiki>
 ===Description===
 [[File:RNG Graph.png|500px|right|A graph showing notable RNG values and indices in SM64.]]

MMMMMMMMMMMMM: /* Tick Tock Clock Random Setting Only */ make sense

2018-10-20T12:20:17Z

Tick Tock Clock Random Setting Only: make sense

← Older revision		Revision as of 12:20, 20 October 2018
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	* And many, many, many more.		* And many, many, many more.
	===[[Tick Tock Clock]] Random Setting Only===		===[[Tick Tock Clock]] Random Setting Only===
	The following objects call RNG under the given circumstances when the clock was entered at 6:00 (the random setting).		The following objects call RNG under the given circumstances when the clock was entered at 6:00 (the random setting). Click on the link for more details.
	* [[Spinner#Random Setting\|Spinners]] ~~call RNG twice~~		* [[Spinner#Random Setting\|Spinners]]
	* [[Cogs]] call RNG twice when they reach their target [[angular velocity]] (TAV)<ref>https://www.youtube.com/watch?v=S0q3_toE3b4</ref>. The cog approaches its TAV with an angular acceleration of ±50AU/frame². The first call determines the cog's next TAV. Because of the way the formula is structured, there is a possibility that the TAV is 0. If this occurs multiple times, the cog can stand still. The TAV is calculated by the following formula:		* [[Cogs]] call RNG twice when they reach their target [[angular velocity]] (TAV)<ref>https://www.youtube.com/watch?v=S0q3_toE3b4</ref>. The cog approaches its TAV with an angular acceleration of ±50AU/frame². The first call determines the cog's next TAV. Because of the way the formula is structured, there is a possibility that the TAV is 0. If this occurs multiple times, the cog can stand still. The TAV is calculated by the following formula:
	<nowiki>Target Angular Velocity = (RNG % 7) * 200</nowiki>		<nowiki>Target Angular Velocity = (RNG % 7) * 200</nowiki>

MMMMMMMMMMMMM: /* Tick Tock Clock Random Setting Only */

2018-10-20T12:19:55Z

Tick Tock Clock Random Setting Only

← Older revision		Revision as of 12:19, 20 October 2018
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	===[[Tick Tock Clock]] Random Setting Only===		===[[Tick Tock Clock]] Random Setting Only===
	The following objects call RNG under the given circumstances when the clock was entered at 6:00 (the random setting).		The following objects call RNG under the given circumstances when the clock was entered at 6:00 (the random setting).
	* [[Spinner#Random Setting\|Spinners]]		* [[Spinner#Random Setting\|Spinners]] call RNG twice
	* [[Cogs]] call RNG twice when they reach their target [[angular velocity]] (TAV)<ref>https://www.youtube.com/watch?v=S0q3_toE3b4</ref>. The cog approaches its TAV with an angular acceleration of ±50AU/frame². The first call determines the cog's next TAV. Because of the way the formula is structured, there is a possibility that the TAV is 0. If this occurs multiple times, the cog can stand still. The TAV is calculated by the following formula:		* [[Cogs]] call RNG twice when they reach their target [[angular velocity]] (TAV)<ref>https://www.youtube.com/watch?v=S0q3_toE3b4</ref>. The cog approaches its TAV with an angular acceleration of ±50AU/frame². The first call determines the cog's next TAV. Because of the way the formula is structured, there is a possibility that the TAV is 0. If this occurs multiple times, the cog can stand still. The TAV is calculated by the following formula:
	<nowiki>Target Angular Velocity = (RNG % 7) * 200</nowiki>		<nowiki>Target Angular Velocity = (RNG % 7) * 200</nowiki>

MMMMMMMMMMMMM: /* Tick Tock Clock Random Setting Only */ migrate spinner info

2018-10-20T12:19:32Z

Tick Tock Clock Random Setting Only: migrate spinner info

← Older revision		Revision as of 12:19, 20 October 2018
Line 39:		Line 39:
	===[[Tick Tock Clock]] Random Setting Only===		===[[Tick Tock Clock]] Random Setting Only===
	The following objects call RNG under the given circumstances when the clock was entered at 6:00 (the random setting).		The following objects call RNG under the given circumstances when the clock was entered at 6:00 (the random setting).
	* [[Spinner]]s call RNG twice when they stop spinning<ref>https://www.youtube.com/watch?v=MiuLeTE2MeQ</ref>. The first call determines direction. If the result is less than 32768, the spinner spins clockwise, and otherwise counterclockwise. The second call determines intended angular displacement. Spinners ~~calculate their intended angular displacement by the following formula, in which % denotes the [[wikipedia:modulo operation\|modulo function]]:~~		* [[Spinner#Random Setting\|Spinners]]
	~~<nowiki>Intended Angular Displacement = (RNG % 4) * 30 + 30</nowiki>~~

	~~The following is a table summarizing this information, with probabilities of the individual states in parentheses:~~
	~~{\| class="wikitable"~~
	\|-
	~~! [[Spinner]] intended CW ang disp ([[AU~~]]~~) !! RNG2 % 4 = 0 (24.982339%) !! RNG2 % 4 = 1 (24.999232%) !! RNG2 % 4 = 2 (25.008447%) !! RNG2 % 4 = 3 (25.009982%)~~
	\|-
	~~\| '''RNG1 ≥ 32768 (49.983107%)'''\|\| -30 (12.485794%) \|\| -60 (12.490401%) \|\| -90 (12.501152%) \|\| -120 (12.505759%)~~
	\|-
	~~\| '''RNG1 < 32768 (50.016893%)'''\|\| 30 (12.496545%) \|\| 60 (12.508831%) \|\| 90 (12.507295%) \|\| 120 (12.504223%)~~
	\|}
	* [[Cogs]] call RNG twice when they reach their target [[angular velocity]] (TAV)<ref>https://www.youtube.com/watch?v=S0q3_toE3b4</ref>. The cog approaches its TAV with an angular acceleration of ±50AU/frame². The first call determines the cog's next TAV. Because of the way the formula is structured, there is a possibility that the TAV is 0. If this occurs multiple times, the cog can stand still. The TAV is calculated by the following formula:		* [[Cogs]] call RNG twice when they reach their target [[angular velocity]] (TAV)<ref>https://www.youtube.com/watch?v=S0q3_toE3b4</ref>. The cog approaches its TAV with an angular acceleration of ±50AU/frame². The first call determines the cog's next TAV. Because of the way the formula is structured, there is a possibility that the TAV is 0. If this occurs multiple times, the cog can stand still. The TAV is calculated by the following formula:
	<nowiki>Target Angular Velocity = (RNG % 7) * 200</nowiki>		<nowiki>Target Angular Velocity = (RNG % 7) * 200</nowiki>