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An ACS library for ZDoom-based ports

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rounding [2017/03/15 16:39] – created korshunrounding [2019/08/26 21:02] (current) – korshun
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-===== Rounding =====+====== Rounding====== 
 + 
 +===== Introduction ===== 
 + 
 +ACSUtils provides a full set of functions to round fixed-point numbers to integers. 
 + 
 +<note warning>Current GZDoom provides built-in functions [[zdoom>Floor_(ACS_function)|floor]], [[zdoom>ceil]] and [[zdoom>round]], but these functions aren't available in Zandronum 3.0 and **silently return 0** there, because all unimplemented built-in ACS functions return 0. 
 + 
 +Before using ACSUtils, rename either the built-in functions (by editing ''zspecial.acs'') or the ACSUtils functions (by editing ''acsutils.acs'') to something else. Otherwise, ACSUtils won't compile. 
 +</note> 
 + 
 +===== Rounding modes =====
  
 There are four rounding modes: There are four rounding modes:
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   * ''round'' -- rounds the number to the closest integer   * ''round'' -- rounds the number to the closest integer
  
-Rounding table:+A table that demonstrates the differences between rounding modes:
  
 ^  x   ^ round(x) ^ floor(x) ^ ceil(x) ^ trunc(x) ^ ^  x   ^ round(x) ^ floor(x) ^ ceil(x) ^ trunc(x) ^
-^   2.3|         2|         2|        3|         2| +^   1.3|         1|         1|        2|         1| 
-^   3.8|         4|         3|        4|         3| +^   1.5|    1 or 2|         1|        2|         1| 
-^   5.5|         6|         5|        6|         5| +^   1.8|         2|         1|        2|         1| 
-^  -2.3|        -2|        -3|       -2|        -2| +^  -1.3|        -1|        -2|       -1|        -1| 
-^  -3.8|        -4|        -4|       -3|        -3| +^  -1.5|  -2 or -1|        -2|       -1|        -1| 
-^  -5.5|        -5|        -6|       -5|        -5|+^  -1.8|        -2|        -2|       -1|        -1| 
 + 
 +===== Functions ===== 
 + 
 +Every rounding mode is available as two functions: 
 +  * Functions without the ''i'' prefix return a fixed, e.g. ''floor(2.3) == 2.0''. 
 +  * Functions with the ''i'' prefix return an int, e.g. ''ifloor(2.3) == 2''. 
 + 
 +^ Mode  ^ fixed result ^ int result ^ 
 +^ floor | ''fixed floor(fixed x)'' | ''int ifloor(fixed x)'' | 
 +^ ceil  | ''fixed ceil(fixed x)''  | ''int iceil(fixed x)''  | 
 +^ round | ''fixed round(fixed x)'' | ''int iround(fixed x)'' | 
 +^ trunc | ''fixed trunc(fixed x)'' | ''int itrunc(fixed x)'' | 
  
-Every rounding mode is available as two functions. The ones with the "i" in the name return an integer, while the ones without the "i" return a fixed. 
  
rounding.1489588751.txt.gz · Last modified: 2017/03/15 16:39 by korshun

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