Difference between revisions of "Mutation Operators"
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__NOTOC__ | __NOTOC__ | ||
| − | '''Supported platforms:''' android | + | <!-- GIDEROSOBJ:Mutation Operators --> |
| + | '''Supported platforms:''' [[File:Platform android.png]][[File:Platform ios.png]][[File:Platform mac.png]][[File:Platform pc.png]]<br/> | ||
'''Available since:''' Gideros 2017.11<br/> | '''Available since:''' Gideros 2017.11<br/> | ||
| + | |||
=== Description === | === Description === | ||
| − | < | + | Operators to mutate a value. |
| − | + | ||
| + | *a<b> += </b>b = add 'b' to 'a' | ||
| + | *a<b> -= </b>b = subtract 'b from 'a' | ||
| + | *a<b> *= </b>b = multiply 'a' by 'b', result in 'a' | ||
| + | *a<b> /= </b>b = divide 'a' by 'b', result in 'a' | ||
| + | *a<b> %= </b>b = the result of 'a%b' is placed in 'a' | ||
| + | *a<b> ^= </b>b = the result of 'a^b' is placed in 'a' ('''^ is faster than a=math.pow(a,b)''') | ||
| + | *a<b> ^= </b>0.5 = the result is faster than a=math.sqrt(a) | ||
| + | |||
| + | === Examples === | ||
| + | '''Simple larger example''' | ||
| + | <syntaxhighlight lang="lua"> | ||
| + | score+=1 -- faster and less typing than score=score+1 | ||
| + | </syntaxhighlight> | ||
| + | |||
| + | '''"getDistance" function''' ('''see also the new <big>[[Math.distance]]</big> function''') | ||
| + | <syntaxhighlight lang="lua"> | ||
| + | --Non-optimized variant (5x slower): | ||
| + | function getDistance( x1, y1, x2, y2 ) | ||
| + | return math.sqrt(math.pow(x2 - x1, 2) + math.pow(y2 - y1, 2)) | ||
| + | end | ||
| − | + | --Optimized variant (5x faster): | |
| − | + | function getDistance2(x1, y1, x2, y2) | |
| − | + | return ((x2 - x1)^2 + (y2 - y1)^2)^0.5 | |
| − | + | end | |
| − | + | </syntaxhighlight> | |
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| − | + | {{GIDEROS IMPORTANT LINKS}} | |
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Latest revision as of 03:00, 1 December 2023
Supported platforms: 
Available since: Gideros 2017.11
Description
Operators to mutate a value.
- a += b = add 'b' to 'a'
- a -= b = subtract 'b from 'a'
- a *= b = multiply 'a' by 'b', result in 'a'
- a /= b = divide 'a' by 'b', result in 'a'
- a %= b = the result of 'a%b' is placed in 'a'
- a ^= b = the result of 'a^b' is placed in 'a' (^ is faster than a=math.pow(a,b))
- a ^= 0.5 = the result is faster than a=math.sqrt(a)
Examples
Simple larger example
score+=1 -- faster and less typing than score=score+1
"getDistance" function (see also the new Math.distance function)
--Non-optimized variant (5x slower):
function getDistance( x1, y1, x2, y2 )
return math.sqrt(math.pow(x2 - x1, 2) + math.pow(y2 - y1, 2))
end
--Optimized variant (5x faster):
function getDistance2(x1, y1, x2, y2)
return ((x2 - x1)^2 + (y2 - y1)^2)^0.5
end
