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From: Thomas 'PointedEars' Lahn <PointedEars@web.de>
Newsgroups: comp.lang.javascript
Subject: Re: Picture colors decreasing script.
Date: Wed, 03 Mar 2021 19:47:03 +0100
Organization: PointedEars Software (PES)
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Message-ID: <5689266.lOV4Wx5bFT@PointedEars.de>
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Michael Haufe (TNO) wrote:

> On Tuesday, March 2, 2021 at 6:42:26 AM UTC-6, Thomas 'PointedEars' Lahn
> wrote:
>> Michael Haufe (TNO) wrote:
>> > Also for readability the following:
>> > 
>> > ```
>> > var a1=imgData.data[i];
>> > var a2=imgData.data[i+1];
>> > var a3=imgData.data[i+2];
>> > var a4=imgData.data[i+3];
>> > ```
>> > 
>> > I think can be replaced with:
>> > 
>> > ```
>> > let {data} = imgData
>> > let [r,g,b,a] = [data[i], data[i+1], data[i+2], data[i+3]]
>> > ```
>> let [r,g,b,a] = data.slice(i, i + 4);
>> 
>> :)
> 
> Yes, that's shorter but when dealing with ImageData in a loop you
> definitely don't want to do this due to the significant performance
> penalty (at least an order of magnitude).

What is the functional difference between your code and mine?

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