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Groups > comp.lang.javascript > #39556

Re: Picture colors decreasing script.

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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?

-- 
PointedEars
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<https://github.com/PointedEars> | <http://PointedEars.de/wsvn/>
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Thread

Picture colors decreasing script. Kristjan Robam <kristjanrobam01@mail.ee> - 2021-02-28 22:33 -0800
  Re: Picture colors decreasing script. "Michael Haufe (TNO)" <tno@thenewobjective.com> - 2021-03-01 11:56 -0800
    Re: Picture colors decreasing script. Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2021-03-02 13:42 +0100
      Re: Picture colors decreasing script. "Michael Haufe (TNO)" <tno@thenewobjective.com> - 2021-03-03 07:02 -0800
        Re: Picture colors decreasing script. Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2021-03-03 19:47 +0100
          Re: Picture colors decreasing script. "Michael Haufe (TNO)" <tno@thenewobjective.com> - 2021-03-03 11:37 -0800
            Re: Picture colors decreasing script. Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2021-03-03 21:33 +0100
              Re: Picture colors decreasing script. "Michael Haufe (TNO)" <tno@thenewobjective.com> - 2021-03-03 12:38 -0800
                Re: Picture colors decreasing script. Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2021-03-03 21:53 +0100
                Re: Picture colors decreasing script. "Michael Haufe (TNO)" <tno@thenewobjective.com> - 2021-03-03 16:36 -0800
                Re: Picture colors decreasing script. Ben Bacarisse <ben.usenet@bsb.me.uk> - 2021-03-04 02:07 +0000
          Re: Picture colors decreasing script. John G Harris <niam@jghnorth.org.uk.invalid> - 2021-03-04 09:40 +0000

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