[fpc-pascal] FPImage and GetDataLineStart

Michael Van Canneyt michael at freepascal.org
Thu Apr 21 21:08:41 CEST 2011



On Thu, 21 Apr 2011, Marco van de Voort wrote:

> In our previous episode, Mattias Gaertner said:
>> >> GetScanLine/SetScanLine,
>> >> and all other FPIMage operations will work equally well.
>> >
>> > This will not accelerate reading/writing at all. When writing (or any other
>> > form of streaming), there will still be a procedure call per pixel and
>> > conversion to/from 64-bit.?
>> Yes, it does, because of cache effects.
>
>
> If you declare your class as e.g. TBW32image (RGBA), a pixel assignment is
> an inline handful of instructions.
>
> I think fcl-image with its no-compromise format support was great initial
> effort.  But it is time to at least allow some internal shortcuts for
> performance's sake. And generics allow a way to put this into a class
> hierarchy without too much code duplication.

You can propose whatever you want _but_ generics.

Michael.



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