[Vm-dev] Byte ordering in Form (urgent)

Ronie Salgado roniesalg at gmail.com
Thu Oct 11 19:32:53 UTC 2018

Hi Eliot,

I usually use depth: -32 for my stuff, because it corresponds with the
common BGR_sRGB_A8_UNORM, which tends to be used commonly by the graphics

Best regards,

El jue., 11 oct. 2018 a las 15:34, tim Rowledge (<tim at rowledge.org>)

> > On 2018-10-11, at 11:27 AM, Bert Freudenberg <bert at freudenbergs.de>
> wrote:
> >
> > No, positive depth means big endian on all platforms.
> >
> > Until Andreas added little endian support to bitblt, everything was done
> in big endian, and only reversed on copying to the OS window. That byte
> reversal was expensive, so that's why the little endian support was added,
> to be able to keep forms in native order on little endian platforms. Little
> endian is indicated by negative depth, also in the platform support code
> (e.g. supportsDepth).
> IIRC from far too long ago I concluded that the littleendian stuff Andreas
> added was very specifically Windows weird idea of littleendian, which
> involved some strange stuff for less than 32bpp forms. It certainly didn't
> work on RISC OS.
> tim
> --
> tim Rowledge; tim at rowledge.org; http://www.rowledge.org/tim
> Useful random insult:- Calls people to ask them their phone number.
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