| From: | Olaf Barthel |
| Date: | 04 Aug 99 at 20:18:03 |
| Subject: | RE: Into chip |
From: "Olaf Barthel" <olsen-amigac@sourcery.han.de>
On Aug 4 Jesper (Jesper Svennevid) wrote:
> From: "Jesper Svennevid" <jesper@fxrealm.com>
>
> > From: Volker Barthelmann <volker@vb.franken.de>
> >
> > On Tue, 3 Aug 1999, Jens Granseuer wrote:
> > > Lee Atkins <lee@loonyjuicesoftware.freeserve.co.uk> wrote:
> > >
> > > > How do I specify that an array has to go into chip ram using VBCC.
> > > > I want to stick some bitplanes in there and I dont want to
> > have to allocate
> > > > some chip and copy it in.
> >
> > __chip mytype myarray[]={...};
> >
> > > Not at all. You'll have to allocate some chip mem manually and copy
> > > the bitplanes into it yourself.
> >
> > Recent versions of vbcc support the __chip keyword.
>
> But that wouldn't be quite proper imho :) ... 1) Gfx-board support is
> very non-existant 2) It does not guarantee 8-byte alignment, which is
> a requirement on AGA-equipped systems. Using AllocBitMap() or
> AllocRaster() guarantees that alignment.
64 bit alignment is mandatory only for the display controller, it needs
that alignment in order to be able to do burst accesses. That alignment
requirement does not hold true for the blitter, which is still the same old
16 bitted beast it used to be in the original Amiga chip set. Embedding small,
blittable chunks of bitmap data in a program is common practice. Now, embedding
large displayable chunks of image data in a program, that's what I would call
questionable programming practice.