[Gridflow-dev] ping (fwd)

Mathieu Bouchard matju at sympatico.ca
Thu Sep 9 07:20:46 EDT 2004

replying to: Tom Schouten <doelie at zzz.kotnet.org>
> > > bitgrid/8/320/240/3
> > > this describes a 8 bit, planar row encoded image: w=320 h=240 planes=3
> > I'm not sure what you mean. Is it like char[3][240][320], or like another
> > C array shape?

> > GridFlow 0.7 has two 32-bit types (i,f) and two 64-bit types (l,d). How
> > would you differentiate between int and float in general? and signed vs
> > unsigned?
> i don't. i don't need generic grids yet, only to implement permutations
> and have at least some raw bit representation.

Yes, but GridFlow needs to differentiate between them.

> my matrices are floating point, images are fixed point.

So would your converters consider that float==matrix and int==image, in
both GF->PDP and PDP->GF ?

> > Besides, GridFlow does not use planes at all, ever, unlike, say, Jitter.
> what do you mean? the planes are just your outer dimension wrt to memory
> layout, no? if that happens to be colour, you have planar data.

Well, that's a strange definition of planes.

Jitter has a concept of planes directly in its data model that corresponds
exactly to the one of channels and that causes images to be only
two-dimensional because the channels are considered not a real
dimension. Besides, I've only ever heard of "planes" to mean something at
the color channel level (see also: X11, EGA, etc).

> gcc 3, but use 3.3.1 or higher.

OK, I'll see if I can afford to make that move within the next years. I'm
still using GCC 3.2.2 at home, and until I can upgrade all of my platforms
to GCC >= 3.3.1, I'm not going to depend on that for performance.

> gcc 3 is really nice, but a lot of the optimization code seems buggy.

What kind of bugs are you thinking about?

Mathieu Bouchard                       http://artengine.ca/matju

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