Re: fixed point vs floating point

["Dmitry A. Kazakov" <mailbox@dmitry-kazakov.de>]

On Fri, 30 Sep 2011 16:25:22 +0000 (UTC), tmoran@acm.org wrote:

> Intensities (eg color, sound) are always fractions, but they are usually
> represented as if they were integers ranging from 0 ..  15, or 0 ..  255,
> or 0 ..  65535.  Code like
>   Is_Bright := (Color > 128);
> is much more tedious and error-prone to change then
>   Is_Bright := (Color > 0.5);

Right, but arithmetic of color-models intensities is not linear, so
although a fixed point type would be far more convenient for color stimuli,
it still would require redefinition of the operations.

An addition to your list: screen units (horizontal, vertical coordinates).
Traditionally rendering frameworks are using floating point for them, but I
think that fixed point could be more suitable with regard of anti-aliasing
issues etc.

to the OP: Integer type is a special case of decimal fixed point. So I
don't understand your desire to single out signed integer types them.
However, for the modular ones, it would indeed make sense.

-- 
Regards,
Dmitry A. Kazakov
http://www.dmitry-kazakov.de