Re: gEDA-user: pcb crooked traces

[karl@xxxxxxxxxxx (Karl Hammar)]

John Doty:
> Karl Hammar wrote:
> > So, in what way are floats worse than ints (I'm talking about 
> > representaion, not about performance) and why could we not "reasonably 
> > use floating-point"?
> The problem is that in engineering documentation, dimensions are
> generally given as decimal fractions of inches or meters.

Yes.

> Cumulative roundoff error can be avoided if the numeric encoding
> can exactly represent such numbers.

Yes.

> Scaled integers or scaled floating point may be used,

Yes.

> but scaled integers are a bit easier to use and understand,

Yes (but we are talking about internal values, the user don't have to 
"see" them, only the developers, think of todays "1mm").

> and are usually more efficient.

You choose the most efficient one, to do that you test.
But I was not talking about performance.

> Unscaled binary floating point is troublesome because it cannot
> exactly represent most decimal fractions, so it is prone to
> cumulative error.

Yes.

Regards,
/Karl Hammar

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