From: "Michael Stewart" <mike AT reggin DOT freeserve DOT co DOT uk>
Newsgroups: comp.os.msdos.djgpp
Subject: Re: Polygon scan problem
Date: Mon, 18 Jan 1999 20:34:39 -0000
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To: djgpp AT delorie DOT com
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Nate Eldredge wrote in message <36A38DCC DOT A93B9488 AT cartsys DOT com>...
>Michael Stewart wrote:
>>
>> I have been having an annoying problem whilst writing a scan convertor.
>> Hopefully someone will be able to see what I am doing wrong.
>>
>> The problem I have been having concerns the accuracy of fixed point
values.
>> The routine works as it should while using doubles, however when
converting
>> to fixed point values I loose an enormous amount of accuracy, to much to
be
>> accounted for by the accuracy of a 16.16 fixed point value.
>>
>> I have tried using Allegros fixed point routines instead of my own and I
get
>> the exactly the same problem. Can anyone see what I am doing wrong ?
>
>Conversions between integer and `fixed' need to call the appropriate
>routine (`itofix' or `fixtoi').
>--
>
>Nate Eldredge
>nate AT cartsys DOT com

Sorry, I forgot to mention. I have been using the fixed point class from
Allegro. All the operators are overloaded so I shouldn't need to call itofix
or fixtoi.