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Re: Strange issue when converting from hex to float
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Re: Strange issue when converting from hex to float


  • Subject: Re: Strange issue when converting from hex to float
  • From: Ian was here <email@hidden>
  • Date: Thu, 21 Jul 2005 11:52:22 -0700 (PDT)

I've tried several combos and they all yield a value
of zero.

float			fAlpha = alphaComp / 255.0f;

float                 fAlpha = (float)alphaComp /
255.0f;

float                 fAlpha = alphaComp / 255.0;


Doesn't seem to want to do the division??





--- Dan Treiman <email@hidden> wrote:

> Dividing an long by long integer returns a long,
> thats the way the C
> compiler does it.  And integer division truncates
> the result to an
> integer.
> Try casting one of your arguments as a float, that
> will force the
> compiler to generate floating point division
>
> i.e.
> float fAlpha = alphaComp / 255.0f;
>
> 	-DT.
>
> On Jul 21, 2005, at 11:54 AM, Ian was here wrote:
>
> > I have written a method that converts hex values
> to
> > floating point numbers. I am having a really
> strange
> > problem occur in the conversion process.
> >
> >
> >
> > // Convert each hex segment to decimal. This code
> > works fine!
> >
> > long			alphaComp = strtol( alphaValue, NULL, 16 );
> > long			redComp = strtol( redValue, NULL, 16 );
> > long			greenComp = strtol( greenValue, NULL, 16 );
> > long			blueComp = strtol( blueValue, NULL, 16 );
> >
> >
> >
> > The following code segment always returns zero!!??
>
> >
> > // Convert each decimal number to float.
> >
> > float			fAlpha = alphaComp / 255L;
> > float			fRed = alphaComp / 255L;
> > float			fGreen = alphaComp / 255L;
> > float			fBlue = alphaComp / 255L;
> >
> >
> > Any ideas would be greatly appreciated. Thank you.
> >
> >
> >
> >
> >
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  • Follow-Ups:
    • Re: Strange issue when converting from hex to float
      • From: John Stiles <email@hidden>
    • Re: Strange issue when converting from hex to float
      • From: Andy Lee <email@hidden>
References: 
 >Re: Strange issue when converting from hex to float (From: Dan Treiman <email@hidden>)

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