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Mail Archives: djgpp/2000/06/02/22:00:19

From: rob89 AT my-deja DOT com
Newsgroups: comp.os.msdos.djgpp
Subject: Re: Dos char set
Date: Fri, 02 Jun 2000 21:23:48 GMT
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Hello,
You said that each row is one byte. If there are 8 rows then would it
not mean that in total a character would be stored in 8 bytes? Does it
mean that the characters (in BIOS) are stored in 8 byte formats? I am
confused here as u said that they are stored in a bitmap...

Thanks,
Rob




In article <0fifjsgugpmpuvrkkp0rnthddapuliqrf0 AT 4ax DOT com>,
  Damian Yerrick <Bullcr_pd_yerrick AT hotmail DOT comRemoveBullcr_p> wrote:
> On Fri, 02 Jun 2000 07:30:34 GMT, rob89 AT my-deja DOT com wrote:
>
> >After this I could have some sort of for loop which goes through the
> >rows and columns and checks if there is a pixel there and if there
is,
> >display it on the screen using some function(say putpixel.). The code
> >has the following line which checks if there is a pixel in the
> >corresponding location:
> >
> >if((ch_table[string[index]][row] << column) & 0x80)
> >
> >I completely understand ch_table[string[index]][row] part, which
first
> >of all goes to the character to be displayed, but then I don't
> >understand why we have to shift left (<< column) and most importantly
> >why do we have to use masking (&0x80).
>
> The ROM font is stored as a monochrome bitmap to save space in ROM
> (each row is one byte), and you have to use shifting to convert a
> monochrome bitmap to 8-bit.
>
> --
> Damian Yerrick
> "I refuse to listen to those who refuse to listen to reason."
> See the whole sig: http://www.rose-hulman.edu/~yerricde/sig.html
>
> This is McAfee VirusScan. Add these two lines to your signature to
> prevent the spread of signature viruses.  http://www.mcafee.com/
>


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