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From: dac@prolix.pub.uu.oz.au (Andrew Clayton)
Newsgroups: comp.sys.amiga.programmer
Subject: Re: Here's an EASY one [Char Set Interp] (kinda long)
Message-ID: <18fdcf2e.ARN19ac@prolix.pub.uu.oz.au>
Date: 15 Apr 91 10:33:50 GMT
References: <18f0bf14.ARN1771@prolix.pub.uu.oz.au> <1080@cbmger.UUCP> <18f73ee5.ARN18a5@prolix.pub.uu.oz.au>
 <18fa0585.ARN1913@prolix.pub.uu.oz.au> <70793@eerie.acsu.Buffalo.EDU>
Reply-To: dac@prolix.pub.uu.oz.au
Followup-To: comp.sys.amiga.programmer
Organization: More like Mis~, really.
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In article <70793@eerie.acsu.Buffalo.EDU>, Jeffrey C Murphy writes:

> In article <18fa0585.ARN1913@prolix.pub.uu.oz.au>, dac@prolix.pub.uu.oz.au (Andrew Clayton) writes...

> >Harking back to my original question; there are bitmaps for each character in
> >a font, available [somehow] via pointers to structures in the font.  I need to
> 
> >format, I pass a string to my program, and it uses the character passed as a
> >jump into the font structure, and then I examine what bitmap is available, and
> 
>  Ok. If I understand you correctly you are looking for a pointer to where the
> font bitmaps are stored. Ok? When you call OpenFont() or OpenDiskFont() they
> will return a pointer to a TextFont structure containing info on the font
> (or a null if it could not locate the font). The TextFont structure looks like
> this:

Yep.  I pored over the (1.1) Rom Kernal Reference Manual, and found out all
about tf_Chardata and tf_Charloc. Getting hold of these with Arexx is proving
to be a headache.

What I _really_ want to do, is go to the Rastport to find the window I'm
using, and then use that's copy of the textfont pointer to leap into the
textfont structure, then I can do fancy fonts and be able to enlarge those
with no extra effort, if you see what I mean.

[Textfont structure deleted]

And thankyou for including that. I can get Arexx to tell me the address of
FONTS [say c2x(Showlist('a',FONTS,A))], and using that address, I can use
IMPORT to look at memory.

The 'clue' that I needed was the existence of the 'IMPORT' command in Arexx; I
pored over the manual, page by page, looking for something to READ MEMORY. It
took me a while to find it. :-(

[interesting bits about Charloc and tf_Modulo deleted]

>  So you have to set up a textAttr structure and call Open(Disk)Font() with
> a pointer to this structure. Then, in return, you get a pointer to the 
> TextFont structure which you use to access the font's bitmap. 

Yes, that makes sense. 

I think I'll throw away the Arexx idea, and us a language that understands
structures [in other words, I'll cheat and use Modula 2, which has all the
include files defined already - I would have liked to do it in Arexx though.
Sigh.]

>  Hope this answered your original question.

If it had come one day earlier, it would have saved me a lot more time.
Thankyou very much for your explanation, it was exactly what I wanted. 

> jm  

Dac
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