[comp.sys.mac] Can ROM fonts be modified?

sandrock@uxc.cso.uiuc.edu (11/19/87)

     Can someone please tell me if there is a way to modify the Chicago 12
   font on a Mac Plus?  I understand that although this font resides in ROM,
   that there is a way this can be done.

     Thanks,

		Mark Sandrock, (sandrock@uxc.cso.uiuc.edu)

jbm652@uxa.cso.uiuc.edu.UUCP (11/20/87)

I know there's an INIT which is available for that purpose and can be
found on a few Japanese BBS's.  I don't have a copy right now, but I might
be able to obtain it while I'm in Japan this winter...

---
John Melby, student, University of Illinois
Disclaimer:  When I return from Japan, my new uxf signon will have different
 random digits on the end.
---

jonesg@pc.ecn.purdue.edu.UUCP (11/20/87)

I also want to know where to get information on creating/modifying
fonts.  There are a few things of symbolic type that we can not
get anywhere else but in Zapf Dingbats.  I would like to make
similar doo-hickeys and put them in a special package.  Just point
me to the appropriate manuals.

Glynda Jones Davis
(There she goes begging again.....tsk tsk tsk!)

lippin@spam (The Apathist) (11/22/87)

Recently sandrock@uxc.cso.uiuc.edu said:
>
>     Can someone please tell me if there is a way to modify the Chicago 12
>   font on a Mac Plus?  I understand that although this font resides in ROM,
>   that there is a way this can be done.

All you need to do is open up a resource file with another Chicago 12
font (with the same name and number) and an appropriate FOND resource.
In the resource manager section of IM IV, there's a descripton of how
to make ROM-override resources, but this is't necessary for fonts.

					--Tom Lippincott
					..ucbvax!bosco!lippin

	"It's a multi-purpose shape: a box." -- David Byrne

ws0n+@andrew.cmu.edu (Walter Ray Smith) (11/22/87)

To replace a font in ROM, you must add entries to the 'ROv#' resources in the 
System file.  Each ROM version has an associated resource, but I believe you 
can add the new entry to all the 'ROv#'s with no bad effects.  ResEdit has a 
template for 'ROv#'s, so you just open each one, select the bottom line of 
*****, use the New command, and enter the resource type and ID you are 
replacing.  For example, to replace Chicago-12, you would use type 'FONT' and 
ID 12.  This will cause the system to use the FONT 12 resource from the System 
file rather than the one in ROM.

If this isn't clear enough, send me mail.

- Walt

garth@swatsun (Garth Snyder) (11/24/87)

>  Recently sandrock@uxc.cso.uiuc.edu said:
>  
>   Can someone please tell me if there is a way to modify the Chicago
>   12 font on a Mac Plus?  I understand that although this font resides
>   in ROM, that there is a way this can be done.
>  
>  And lippin@spam.UUCP (Tom Lippincott, ..ucbvax!bosco!lippin) replied:
>  
>   All you need to do is open up a resource file with another Chicago
>   12 font (with the same name and number) and an appropriate FOND
>   resource.  In the resource manager section of IM IV, there's a
>   descripton of how to make ROM-override resources, but this is't
>   necessary for fonts.

This is true as far as it goes, but if I remember correctly you can't use
this method if you want to make an across-the-board change rather than
just a substitution in one particular application.  Note also that you
don't have to open a separate resource file, you can just paste a private
copy of the font into the application's resource fork and it will be used
automatically.

--------------------
Garth Snyder            UUCP: {seismo!bpa,rutgers!liberty}!swatsun!garth
Swarthmore College      ARPA: garth@boulder.colorado.edu
Swarthmore, PA 19081    ALSO: {hao,nbires}!boulder!garth
--------------------

earleh@dartvax.UUCP (Earle R. Horton) (12/07/87)

1)  Remove the ROMs from your Mac.  Find someone with a PROM programmer
    which can dump their contents to a disk file on your Mac through
    the serial port.  Temporarilly replace the ROMs if you have only
    one Mac to work with.  Since the PROM programmer will probably
    send the file to your Mac in hex format, determine at this point
    the specifications for the hex format so you can convert it to 
    a raw byte file.

2)  Ask your Apple dealer to recommend a compatible EPROM type to 
    replace the ROMs in your Mac.  If he doesn't know, go back to 
    the fellow with the PROM programmer, who can probably help you
    figure it out.

3)  Extract the FONT resource to a resource file.  You may have to
    write a program to do this.  Make a copy of this file to work with.

4)  Determine the size of the FONT resource which you have extracted
    from the ROM.  The new ROM FONT resource which you will create 
    must be no larger than this.

5)  Modify the FONT in your work file to your specifications.
    Take care that you do not increase its size.

6)  Compare the contents of the file created in (1) with those of your
    original FONT file from (2), and determine the starting address of
    the FONT in ROM.

7)  Write a program to replace the FONT in the raw file with the 
    modified FONT which you have created.  After this step, you are
    ready to program your new set of ROMs.  If you have an SE, you
    might at this point consider how YOUR picture would look in there.
    Take care when you do this to REPLACE the bytes in your original
    raw file, and never INSERT bytes when replacing ROM resources.

8)  I'm just kidding, but wouldn't it be fun?
-- 
*********************************************************************
*Earle R. Horton, H.B. 8000, Dartmouth College, Hanover, NH 03755   *
*********************************************************************

ws0n+@andrew.cmu.edu (Walter Ray Smith) (12/09/87)

You can save a lot of time by just reading the ROM into a Mac file yourself.  
I mean, that's why it's connected to the processor, to be read, right?  Also, 
anyone willing to go to this much trouble will be willing to find the ROM 
resource map and re-do it to point to the new font, no matter how big it is.  
:-)

But seriously, for the imminent day when the 128K ROM upgrade is discontinued, 
does anyone already know the best (i.e., most convenient) PROM to use in a Mac 
512?  Not that I'm advocating copying Apple ROMs, because of course that would 
be illegal...

- Walt
--
       Walter Smith, CS graduate student, Carnegie-Mellon University
      uucp: ...!seismo!cmucspt!wrs ?         ARPA: wrs@f.gp.cs.cmu.edu
              usps: 5706 Darlington Rd.; Pittsburgh, PA  15217