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Huge Character Demo
Posted: Wed Jun 01, 2022 8:19 pm
by mobluse
Huge Character Demo prints all the characters in the ROM hugely: PETSCII and ISO8859-15 including ASCII. The faster version uses some new X16 BASIC v2 keywords: BIN$ and LOCATE, but the slower R38 version uses BASIC code or SYS PLOT to do the same. Both programs use the SYS FETCH Kernal function to read character data from ROM bank 6. It's the slower R38 version that runs using the Try it now button. The zip-file contains a version for R38+ and faster versions for R39+ and the open source code as text. This is FOSS with GPLv3 license. One could e.g. develop this into a program to print banners.
This is also on GitHub: https://github.com/mobluse/chargen-maker
I'm open to suggestions on how to improve the code and make it faster.
I added a specific version for R39 since the R41 version didn't work there. I also included the source file chars.bas for R39+.
It can be run from the command line if you first unzip chars-x16.zip:
x16emu -bas chars.bas -run
Re: Huge Character Demo
Posted: Fri Apr 07, 2023 12:56 am
by mobluse
Try It Now!!
I didn't yet want to make a new release, but included a manifest so that
Try it now works. I don't have the rights update the original post. You can read more about
Huge Character Demo at:
viewtopic.php?t=3036
(BTW this thread should be in the Archive, since this was posted before the new forum.)
#R38 #R39 #R41 #R42 #R43
Re: Huge Character Demo
Posted: Thu May 18, 2023 11:46 pm
by ahenry3068
I remember doing a similiar project on PC compatibles... Its quite useful for title screens to be able to print large
fonts... I don't have quite the agile brain I had when I was in my 20's ....lol. I find your
loop code a little obfuscated
..
I broke this routine out in a Pascal Unit. (like a library in C or a DLL in windows). To
Print a Single ROM character starting at a specific Screen X, Y.
I know your mapping the bitmap font... I'm just not quite following the code to break it
out for a single character subroutine. ???
Re: Huge Character Demo
Posted: Fri May 19, 2023 12:25 am
by ahenry3068
You shouldn't worry about speed so much. Breaking if out to print
a single character giving the asc code would be much
more useful.
Re: Huge Character Demo
Posted: Mon May 22, 2023 6:03 pm
by mobluse
I don't have time right now to make a version of this program that prints a single, freely chosen, character, but I could modify it so that it starts printing a chosen character "X":
Code: Select all
1020 FOR P=$C000+8*(ASC("X")-ASC("A")+1) TO T
Re: Huge Character Demo
Posted: Mon May 22, 2023 11:46 pm
by ahenry3068
Thanks for the reply. Actually I think that one line of code isolated has helped.
When I wrote the function it took 2 parameters. The string to print and the ASCII code to use as the block character.
Then it just read the ROM font and used the code sent as the "PIXEL". Another parameter just used the
character being drawn as the block character
I ended up using this mostly for program SPLASH/TITLE screens when they started up.
Re: Huge Character Demo
Posted: Tue May 23, 2023 1:45 am
by Daedalus
OMG! This gives me flashbacks to when I was programmed my TRS-80 to display stuff in it's (cough) "graphics mode" one giant monochrome pixel at a time.
Re: Huge Character Demo
Posted: Tue Aug 08, 2023 10:37 pm
by ahenry3068
I'm trying to recreate a more modular version of this. Single Letter or word at a time.
I have to confess I'm really not following the code very well.
I know that the character font is in the ROM in Bank 6. I'm missing the
docs that tell how the font is laid out in memory though. And I'm not quite getting it
from this code
Re: Huge Character Demo
Posted: Tue Aug 08, 2023 10:59 pm
by ahenry3068
Yeah I got a single letter to work.
easy peasy from here.
I did get one thing from the code here. I was not correctly calculating the offset.
Your previous answer and your code at least got me on the correct track... TY.
I would still like to find more docs on how the character font is laid out in memory. I'm
pretty sure at least the default font is laid out as an 8x8 monochrome bitmap otherwise
my code wouldn't be working...