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William Leue
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Joined: 03/07/2020
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Posted: 04:07pm 13 Mar 2021

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The documentation on making fonts is a bit sparse IMHO.
We know this from the user manual:

DefineFont #n
' lots of 32-bit hex values
EndDefine Font

It looks as if the first hex value is used to define the number of words of memory used and the number of rows and columns in a character. But the usage does not seem to be be consistent in the extra fonts that are provided in the EmbeddedFonts folder.

By looking at the various fonts, I think the first 32-bit word is divided as follows:

Bits 0-7 : number of rows
Bits 15-8: number of columns
Bits 31-16: memory usage

For some of the example fonts, the value in bits 31-16 works out correctly to be the number of 16-bit words used in the font, but for others it does not.

Sorry if this has been covered before. Any clues?

Thanks!
-Bill

matherp
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Joined: 11/12/2012
Location: United Kingdom
Posts: 10310

Posted: 04:23pm 13 Mar 2021

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Bits 0-7 : number of rows
Bits 15-8: number of columns
Bits 16-23: font start ascii code - typically 0x20 = space
Bits 24-31: number of characters in font - typically 0x5F

William Leue
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Joined: 03/07/2020
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Posted: 07:07pm 13 Mar 2021

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Thanks, Peter!
-Bill

Geoffg

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Joined: 06/06/2011
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Posted: 09:26pm 13 Mar 2021

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This provides a full description: http://www.rinkydinkelectronics.com/h_utft_fonts_101.php

Geoff

Geoff Graham - http://geoffg.net

jirsoft

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Joined: 18/09/2020
Location: Czech Republic
Posts: 533

Posted: 10:52pm 13 Mar 2021

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Hi Bill,
for me was worst the rest, data payload (and I'm still hoping I have understand the format correctly, but somehow it works

).

So maybe take a look into SimplEd, on line 1365 begins SUB importing font from file, on 1249 is export...

Jiri
Napoleon Commander and SimplEd for CMM2 (GitHub), CMM2.fun

William Leue
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Posted: 02:53pm 14 Mar 2021

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Jiri,

Yes, I did look at SimplEd. I was having a hard time understanding the code. (My stupidity, not your fault.) So I decided to write a little code myself, since this is the best way for me to understand something fully.

I have a font reader that sort-of works. I can successfully read and display fonts that are defined on a 16x16 grid, e.g. arial_bold.bas and swiss_721_outline.bas.

But things go wrong on differently sized grids, with the resulting bitmaps getting distorted.

To make it work for arial_bold and similar fonts, I had to use a weird byte-oriented mapping from the data hex to the position of pixels in the font. I still don't understand why this works, or why it doesn't work for various sizes.

So, for instance, in a 16x16 font, each row of a font character is mapped from the data 32-bit numbers like this:

Column in Character Bit Position
------------------- ------------
1 7
2 6
3 5
4 4
5 3
6 2
7 1
8 0
9 15
10 14
11 13
12 12
13 11
14 10
15 9
16 8

In other words, I have to read the data byte-wise and scan each byte from higher-order to lower-order bits. This works fine for 16x16 fonts but fails for others.

Any clues? Thanks!
-Bill

matherp
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Posts: 10310

Posted: 03:56pm 14 Mar 2021

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Quote Any clues? Thanks!

Have a look at the MM.USER_BITMAP subroutine in this thread

William Leue
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Joined: 03/07/2020
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Posts: 405

Posted: 07:44pm 14 Mar 2021

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Thanks, Peter! That pretty much aligns with what I've already figured out.
-Bill

erbp
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Joined: 03/05/2016
Location: Australia
Posts: 195

Posted: 01:39am 15 Mar 2021

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Hi Bill,

You might like to check out the FontView Utility that I wrote about 12 months ago - see this thread. The font decoding is able to display various sized fonts correctly. I do agree that the decoding from the Hex values is quite "weird". Hopefully you can follow what the program is doing - I think I included plenty of comments, but its a while since I looked at code.

Cheers,
Phil.

TassyJim

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Joined: 07/08/2011
Location: Australia
Posts: 6283

Posted: 04:41am 15 Mar 2021

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Things to remember with fonts.
The character width x height should be a multiple of 8 so that a character ends on a full byte.
The number of bytes will not necessarily be a multiple of 4 so it is unlikely to end at a 32 bit word boundary. That makes working on one character at a time tricky.

After you have worked out the fond size etc, you can calculate the number of bytes for each character.

In FontTweak, I combine all the hex data after the first word into one long string.
Next I change the byte order for each word and separate the individual bytes.
Then I store the required number of bytes for each character in an array (still as strings)

To show a character, I fill an array from the character's string of bytes.

Procedure.l fillArray(txt.s)
Protected x.l, y.l, n.l ,b.l, num.l
For n = 0 To fontW*fontH-1 Step 8

thisByte = StringField(txt,n/8+1,",")
thisByte = "$"+Mid(thisByte,3,2)
num = Val(thisByte)
thisByte = RSet(Bin(num,#PB_Byte ),8,"0")
For b = 0 To 7
x = (n+b) % fontW
y = (n+b) / fontW
If Mid(thisByte,b+1,1)="1"
fontArray(x,y)=1
Else
fontArray(x,y)=0
EndIf
Next b
Next n

EndProcedure

Finally, show the character at what ever scale is required.

I haven't tried to convert the PureBasic code into MMBasic.

I have gone the other way - created a font from an image.

It might be of help:

CLS
dim integer pixX = 100
dim integer pixY = 100
dim integer charCount = 10
dim integer charStart = 48
dim integer charHeight = 50
dim integer charWidth = 32
dim integer ch,x,y,b
' print something to play with

TEXT pixX+1,pixY,"0123456789",lt,9

PRINT @(10,150), "" ' move the cursor to somewhere safe

open "test.fnt" for output as #2
' print the header
print #2, "DEFINEFONT #8"
txt$ = HEX$(charCount,2)+HEX$(charStart,2)+HEX$(charHeight,2)+HEX$(charWidth,2)
PRINT #2,txt$
txt$ = ""
for ch = 0 to 9
FOR y = 0 TO charHeight-1
FOR x = 0 TO charWidth -1
IF PIXEL(pixX+ch*charWidth +x,pixY+y)= 0 THEN pxl = 0 ELSE pxl = 1
outBuffer% = (outbuffer%<<1)+ pxl '<<7)
IF b MOD 8 = 0 AND b <> 0 THEN ' we have filled the first output group
chunk% = (chunk%>>8) + (outbuffer%<<24)
outBuffer% = 0
ENDIF
IF b MOD 32 = 0 AND b <> 0 THEN ' we have a 'word'
txt$ = txt$+ HEX$(chunk%,8)+" " ' fill the output line
IF LEN(txt$) > 70 THEN
PRINT #2,txt$
txt$ = ""
ENDIF
chunk% = 0
ENDIF
b = b + 1
NEXT x
NEXT y
next ch
txt$ = txt$+ HEX$(chunk%,8)+" "

PRINT #2,txt$
print #2,"END DEFINEFONT"
close #2

load font "test.fnt"
TEXT pixX+1,pixY+70,"0123456789",lt,8

END

DEFINEFONT #9
0A303220
00000000 00000000 00FEFF00 00FFFF01 80FFFF03 60FFFF01 F0FEFF0C F801001E
F801003F F801003F F801003F F801003F F801003F F801003F F801003F F801003F
F801003F F801003F F801003F F801003F F801003F 7800003E 18000038 08000020
00000000 00000020 18000038 7800003E F801003F F801003F F801003F F801003F
F801003F F801003F F801003F F801003F F801003F F801003F F801003F F801003F
F801003F F801003F F000001E 60FEFF0C 00FFFF01 80FFFF03 00FFFF01 00FEFF00
00000000 00000000 00000000 00000000 00000000 00000000 00000000 60000000
F0000000 F8010000 F8010000 F8010000 F8010000 F8010000 F8010000 F8010000
F8010000 F8010000 F8010000 F8010000 F8010000 F8010000 F8010000 78000000
18000000 08000000 00000000 00000000 18000000 78000000 F8010000 F8010000
F8010000 F8010000 F8010000 F8010000 F8010000 F8010000 F8010000 F8010000
F8010000 F8010000 F8010000 F8010000 F0000000 60000000 00000000 00000000
00000000 00000000 00000000 00000000 00000000 00000000 00FEFF00 00FFFF01
80FFFF03 60FFFF01 F0FEFF00 F8010000 F8010000 F8010000 F8010000 F8010000
F8010000 F8010000 F8010000 F8010000 F8010000 F8010000 F8010000 F8010000
F8010000 78000000 18FEFF01 88FFFF03 E0FFFF0F C0FFFF27 00FFFF39 0000003E
0000003F 0000003F 0000003F 0000003F 0000003F 0000003F 0000003F 0000003F
0000003F 0000003F 0000003F 0000003F 0000003F 0000003F 0000001E 00FEFF0C
00FFFF01 80FFFF03 00FFFF01 00FEFF00 00000000 00000000 00000000 00000000
00FEFF00 00FFFF01 80FFFF03 60FFFF01 F0FEFF00 F8010000 F8010000 F8010000
F8010000 F8010000 F8010000 F8010000 F8010000 F8010000 F8010000 F8010000
F8010000 F8010000 F8010000 78000000 18FEFF01 88FFFF03 E0FFFF0F C0FFFF07
18FFFF01 78000000 F8010000 F8010000 F8010000 F8010000 F8010000 F8010000
F8010000 F8010000 F8010000 F8010000 F8010000 F8010000 F8010000 F8010000
F0000000 60FEFF00 00FFFF01 80FFFF03 00FFFF01 00FEFF00 00000000 00000000
00000000 00000000 00000000 00000000 00000000 60000000 F000000C F801001E
F801003F F801003F F801003F F801003F F801003F F801003F F801003F F801003F
F801003F F801003F F801003F F801003F F801003F 7800003E 18FEFF39 88FFFF23
E0FFFF0F C0FFFF07 18FFFF01 78000000 F8010000 F8010000 F8010000 F8010000
F8010000 F8010000 F8010000 F8010000 F8010000 F8010000 F8010000 F8010000
F8010000 F8010000 F0000000 60000000 00000000 00000000 00000000 00000000
00000000 00000000 00000000 00000000 00FEFF00 00FFFF01 80FFFF03 00FFFF01
00FEFF0C 0000001E 0000003F 0000003F 0000003F 0000003F 0000003F 0000003F
0000003F 0000003F 0000003F 0000003F 0000003F 0000003F 0000003F 0000003E
00FEFF39 80FFFF23 E0FFFF0F C0FFFF07 18FFFF01 78000000 F8010000 F8010000
F8010000 F8010000 F8010000 F8010000 F8010000 F8010000 F8010000 F8010000
F8010000 F8010000 F8010000 F8010000 F0000000 60FEFF00 00FFFF01 80FFFF03
00FFFF01 00FEFF00 00000000 00000000 00000000 00000000 00FEFF00 00FFFF01
80FFFF03 00FFFF01 00FEFF0C 0000001E 0000003F 0000003F 0000003F 0000003F
0000003F 0000003F 0000003F 0000003F 0000003F 0000003F 0000003F 0000003F
0000003F 0000003E 00FEFF39 80FFFF23 E0FFFF0F C0FFFF27 18FFFF39 7800003E
F801003F F801003F F801003F F801003F F801003F F801003F F801003F F801003F
F801003F F801003F F801003F F801003F F801003F F801003F F000001E 60FEFF0C
00FFFF01 80FFFF03 00FFFF01 00FEFF00 00000000 00000000 00000000 00000000
00FEFF00 00FFFF01 80FFFF03 60FFFF01 F0FEFF00 F8010000 F8010000 F8010000
F8010000 F8010000 F8010000 F8010000 F8010000 F8010000 F8010000 F8010000
F8010000 F8010000 F8010000 78000000 18000000 08000000 00000000 00000000
18000000 78000000 F8010000 F8010000 F8010000 F8010000 F8010000 F8010000
F8010000 F8010000 F8010000 F8010000 F8010000 F8010000 F8010000 F8010000
F0000000 60000000 00000000 00000000 00000000 00000000 00000000 00000000
00000000 00000000 00FEFF00 00FFFF01 80FFFF03 60FFFF01 F0FEFF0C F801001E
F801003F F801003F F801003F F801003F F801003F F801003F F801003F F801003F
F801003F F801003F F801003F F801003F F801003F 7800003E 18FEFF39 88FFFF23
E0FFFF0F C0FFFF27 18FFFF39 7800003E F801003F F801003F F801003F F801003F
F801003F F801003F F801003F F801003F F801003F F801003F F801003F F801003F
F801003F F801003F F000001E 60FEFF0C 00FFFF01 80FFFF03 00FFFF01 00FEFF00
00000000 00000000 00000000 00000000 00FEFF00 00FFFF01 80FFFF03 60FFFF01
F0FEFF0C F801001E F801003F F801003F F801003F F801003F F801003F F801003F
F801003F F801003F F801003F F801003F F801003F F801003F F801003F 7800003E
18FEFF39 88FFFF23 E0FFFF0F C0FFFF07 18FFFF01 78000000 F8010000 F8010000
F8010000 F8010000 F8010000 F8010000 F8010000 F8010000 F8010000 F8010000
F8010000 F8010000 F8010000 F8010000 F0000000 60FEFF00 00FFFF01 80FFFF03
00FFFF01 00FEFF00 00000000 00000000 00000000
END DEFINEFONT

Jim

VK7JH
MMedit

William Leue
Guru

Joined: 03/07/2020
Location: United States
Posts: 405

Posted: 11:43am 16 Mar 2021

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Phil said:

Quote Hi Bill,

You might like to check out the FontView Utility that I wrote about 12 months ago - see this thread. The font decoding is able to display various sized fonts correctly. I do agree that the decoding from the Hex values is quite "weird". Hopefully you can follow what the program is doing - I think I included plenty of comments, but its a while since I looked at code.

Cheers,
Phil.

Oh, thanks! I had totally forgotten about this.

-Bill

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