Simple Font-Library

[Postmann]

Hey :)

I wrote this for one of my projects. It loads and displays fonts loaded from bitmap-files. I added 5 fonts to the demo (The 3 default fonts from FreeBasic + 2 fonts I use in my project). No libraries needed, FB only.

There are 3 commands/functions in it:

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DrawString (STRING, X, Y, FONT)     'draws a string with the specified font
ColorRGB (RED, GREEN, BLUE, FONT)   'works like "Color RGB()"
FontWidth (STRING, FONT)            'returns the length of a string in pixel

Download

[datwill310]

Looks interesting! May be very useful for my game (I quite like the fonts for screen modes like 20, but as they say, variety is the spice of life)!

[xlucas]

That's very nice, mate. I was also thinking of a way to make fonts in FreeBasic that could change colour, like the default one, but that would also use different intensities and I came up with an idea I haven't tried yet.

[Bad_Idea]

Hey, I am "Postmann". I just forgot my password.

I've rewritten the library. It now supports nearly every latin/germanic based language and the €uro-sign. The fonts can be scaled, colored and rendered bold, italic and underlined. It is working on Windows, Linux and DOS.

Download from freebasic-portal.de


The Download includes the fonts of the "GNU-FreeFonts" project. FreeSans, FreeSerif and FreeMono are saved in an own format.
When you want to include your own fonts, be sure to take a look at "TFont.Load()" in the file "font.bi". The first byte in the header contains the pixel-height of all characters. The next 101 bytes contain the width of every character. The rest is basically a compressed BMP-file, where I have rendered 101 characters (All printable Ascii-chars + the german letters "ÄÖÜäöüß" + €) into. Every bit is one pixel.

[thebigh]

Hope it's OK to bump this, but I've got an issue that I can't understand. I'm testing this with the following code, compiling in Linux Mint 18.1 MATE 64 bit:

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const depth=8

#include once"gfx.bi"
#include once"font.bi"

screenres 640,480,depth

Dim As TFont Font
Font.Load("mono.fnt")

Font.DrawString(,"Hello, World!", 10, 10 )

sleep
end

This works fine with mono.fnt and serif.fnt. but when I try it with sans.fnt I get the following error:

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Error in `./hello': free(): invalid pointer: 0x0000000000d9a6a0

The demo.bas program that comes with the library works without issue. I can't see what my simpler code is doing differently. What am I doing wrong?

[sancho3]

I'm on Ubuntu and your code works fine.
Where is the error message getting "Free()" from? That function is not in any of the files.
Also make sure that the program is finding 'mono.fnt'. There is no error message or return value to indicate if load worked (BadIdea I recommend some kind of return value for the load procedure).
I had to use the full path to the file.

[thebigh]

Yeah, mono and serif work fine, but sans gives me that weird error. The text gets displayed on the screen, but then it displays the error message in the terminal and crashes so that I have to Ctrl-C out of it.

[sancho3]

Oh sorry, I didn't see that part of your post.
I just tried it with sans (on Ubuntu and it worked fine as does serif.
Perhaps sans.fnt is corrupt. Mine is 927 bytes.

[Lachie Dazdarian]

This is really cool.

[badidea]

Hope it's OK to bump this, but I've got an issue that I can't understand. I'm testing this with the following code, compiling in Linux Mint 18.1 MATE 64 bit:
(code)
This works fine with mono.fnt and serif.fnt. but when I try it with sans.fnt I get the following error:

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Error in `./hello': free(): invalid pointer: 0x0000000000d9a6a0

The demo.bas program that comes with the library works without issue. I can't see what my simpler code is doing differently. What am I doing wrong?

Similar behaviour here (crash).
FBC32:
test: malloc.c:3722: _int_malloc: Assertion `(unsigned long) (size) >= (unsigned long) (nb)' failed.
FBC64:
*** Error in `./test': corrupted size vs. prev_size: 0x000000000110ac10 ***
======= Backtrace: =========
/lib/x86_64-linux-gnu/libc.so.6(+0x777e5)[0x7f15737887e5]
/lib/x86_64-linux-gnu/libc.so.6(+0x80dfb)[0x7f1573791dfb]
/lib/x86_64-linux-gnu/libc.so.6(cfree+0x4c)[0x7f157379553c]
./test[0x40fa09]
======= Memory map: ========
...

Changing depth gives different results.

[sancho3]

I just want to add that I tried it with FBC32 on Ubuntu and FBC64 and no crashes.
However changing the depth to 16 or 32 does freeze the program on keypress to exit.

The problem narrows down to the line in font.bi and the load function:

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Get fntimg,(wholewide,0)-(wholewide+wide(i)-1,size-1),Char(i)

It looks like the get command can get from fntimg but often tries to write out of bounds in char(i).

In the font.load function where char(x) is imagecreated, it is done with height = size -1. That should actuallyl be size.
Making that change seems to prevent the freezing I see.

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			Char(i)=ImageCreate(wide(i),size)
			CharItalic(i)=ImageCreate(wide(i)+2,size)
			wholewide+=wide(i)
		Next
		Char(102)=ImageCreate(Wide(64),size)
		CharItalic(102)=ImageCreate(Wide(64)+2,size)
		Char(103)=ImageCreate(Wide(31),size)
		CharItalic(103)=ImageCreate(Wide(31)+2,size)

[thebigh]

Nice! That is some impressive detective work.Now I know what the problem is, and that I am not going insane. Thanks a lot for the help.


EDIT: I believe I have found another small bug. Line 486, in the function TFont.Length, should read

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	For i As Integer=0 To Len(text)-1