FXY File Format

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Introduction

PAA layout of a font

The OFP and ArmA engines use a limited set of bit mapped fonts developed by Bohemia Interactive for the engine. They are bitmaps and each glyph within is treated as a texture.

A character set (such as Ascii) is a series of 'glyphs' (characters) where any one of these characters is always identified by the same index value. For example the letter A is always hex 41 and so on. Regardless of the font set employed, the character set within it, is set-in-concrete. Hex 41 always renders a glyph that 'looks like' the letter A. Be it bold, italic, or fills the entire screen, it is the letter 'A'.

The character set for all BI fonts in OFP is different for each language version. For Western languages it approximates US-Ascii codepage 437. In ArmA Unicode is used for fonts.

A font set is a collection of displayable characters (termed glyphs) that have a common appearance. Eg all glyphs in THIS set are bold, or all the glyphs are italic, all the glyphs are Times Roman (seriffed).

Individual font sets exist for Tahoma, Garamond, and so on.

The glyphs within these sets, are contained in .paa files. Generally, the entire font set = one, paa file.

And, because these are bitmapped fonts, eg fixed dimensions, non-scaleable, there are unique font sets, for, unique sizes.

For example, in Resistance engine, the popular Tahoma font is in three different font sets. 24 point, 36 point, 48 point.

A 'point' approximates 1/72th of an inch. Thus the Tahoma fonts available (for Resistance) are approximately a third, a half, and two thirds of an inch tall when displayed.

Description

An fxy file is the 'character set' index. It is, the codepage.

An fxy file is implicitly associated with one or more paa files within the same folder. The fxy file is the header entry for these files, it describes the position in the paa file and the size to be rendered on screen, for a 'glyph'.

Association of files between fxy and paa is implicit. The CourierNewB64.fxy is implicitly associated with the CourierNewB64-xx.paa file(s). xx indicating one of several CourierNewB64 paa's.

Struct

The fxy is a contiguous series of 12 byte entries. For OFP, the typically contain 224 entries, because the first 32 indexes of an Ascii codepage are unprintable, which leaves 256-32= 224. ArmA fxy's have 1088 entries, as each font supports both Western European, Eastern European and Cyrillic characters.

Since ArmA, the fxy files contain 8 byte prefix (magic 32b value followed by a font version number, which is 0x101 for ArmA).

Each entry can be described in the following struct

struct FxyEntry {
  ushort  CharCode;     // 0x21 = 'A' <<< see note
  ushort  PaaFileNumber; // 01
  ushort  X,Y            // Top-left Corner of char on the texture in pixels
  ushort  Width,Height;  // Size of the char on the texture in pixels
  /* since ArmA */ ushort KerningWidth; // width used to determine this character spacing
};

CharCode

ASCII (OFP) or Unicode (ArmA) code of the character. While OFP fonts released with the game contain continuous range of characters 0x20-0xff, it is not necessary for each font to implement it. Any font file can skip any characters not supported by it.

PaaFileNumber -number of texture file: This is simply a convenience to allow large fonts to be spread across several paa's.

font name is "CourierNewB64" 
Fxy file is "CourierNewB64.fxy", 
First texture file is "CourierNewB64-01.paa", 
second is "CourierNewB64-02.paa".

Usage

This example using the new font name in a ArmA description.ext.

class RscText
{
       type = CT_STATIC;
       idc = -1;
       style = ST_LEFT;
       colorBackground[] = {0, 0, 0, 0};
       colorText[] = {1, 1, 1, 1};
       font = Bitstream;
       sizeEx = 0.04;
};

Paa Content

Resistance

.paa files used for the font must be in 8080 format: (Alpha luminosity)

8bit - Brightness (all with 255 value - "white");
8bit - Alpha (255 for character, 0 for space);

ArmA

Arma Glyph files (paa) are formatted in DXT5 compressed textures. Using the TAGG labelling, they must additionally specify

Avg Color: any
Max Color: always FFFFFFFF
AlphaFlag: 1

Available Fonts

Resistance and CWC

AudreysHand 48pt Italic
AudreysHand 48pt Bold
CourierNew Bold 64pt
Garamond 64
Steelfish bold 64 and 128 pt
SteelfishCE bold 64 
Tahoma 24/36/48 bold

Elite

Arial Bold 7,8,10,11,12 pt
Arial Italic 9,13,18,48
CourierNew 9pt
Hel67-CM 10,11 pt
HelvCondLight 8,9,10 pt
Helvetica-Narrow 11pt
Helvetica-Narrow Bold 8pt
Helvetica37-CondensedThin bold 10pt
Helvetica57-Condensed 10,13,16pt
Helvetica57-Condensed 9 ,13,14 pt Bold 
Helvetica67-Condensed 10,11,9pt Medium
HelveticaNarrow 10,11pt
HelveticaNarrow bold 10,13,18,22
HelveticaNeue 10,11,12,13,14,22
HelveticaNeue  Bold 22 B22-01.paa
LucidaConsole Bold 11,8
MSS Bold 9
System 10pt
System 10pt Bold
Tahoma 10,11,12,14,16,20,21pt
Tahoma 5,6,7,9,10,11,12,13,14,16,20,21 pt bold
Tahoma 12pt Bold Italic

ArmA

Arial Bold 7->24 pt
BitStreamVersans bold 7->20, 22, 28 pt
Zeppelin32 12->20,22,28 pt
Zeppelin33 12->20,22,28 pt
Zeppelin33 12->20,22,28 pt italic