Reply to Glyph Designer Binary Export Format on Mon, 26 Oct 2015 09:21:54 GMT

tom — Mon, 26 Oct 2015 09:21:54 GMT

As well as outputting the data as a text based file, there is also a binary based file format.

Header

The first three bytes of the header are the file identifier and are always set to 66, 77, 70 (BMF). The fourth byte is the version which is currently 3.

After the header are a number of blocks based on the tags described above.

Block type 1: info

Field	Size	Type	Pos	Comment
fontsize	2	int	0
bitField	1	bits	2	bit 0:smooth bit 1:unicode bit 2:italic bit 3:bold bit 4:fixedHeight bits 5-7:reservered
charSet	1	uint	3
stretchH	2	uint	4
aa	1	uint	6
paddingUp	2	uint	7
paddingRight	1	uint	8
paddingDown	1	uint	9
paddingLeft	1	uint	10
spacingHoriz	1	uint	11
spacingVert	1	uint	12
outline	1	uint	13
fontName	n+1	string	14	null terminated string with length n

Block type 2: common

Field	Size	Type	Pos	Comment
lineHeight	2	uint	0
base	2	uint	2
scaleW	2	uint	4
scaleH	2	uint	6
pages	2	uint	8
bitField	1	bits	10	bits 0-6:reserved, bit 7:packed

Block type 3: pages

Field	Size	Type	Pos	Comment
pageNames	p*(n+1)	strings	0	null terminated strings, each with length n

Block type 4: chars

Field	Size	Type	Pos	Comment
id	4	uint	0+c*20	these fields are repeated until all characters have been described
x	2	uint	4+c*20
y	2	uint	6+c*20
width	2	uint	8+c*20
height	2	uint	10+c*20
xoffset	2	uint	12+c*20
yoffset	2	uint	14+c*20
xadvance	2	uint	16+c*20
page	1	uint	18+c*20
chnl	1	uint	19+c*20

The number of characters in the file can be calculated by taking the size of the block and dividing it with the size of the charInfo structure, i.e. numChars = charsBlock.blockSize/20