OpenType Collections—Redux

As described in last month's article, our tools engineer developed two Python scripts for assembling and disassembling 'sfnt' collections, both of which operate on TrueType-based source fonts to produce a traditional TrueType Collection (TTC) font or to break apart one, but also operate on CFF-based source fonts to produce a new font species known as an OpenType Collection (OTC).

The purpose of this follow up article is to convey the news that these scripts have been tweaked slightly, and have been included in a new version of AFDKO that was released on 2014-02-18 as Build 61250. One of the benefits of the integration with AFDKO is that the tools are now easier to run, as a simple command.

The following is a demonstration:

%otf2otc-t 'cmap'=0-o LogoLineStd.ttc LogoLineStd-Light.otf LogoLineStd-Medium.otf LogoLineStd-Bold.otf LogoLineStd-Ultra.otf

Input fonts: ['LogoLineStd-Light.otf', 'LogoLineStd-Medium.otf', 'LogoLineStd-Bold.otf', 'LogoLineStd-Ultra.otf']

Output font: LogoLineStd.ttc

Shared tables: ['GSUB', 'cmap', 'maxp', 'post', 'vhea']

Un-shared tables: ['BASE', 'CFF ', 'GPOS', 'OS/2', 'VORG', 'head', 'hhea', 'hmtx', 'name', 'vmtx']

Done

(Note: The version of this script in AFDKO Build 61250 transposes the reporting of the shared and unshared tables, and what is shown above is based on a corrected version that can be downloaded here, then installed into the "Tools/SharedData/FDKScripts/" subdirectory of AFDKO, replacing the version that is included in Build 61250.)

Note how its output makes the table-share-check.pl script that I introduced in the previous article somewhat obsolete, by conveniently reporting the (completely) shared and unshared tables. However, that script is not completely useless, because it still reports (completely) shared and unshared tables based on either otc2otf-r and spot-T output, though I suggest downloading the latest version. Below is a demonstration:

%otc2otf-r LogoLineStd.ttc | table-share-check.pl

Shared Tables: GSUB, cmap, maxp, post, vhea

Unshared Tables: BASE, CFF , GPOS, OS/2, VORG, head, hhea, hmtx, name, vmtx

%spot-T LogoLineStd.ttc | table-share-check.pl

Shared Tables: GSUB, cmap, maxp, post, vhea

Unshared Tables: BASE, CFF , GPOS, OS/2, VORG, head, hhea, hmtx, name, vmtx

The above paragraph brings up the last point for this article, which are two behavior changes in the otc2otf script. First, the script supports a new "-r" command-line option that reports table offsets, checksums, and lengths, and the extent to which they are shared on a per-font instance basis, as exemplified below:

%otc2otf-r LogoLineStd.ttc

Input font: LogoLineStd.ttc

font 0 offset: 28/0x0000001C. LogoLineStd-Light.otf

BASE offset: 0x0000040C, checksum: 0x1BA818DF, length: 0x000000E8

CFF offset: 0x000005D8, checksum: 0x1715F501, length: 0x00007D10

GPOS offset: 0x00020602, checksum: 0x1646F381, length: 0x000009FE

GSUB offset: 0x00022C14, checksum: 0x9B0A9A80, length: 0x00000926

OS/2 offset: 0x0002353A, checksum: 0x7529D1A9, length: 0x00000060

VORG offset: 0x000236BA, checksum: 0x0D0B3CF9, length: 0x00000050

cmap offset: 0x000237FA, checksum: 0xA1E5EC81, length: 0x00000D88

head offset: 0x00024582, checksum: 0xFC3D0459, length: 0x00000036

hhea offset: 0x00024624, checksum: 0x0B4203A3, length: 0x00000024

hmtx offset: 0x00024690, checksum: 0xC1D77DDB, length: 0x0000039C

maxp offset: 0x00025500, checksum: 0x01A15000, length: 0x00000006

name offset: 0x00025506, checksum: 0xE1EDF545, length: 0x00000797

post offset: 0x00027350, checksum: 0xFFB80032, length: 0x00000020

vhea offset: 0x00027370, checksum: 0x09C7136C, length: 0x00000024

vmtx offset: 0x00027394, checksum: 0xC3E2E642, length: 0x00000632

font 1 offset: 280/0x00000118. LogoLineStd-Medium.otf

BASE offset: 0x000004F4, checksum: 0x1B8E18D8, length: 0x000000E4

CFF offset: 0x000082E8, checksum: 0xC61D636F, length: 0x000080F7

GPOS offset: 0x00021000, checksum: 0xF654DD9C, length: 0x000009AE

GSUB offset: 0x00022C14, already seen

OS/2 offset: 0x0002359A, checksum: 0x75F1D5A9, length: 0x00000060

VORG offset: 0x0002370A, checksum: 0x0D0B3D27, length: 0x00000050

cmap offset: 0x000237FA, already seen

head offset: 0x00024582, already seen

hhea offset: 0x00024624, already seen

hmtx offset: 0x00024A2C, checksum: 0xBCAA7581, length: 0x0000039C

maxp offset: 0x00025500, already seen

name offset: 0x00025C9D, checksum: 0xDB4FBB0C, length: 0x0000079E

post offset: 0x00027350, already seen

vhea offset: 0x00027370, already seen

vmtx offset: 0x000279C6, checksum: 0xC2BDD81E, length: 0x00000632

font 2 offset: 532/0x00000214. LogoLineStd-Bold.otf

BASE offset: 0x000004F4, already seen

CFF offset: 0x000103DF, checksum: 0x31BA2CEC, length: 0x000080E4

GPOS offset: 0x000219AE, checksum: 0xC9E3B98B, length: 0x00000922

GSUB offset: 0x00022C14, already seen

OS/2 offset: 0x000235FA, checksum: 0x76B9D7C9, length: 0x00000060

VORG offset: 0x0002375A, checksum: 0x0D0B3D17, length: 0x00000050

cmap offset: 0x000237FA, already seen

head offset: 0x000245B8, checksum: 0xFC43045B, length: 0x00000036

hhea offset: 0x00024648, checksum: 0x0B4703A2, length: 0x00000024

hmtx offset: 0x00024DC8, checksum: 0xAEC76614, length: 0x0000039C

maxp offset: 0x00025500, already seen

name offset: 0x0002643B, checksum: 0x959E0945, length: 0x00000787

post offset: 0x00027350, already seen

vhea offset: 0x00027370, already seen

vmtx offset: 0x00027FF8, checksum: 0xC14AC4BE, length: 0x00000632

font 3 offset: 784/0x00000310. LogoLineStd-Ultra.otf

BASE offset: 0x000004F4, already seen

CFF offset: 0x000184C3, checksum: 0xA164D643, length: 0x0000813F

GPOS offset: 0x000222D0, checksum: 0xD5BEBF8B, length: 0x00000944

GSUB offset: 0x00022C14, already seen

OS/2 offset: 0x0002365A, checksum: 0x7781D8C9, length: 0x00000060

VORG offset: 0x000237AA, checksum: 0x0D0A3D12, length: 0x00000050

cmap offset: 0x000237FA, already seen

head offset: 0x000245EE, checksum: 0xFC3D045B, length: 0x00000036

hhea offset: 0x0002466C, checksum: 0x0B4103A2, length: 0x00000024

hmtx offset: 0x00025164, checksum: 0xAA6F5FBD, length: 0x0000039C

maxp offset: 0x00025500, already seen

name offset: 0x00026BC2, checksum: 0x01BFFDAC, length: 0x0000078E

post offset: 0x00027350, already seen

vhea offset: 0x00027370, already seen

vmtx offset: 0x0002862A, checksum: 0xC039BB2B, length: 0x00000632

Done

Second, this script now reports which fonts are created when breaking apart an 'sfnt' collection (the "-w" command-line option as described in the previous article is no longer necessary, and is thus no longer supported):

%otc2otf LogoLineStd.ttc

Input font: LogoLineStd.ttc

Output font: LogoLineStd-Light.otf

Output font: LogoLineStd-Medium.otf

Output font: LogoLineStd-Bold.otf

Output font: LogoLineStd-Ultra.otf

Done

As usual, enjoy!