1""" 2Interpolate OpenType Layout tables (GDEF / GPOS / GSUB). 3""" 4from fontTools.ttLib import TTFont 5from fontTools.varLib import models, VarLibError, load_designspace, load_masters 6from fontTools.varLib.merger import InstancerMerger 7import os.path 8import logging 9from copy import deepcopy 10from pprint import pformat 11 12log = logging.getLogger("fontTools.varLib.interpolate_layout") 13 14 15def interpolate_layout(designspace, loc, master_finder=lambda s:s, mapped=False): 16 """ 17 Interpolate GPOS from a designspace file and location. 18 19 If master_finder is set, it should be a callable that takes master 20 filename as found in designspace file and map it to master font 21 binary as to be opened (eg. .ttf or .otf). 22 23 If mapped is False (default), then location is mapped using the 24 map element of the axes in designspace file. If mapped is True, 25 it is assumed that location is in designspace's internal space and 26 no mapping is performed. 27 """ 28 if hasattr(designspace, "sources"): # Assume a DesignspaceDocument 29 pass 30 else: # Assume a file path 31 from fontTools.designspaceLib import DesignSpaceDocument 32 designspace = DesignSpaceDocument.fromfile(designspace) 33 34 ds = load_designspace(designspace) 35 log.info("Building interpolated font") 36 37 log.info("Loading master fonts") 38 master_fonts = load_masters(designspace, master_finder) 39 font = deepcopy(master_fonts[ds.base_idx]) 40 41 log.info("Location: %s", pformat(loc)) 42 if not mapped: 43 loc = {name: ds.axes[name].map_forward(v) for name,v in loc.items()} 44 log.info("Internal location: %s", pformat(loc)) 45 loc = models.normalizeLocation(loc, ds.internal_axis_supports) 46 log.info("Normalized location: %s", pformat(loc)) 47 48 # Assume single-model for now. 49 model = models.VariationModel(ds.normalized_master_locs) 50 assert 0 == model.mapping[ds.base_idx] 51 52 merger = InstancerMerger(font, model, loc) 53 54 log.info("Building interpolated tables") 55 # TODO GSUB/GDEF 56 merger.mergeTables(font, master_fonts, ['GPOS']) 57 return font 58 59 60def main(args=None): 61 """Interpolate GDEF/GPOS/GSUB tables for a point on a designspace""" 62 from fontTools import configLogger 63 import argparse 64 import sys 65 66 parser = argparse.ArgumentParser( 67 "fonttools varLib.interpolate_layout", 68 description=main.__doc__, 69 ) 70 parser.add_argument('designspace_filename', metavar='DESIGNSPACE', 71 help="Input TTF files") 72 parser.add_argument('locations', metavar='LOCATION', type=str, nargs='+', 73 help="Axis locations (e.g. wdth=120") 74 parser.add_argument('-o', '--output', metavar='OUTPUT', 75 help="Output font file (defaults to <designspacename>-instance.ttf)") 76 parser.add_argument('-l', '--loglevel', metavar='LEVEL', default="INFO", 77 help="Logging level (defaults to INFO)") 78 79 80 args = parser.parse_args(args) 81 82 if not args.output: 83 args.output = os.path.splitext(args.designspace_filename)[0] + '-instance.ttf' 84 85 configLogger(level=args.loglevel) 86 87 finder = lambda s: s.replace('master_ufo', 'master_ttf_interpolatable').replace('.ufo', '.ttf') 88 89 loc = {} 90 for arg in args.locations: 91 tag,val = arg.split('=') 92 loc[tag] = float(val) 93 94 font = interpolate_layout(args.designspace_filename, loc, finder) 95 log.info("Saving font %s", args.output) 96 font.save(args.output) 97 98 99if __name__ == "__main__": 100 import sys 101 if len(sys.argv) > 1: 102 sys.exit(main()) 103 import doctest 104 sys.exit(doctest.testmod().failed) 105