MyouProject/pixie
3
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions

Speed up CFF font reading by like x100.

Browse source
This commit is contained in:
treeform 2021-10-06 11:56:35 -07:00
parent a4fd8e1f62
commit 668958e373
1 changed files with 17 additions and 8 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

25
src/pixie/fontformats/opentype.nim
View file

@ -364,7 +364,7 @@ type
stringIndex: seq[string] stringIndex: seq[string]
globalSubrIndex: seq[string] globalSubrIndex: seq[string]
topDict: CFFTopDict topDict: CFFTopDict
charIndex: seq[string] charIndex: seq[(int, int)]
isCID: bool isCID: bool
OpenType* = ref object OpenType* = ref object
@ -808,7 +808,7 @@ proc parseKernTable(buf: string, offset: int): KernTable =
else: else:
failUnsupported("Kern version") failUnsupported("Kern version")
proc parseCFFIndex(buf: string, start: var int, stripZero = false): seq[string] = proc parseCFFIndexOffsets(buf: string, start: var int, stripZero = false): seq[(int, int)] =
proc getOffset(buf: string, offset, offSize: int): int = proc getOffset(buf: string, offset, offSize: int): int =
var v = 0 var v = 0
@ -838,12 +838,19 @@ proc parseCFFIndex(buf: string, start: var int, stripZero = false): seq[string]
# * binary strings # * binary strings
# * null terminate ascii strings # * null terminate ascii strings
for i in 0 ..< offsets.len - 1: for i in 0 ..< offsets.len - 1:
var value = buf[objectOffset + offsets[i] ..< objectOffset + offsets[i + 1]] var
a = objectOffset + offsets[i]
b = objectOffset + offsets[i + 1]
if stripZero: if stripZero:
value = value[0..^1] # ignore 0 at the end dec b # ignore 0 at the end
result.add(value) result.add((a, b))
start = endOffset start = endOffset
proc parseCFFIndex(buf: string, start: var int, stripZero = false): seq[string] =
let offsets = parseCFFIndexOffsets(buf, start, stripZero)
for (a, b) in offsets:
result.add(buf[a ..< b])
const cffStandardStrings = [ const cffStandardStrings = [
".notdef", "space", "exclam", "quotedbl", "numbersign", "dollar", "percent", ".notdef", "space", "exclam", "quotedbl", "numbersign", "dollar", "percent",
"ampersand", "quoteright", "parenleft", "parenright", "asterisk", "plus", "ampersand", "quoteright", "parenleft", "parenright", "asterisk", "plus",
@ -1613,7 +1620,7 @@ proc parseCFFTable(buf: string, offset: int, maxp: MaxpTable): CFFTable =
# # buf, offset + result.topDict.charset, nGlyphs, result.stringIndex.objects) # # buf, offset + result.topDict.charset, nGlyphs, result.stringIndex.objects)
var start = offset + result.topDict.charStrings var start = offset + result.topDict.charStrings
result.charIndex = buf.parseCFFIndex(start) result.charIndex = buf.parseCFFIndexOffsets(start)
# proc parseLangSys(buf: string, offset: int): LangSys = # proc parseLangSys(buf: string, offset: int): LangSys =
# var i = offset # var i = offset
@ -2375,8 +2382,10 @@ proc parseGlyfGlyph(opentype: OpenType, glyphId: uint16): Path =
parseGlyphPath(opentype.buf, i, numberOfContours) parseGlyphPath(opentype.buf, i, numberOfContours)
proc parseCffGlyph(opentype: OpenType, glyphId: uint16): Path = proc parseCffGlyph(opentype: OpenType, glyphId: uint16): Path =
let cff = opentype.cff let
let charstring = cff.charIndex[glyphId] cff = opentype.cff
(a, b) = cff.charIndex[glyphId]
charstring = opentype.buf[a ..< b]
return cff.parseCFFCharstring(charstring, glyphId.int) return cff.parseCFFCharstring(charstring, glyphId.int)
proc parseGlyph(opentype: OpenType, rune: Rune): Path {.inline.} = proc parseGlyph(opentype: OpenType, rune: Rune): Path {.inline.} =