diff options
Diffstat (limited to 'vendor/golang.org/x/image/font/sfnt/postscript.go')
| -rw-r--r-- | vendor/golang.org/x/image/font/sfnt/postscript.go | 12 |
1 files changed, 12 insertions, 0 deletions
diff --git a/vendor/golang.org/x/image/font/sfnt/postscript.go b/vendor/golang.org/x/image/font/sfnt/postscript.go index b686e60..2a21997 100644 --- a/vendor/golang.org/x/image/font/sfnt/postscript.go +++ b/vendor/golang.org/x/image/font/sfnt/postscript.go @@ -795,6 +795,18 @@ func (p *psInterpreter) parseNumber() (hasResult bool, err error) { } number, hasResult = int32(u32(p.instructions[1:])), true p.instructions = p.instructions[5:] + // 5177.Type2.pdf section 3.2 "Charstring Number Encoding" says "If the + // charstring byte contains the value 255... [this] number is + // interpreted as a Fixed; that is, a signed number with 16 bits of + // fraction". + // + // TODO: change the psType2CharstringsData.b.segments and + // psInterpreter.argStack data structures to optionally hold fixed + // point values, not just integer values. That's a substantial + // re-design, though. Until then, just round the 16.16 fixed point + // number to the closest integer value. This isn't just "number = + // ((number + 0x8000) >> 16)" because of potential overflow. + number = (number >> 16) + (1 & (number >> 15)) } if hasResult { |