Previously, it was a float32, which obviously has 32 bits of state. Not
all of that 32 bit state space is meaningful, since NaN has multiple bit
representations. The underlying file format field (of type "Fixed" or
16.16 fixed point) is also 32 bits of state
(https://docs.microsoft.com/en-us/typography/opentype/spec/post).
Therefore, converting from 32 bit fixed point to 32 bit floating point
can be lossy. Instead, use 64 bit floating point. 53 significand bits
can losslessly represent all possible 16.16 fixed point values.
Using float64 is also arguably more Go-like, as the default type for the
ideal constant 0.5 is float64, not float32.
Change-Id: I5abe7979a020af2ac4784d6c2723ab8e39e38e34
Reviewed-on: https://go-review.googlesource.com/c/149837
Reviewed-by: Denys Smirnov <denis.smirnov.91@gmail.com>
Reviewed-by: Nigel Tao <nigeltao@golang.org>
Currently the library only parses the version in PostScript table.
However use cases such as PDF document processing requires this
information to be exposed.
CL parses a minimal set of the fields from the PostScript table
and exposes it via new PostTable method.
Change-Id: Ia86eecea9f5aaf557c7e4737f2474966aa30cff2
Reviewed-on: https://go-review.googlesource.com/c/145797
Reviewed-by: Nigel Tao <nigeltao@golang.org>
This change renames the example to follow correct naming convention,
as documented at https://godoc.org/testing#hdr-Examples. As a result,
it shows up in godoc.
This issue was caught and reported by vet:
$ go vet golang.org/x/image/font/sfnt
# golang.org/x/image/font/sfnt_test
font/sfnt/example_test.go:19: ExampleRasterizeGlyph refers to unknown identifier: RasterizeGlyph
Fixesgolang/go#28684
Change-Id: I2749c638c5f3ed15e4db0448bc7a5e2c12c056e5
Reviewed-on: https://go-review.googlesource.com/c/148576
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Currently, the library produces a parsing error when the font
contains a PostScript table of version 1.0.
CL adds this version to the validation code and implements a glyph
name lookup for it.
Change-Id: Id4999d8b252e5c2d8e897f637ba31270336cfe9a
Reviewed-on: https://go-review.googlesource.com/c/146080
Reviewed-by: Nigel Tao <nigeltao@golang.org>
The library assumes the hmtx size to be equal to 2*nGlyph + 2*nHm,
which is a simplification of 4*nHm + 2*(nGlyph-nHm) as described
in the spec. However, fonts seen in the wild sometimes omit the
second term (left side bearings), making validation to fail.
CL fixes the validation code by allowing to omit the second term.
Fixesgolang/go#28379
Change-Id: I2293e498e72f95e5fe08c2b375ea7b020d06cde3
Reviewed-on: https://go-review.googlesource.com/c/144080
Reviewed-by: Nigel Tao <nigeltao@golang.org>
Library assumes that OS/2 header size is at least 96 bytes,
which is not the case for fonts with OS/2 table version <= 1.
This CL adds a version test and handles the legacy header.
Fixesgolang/go#28339
Change-Id: I79bd8f8bbf262c1caaf4e66888446159b5e4fb43
Reviewed-on: https://go-review.googlesource.com/c/144079
Reviewed-by: Nigel Tao <nigeltao@golang.org>
Reviewed-by: Elias Naur <elias.naur@gmail.com>
This CL adds the type Face that implements the font.Face interface.
This CL also adds tests using gofont/goregular as an input font, using
github.com/golang/freetype/truetype as reference values.
Updates golang/go#22451.
Change-Id: I2a6945309331b251ec2ddec95b6e809ad10aa116
Reviewed-on: https://go-review.googlesource.com/73870
Reviewed-by: Nigel Tao <nigeltao@golang.org>
Also add tests for the Noto proprietary fonts. Prior to this commit,
NotoColorEmoji.ttf was unsupported. It's still not well supported, but
the error message returned is now more informative.
Change-Id: I61a3301d7f2458a4b838eb1de7a73d6472e3486f
Reviewed-on: https://go-review.googlesource.com/43694
Reviewed-by: David Crawshaw <crawshaw@golang.org>
A future commit will actually use subtables past the first one, but for
now, ignore them instead of failing on their presence.
Also add tests for the DejaVu proprietary fonts. Prior to this commit,
DejaVuSans-ExtraLight.ttf was unsupported.
Change-Id: Ic78a59c5ab30e4091efa2a04b89b12cb786157db
Reviewed-on: https://go-review.googlesource.com/42192
Reviewed-by: David Crawshaw <crawshaw@golang.org>
The underlying font format's Y axis increases up. The Go standard
graphics libraries' Y axis increases down. This change makes the Go API
consistent with the other Go libraries.
Also change Segment.Args from [6]fixed.Int26_6 to [3]fixed.Point26_6 to
emphasize that the Args are consistent with other fixed.Point26_6 use.
Change-Id: Idd7b89eb4d86890dea477ac2ef96ff8f6b1dee8d
Reviewed-on: https://go-review.googlesource.com/39072
Reviewed-by: David Crawshaw <crawshaw@golang.org>
Bigelow & Holmes have prepared new versions of the Go Fonts. The version
numbers have changed from 2.004 to 2.008. ChangeLog:
* New! 2 new fonts, bringing the total to 12: Go Smallcaps and Go
Smallcaps Italic.
* New! U+FFFD REPLACEMENT CHARACTER glyph added.
* U+00C5 LATIN CAPITAL LETTER A WITH RING ABOVE ring tweaked.
* U+00F0 LATIN SMALL LETTER ETH glyph lightened.
* Superfluous U+0005 <control> glyph removed.
* Split integral, chart draw, block, shade and related glyphs now span
the full height and have fewer seams when tiled.
* Raised most capital letter diacritics and some lowercase diacritics.
* Mono character widths fixed to be uniform.
* Underline position adjusted.
* SFNT glyph order and cmap table optimized.
* SFNT glyph names (post table) regularized, consistent with the AGLFN.
* ttfautohint upgraded to the latest version, from 1.5 to 1.6.
Change-Id: I0985f07d58b984010199dd723ccdf5892ee59c78
Reviewed-on: https://go-review.googlesource.com/38870
Reviewed-by: Rob Pike <r@golang.org>
Recent commits (probably 792d36e1 "support TrueType compound glyphs" and
1995ed1a "support TrueType glyph transformations") let us decode all the
glyphs in the Adobe TrueType fonts, but I forgot to update the test
coverage in those commits.
Change-Id: I7b135005cd67082f84aee16d296debdedcc9488e
Reviewed-on: https://go-review.googlesource.com/38281
Reviewed-by: David Crawshaw <crawshaw@golang.org>
This will lessen the diff in a subsequent commit, which introduces a
call stack.
Change-Id: I478857675f47b53e6bd3ee270087a00b9d1d4d34
Reviewed-on: https://go-review.googlesource.com/38279
Reviewed-by: Nigel Tao <nigeltao@golang.org>
The format is relatively complicated but rarely seen. It doesn't seem
worth the effort. Ignoring it is what Microsoft Windows and FreeType do.
Change-Id: I4415bd591c832650066de1d4e035b20a7230a4da
Reviewed-on: https://go-review.googlesource.com/38273
Reviewed-by: David Crawshaw <crawshaw@golang.org>
Also add tests for Apple proprietary fonts.
Change-Id: I5ce8efa2397bb01c5255d956a77c955ba1383105
Reviewed-on: https://go-review.googlesource.com/38272
Reviewed-by: David Crawshaw <crawshaw@golang.org>
This lets us load a glyph at e.g. 12 pixels per em.
Change-Id: I048b3db89af8670782953a8361afe0e6373df9b0
Reviewed-on: https://go-review.googlesource.com/37175
Reviewed-by: David Crawshaw <crawshaw@golang.org>
The latest version of that TTF file fixes the inconsistency between the
TTF and OTF versions.
Change-Id: I0b86f6ddc3f0326e538bdd18fe097be9ad8533ae
Reviewed-on: https://go-review.googlesource.com/37173
Reviewed-by: David Crawshaw <crawshaw@golang.org>
This is based on the post table in the sfnt file.
Change-Id: I11f7a9bd9024cfc8f92adc5abb4d5356521f0df7
Reviewed-on: https://go-review.googlesource.com/36972
Reviewed-by: David Crawshaw <crawshaw@golang.org>
Two recent commits ("proprietary fonts" and "cmap format 12") each
passed all of its own tests, but the combination wasn't tested until
both were submitted.
Change-Id: Ic4c2ae8deb1e4623ca5543672dc46d55bfce91a4
Reviewed-on: https://go-review.googlesource.com/36372
Reviewed-by: David Crawshaw <crawshaw@golang.org>
