gecko-dev/gfx/thebes/gfxFT2Utils.cpp

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4.7 KiB
C++

/* -*- Mode: C++; tab-width: 20; indent-tabs-mode: nil; c-basic-offset: 2 -*-
* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
#include "gfxFT2FontBase.h"
#include "gfxFT2Utils.h"
#include "mozilla/Likely.h"
#ifdef HAVE_FONTCONFIG_FCFREETYPE_H
# include <fontconfig/fcfreetype.h>
#endif
#include "ft2build.h"
#include FT_MULTIPLE_MASTERS_H
#include "prlink.h"
uint32_t gfxFT2LockedFace::GetGlyph(uint32_t aCharCode) {
if (MOZ_UNLIKELY(!mFace)) return 0;
#ifdef HAVE_FONTCONFIG_FCFREETYPE_H
// FcFreeTypeCharIndex will search starting from the most recently
// selected charmap. This can cause non-determistic behavior when more
// than one charmap supports a character but with different glyphs, as
// with older versions of MS Gothic, for example. Always prefer a Unicode
// charmap, if there is one. (FcFreeTypeCharIndex usually does the
// appropriate Unicode conversion, but some fonts have non-Roman glyphs
// for FT_ENCODING_APPLE_ROMAN characters.)
if (!mFace->charmap || mFace->charmap->encoding != FT_ENCODING_UNICODE) {
FT_Select_Charmap(mFace, FT_ENCODING_UNICODE);
}
return FcFreeTypeCharIndex(mFace, aCharCode);
#else
return FT_Get_Char_Index(mFace, aCharCode);
#endif
}
typedef FT_UInt (*GetCharVariantFunction)(FT_Face face, FT_ULong charcode,
FT_ULong variantSelector);
uint32_t gfxFT2LockedFace::GetUVSGlyph(uint32_t aCharCode,
uint32_t aVariantSelector) {
MOZ_ASSERT(aVariantSelector, "aVariantSelector should not be NULL");
if (MOZ_UNLIKELY(!mFace)) return 0;
// This function is available from FreeType 2.3.6 (June 2008).
static CharVariantFunction sGetCharVariantPtr = FindCharVariantFunction();
if (!sGetCharVariantPtr) return 0;
#ifdef HAVE_FONTCONFIG_FCFREETYPE_H
// FcFreeTypeCharIndex may have changed the selected charmap.
// FT_Face_GetCharVariantIndex needs a unicode charmap.
if (!mFace->charmap || mFace->charmap->encoding != FT_ENCODING_UNICODE) {
FT_Select_Charmap(mFace, FT_ENCODING_UNICODE);
}
#endif
return (*sGetCharVariantPtr)(mFace, aCharCode, aVariantSelector);
}
gfxFT2LockedFace::CharVariantFunction
gfxFT2LockedFace::FindCharVariantFunction() {
// This function is available from FreeType 2.3.6 (June 2008).
PRLibrary* lib = nullptr;
CharVariantFunction function = reinterpret_cast<CharVariantFunction>(
PR_FindFunctionSymbolAndLibrary("FT_Face_GetCharVariantIndex", &lib));
if (!lib) {
return nullptr;
}
FT_Int major;
FT_Int minor;
FT_Int patch;
FT_Library_Version(mFace->glyph->library, &major, &minor, &patch);
// Versions 2.4.0 to 2.4.3 crash if configured with
// FT_CONFIG_OPTION_OLD_INTERNALS. Presence of the symbol FT_Alloc
// indicates FT_CONFIG_OPTION_OLD_INTERNALS.
if (major == 2 && minor == 4 && patch < 4 &&
PR_FindFunctionSymbol(lib, "FT_Alloc")) {
function = nullptr;
}
// Decrement the reference count incremented in
// PR_FindFunctionSymbolAndLibrary.
PR_UnloadLibrary(lib);
return function;
}
/*static*/
void gfxFT2Utils::GetVariationAxes(const FT_MM_Var* aMMVar,
nsTArray<gfxFontVariationAxis>& aAxes) {
MOZ_ASSERT(aAxes.IsEmpty());
if (!aMMVar) {
return;
}
aAxes.SetCapacity(aMMVar->num_axis);
for (unsigned i = 0; i < aMMVar->num_axis; i++) {
const auto& a = aMMVar->axis[i];
gfxFontVariationAxis axis;
axis.mMinValue = a.minimum / 65536.0;
axis.mMaxValue = a.maximum / 65536.0;
axis.mDefaultValue = a.def / 65536.0;
axis.mTag = a.tag;
axis.mName = a.name;
aAxes.AppendElement(axis);
}
}
/*static*/
void gfxFT2Utils::GetVariationInstances(
gfxFontEntry* aFontEntry, const FT_MM_Var* aMMVar,
nsTArray<gfxFontVariationInstance>& aInstances) {
MOZ_ASSERT(aInstances.IsEmpty());
if (!aMMVar) {
return;
}
hb_blob_t* nameTable =
aFontEntry->GetFontTable(TRUETYPE_TAG('n', 'a', 'm', 'e'));
if (!nameTable) {
return;
}
aInstances.SetCapacity(aMMVar->num_namedstyles);
for (unsigned i = 0; i < aMMVar->num_namedstyles; i++) {
const auto& ns = aMMVar->namedstyle[i];
gfxFontVariationInstance inst;
nsresult rv =
gfxFontUtils::ReadCanonicalName(nameTable, ns.strid, inst.mName);
if (NS_FAILED(rv)) {
continue;
}
inst.mValues.SetCapacity(aMMVar->num_axis);
for (unsigned j = 0; j < aMMVar->num_axis; j++) {
gfxFontVariationValue value;
value.mAxis = aMMVar->axis[j].tag;
value.mValue = ns.coords[j] / 65536.0;
inst.mValues.AppendElement(value);
}
aInstances.AppendElement(inst);
}
hb_blob_destroy(nameTable);
}