gecko-dev/gfx/thebes/gfxMacFont.cpp
Karl Tomlinson 7ed492d291 b=569770 part 3: provide public access to gfxFontEntry font table cache r=jfkthame
--HG--
extra : rebase_source : ea989eec6d22c0201a58cbe0bb045470e14907f0
2010-12-09 20:28:47 +13:00

434 lines
15 KiB
C++

/* -*- Mode: C++; tab-width: 20; indent-tabs-mode: nil; c-basic-offset: 4 -*-
* ***** BEGIN LICENSE BLOCK *****
* Version: MPL 1.1/GPL 2.0/LGPL 2.1
*
* The contents of this file are subject to the Mozilla Public License Version
* 1.1 (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
* http://www.mozilla.org/MPL/
*
* Software distributed under the License is distributed on an "AS IS" basis,
* WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
* for the specific language governing rights and limitations under the
* License.
*
* The Original Code is Mozilla Corporation code.
*
* The Initial Developer of the Original Code is Mozilla Foundation.
* Portions created by the Initial Developer are Copyright (C) 2006-2010
* the Initial Developer. All Rights Reserved.
*
* Contributor(s):
* Vladimir Vukicevic <vladimir@pobox.com>
* Masayuki Nakano <masayuki@d-toybox.com>
* John Daggett <jdaggett@mozilla.com>
* Jonathan Kew <jfkthame@gmail.com>
*
* Alternatively, the contents of this file may be used under the terms of
* either the GNU General Public License Version 2 or later (the "GPL"), or
* the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
* in which case the provisions of the GPL or the LGPL are applicable instead
* of those above. If you wish to allow use of your version of this file only
* under the terms of either the GPL or the LGPL, and not to allow others to
* use your version of this file under the terms of the MPL, indicate your
* decision by deleting the provisions above and replace them with the notice
* and other provisions required by the GPL or the LGPL. If you do not delete
* the provisions above, a recipient may use your version of this file under
* the terms of any one of the MPL, the GPL or the LGPL.
*
* ***** END LICENSE BLOCK ***** */
#include "gfxMacFont.h"
#include "gfxCoreTextShaper.h"
#include "gfxHarfBuzzShaper.h"
#include "gfxPlatformMac.h"
#include "gfxContext.h"
#include "gfxUnicodeProperties.h"
#include "gfxFontUtils.h"
#include "cairo-quartz.h"
using namespace mozilla;
gfxMacFont::gfxMacFont(MacOSFontEntry *aFontEntry, const gfxFontStyle *aFontStyle,
PRBool aNeedsBold)
: gfxFont(aFontEntry, aFontStyle),
mATSFont(aFontEntry->GetFontRef()),
mCGFont(nsnull),
mFontFace(nsnull),
mScaledFont(nsnull)
{
if (aNeedsBold) {
mSyntheticBoldOffset = 1; // devunit offset when double-striking text to fake boldness
}
mCGFont = ::CGFontCreateWithPlatformFont(&mATSFont);
if (!mCGFont) {
mIsValid = PR_FALSE;
return;
}
// InitMetrics will handle the sizeAdjust factor and set mAdjustedSize
InitMetrics();
if (!mIsValid) {
return;
}
mFontFace = cairo_quartz_font_face_create_for_cgfont(mCGFont);
cairo_status_t cairoerr = cairo_font_face_status(mFontFace);
if (cairoerr != CAIRO_STATUS_SUCCESS) {
mIsValid = PR_FALSE;
#ifdef DEBUG
char warnBuf[1024];
sprintf(warnBuf, "Failed to create Cairo font face: %s status: %d",
NS_ConvertUTF16toUTF8(GetName()).get(), cairoerr);
NS_WARNING(warnBuf);
#endif
return;
}
cairo_matrix_t sizeMatrix, ctm;
cairo_matrix_init_identity(&ctm);
cairo_matrix_init_scale(&sizeMatrix, mAdjustedSize, mAdjustedSize);
// synthetic oblique by skewing via the font matrix
PRBool needsOblique =
(mFontEntry != NULL) &&
(!mFontEntry->IsItalic() &&
(mStyle.style & (FONT_STYLE_ITALIC | FONT_STYLE_OBLIQUE)));
if (needsOblique) {
double skewfactor = (needsOblique ? Fix2X(kATSItalicQDSkew) : 0);
cairo_matrix_t style;
cairo_matrix_init(&style,
1, //xx
0, //yx
-1 * skewfactor, //xy
1, //yy
0, //x0
0); //y0
cairo_matrix_multiply(&sizeMatrix, &sizeMatrix, &style);
}
cairo_font_options_t *fontOptions = cairo_font_options_create();
// turn off font anti-aliasing based on user pref setting
if (mAdjustedSize <=
(gfxFloat)gfxPlatformMac::GetPlatform()->GetAntiAliasingThreshold()) {
cairo_font_options_set_antialias(fontOptions, CAIRO_ANTIALIAS_NONE);
}
mScaledFont = cairo_scaled_font_create(mFontFace, &sizeMatrix, &ctm,
fontOptions);
cairo_font_options_destroy(fontOptions);
cairoerr = cairo_scaled_font_status(mScaledFont);
if (cairoerr != CAIRO_STATUS_SUCCESS) {
mIsValid = PR_FALSE;
#ifdef DEBUG
char warnBuf[1024];
sprintf(warnBuf, "Failed to create scaled font: %s status: %d",
NS_ConvertUTF16toUTF8(GetName()).get(), cairoerr);
NS_WARNING(warnBuf);
#endif
}
if (FontCanSupportHarfBuzz()) {
mHarfBuzzShaper = new gfxHarfBuzzShaper(this);
}
}
gfxMacFont::~gfxMacFont()
{
if (mScaledFont) {
cairo_scaled_font_destroy(mScaledFont);
}
if (mFontFace) {
cairo_font_face_destroy(mFontFace);
}
// this is documented to be safe if mCGFont is null
::CGFontRelease(mCGFont);
}
PRBool
gfxMacFont::InitTextRun(gfxContext *aContext,
gfxTextRun *aTextRun,
const PRUnichar *aString,
PRUint32 aRunStart,
PRUint32 aRunLength,
PRInt32 aRunScript,
PRBool aPreferPlatformShaping)
{
if (!mIsValid) {
NS_WARNING("invalid font! expect incorrect text rendering");
return PR_FALSE;
}
PRBool ok = gfxFont::InitTextRun(aContext, aTextRun, aString,
aRunStart, aRunLength, aRunScript,
static_cast<MacOSFontEntry*>(GetFontEntry())->RequiresAATLayout());
aTextRun->AdjustAdvancesForSyntheticBold(aRunStart, aRunLength);
return ok;
}
void
gfxMacFont::CreatePlatformShaper()
{
mPlatformShaper = new gfxCoreTextShaper(this);
}
PRBool
gfxMacFont::SetupCairoFont(gfxContext *aContext)
{
if (cairo_scaled_font_status(mScaledFont) != CAIRO_STATUS_SUCCESS) {
// Don't cairo_set_scaled_font as that would propagate the error to
// the cairo_t, precluding any further drawing.
return PR_FALSE;
}
cairo_set_scaled_font(aContext->GetCairo(), mScaledFont);
return PR_TRUE;
}
void
gfxMacFont::InitMetrics()
{
mIsValid = PR_FALSE;
::memset(&mMetrics, 0, sizeof(mMetrics));
PRUint32 upem = 0;
// try to get unitsPerEm from sfnt head table, to avoid calling CGFont
// if possible (bug 574368) and because CGFontGetUnitsPerEm does not
// return the true value for OpenType/CFF fonts (it normalizes to 1000,
// which then leads to metrics errors when we read the 'hmtx' table to
// get glyph advances for HarfBuzz, see bug 580863)
const PRUint32 kHeadTableTag = TRUETYPE_TAG('h','e','a','d');
nsAutoTArray<PRUint8,sizeof(HeadTable)> headData;
if (NS_SUCCEEDED(mFontEntry->GetFontTable(kHeadTableTag, headData)) &&
headData.Length() >= sizeof(HeadTable)) {
HeadTable *head = reinterpret_cast<HeadTable*>(headData.Elements());
upem = head->unitsPerEm;
} else {
upem = ::CGFontGetUnitsPerEm(mCGFont);
}
if (upem < 16 || upem > 16384) {
// See http://www.microsoft.com/typography/otspec/head.htm
#ifdef DEBUG
char warnBuf[1024];
sprintf(warnBuf, "Bad font metrics for: %s (invalid unitsPerEm value)",
NS_ConvertUTF16toUTF8(mFontEntry->Name()).get());
NS_WARNING(warnBuf);
#endif
return;
}
mAdjustedSize = PR_MAX(mStyle.size, 1.0f);
mFUnitsConvFactor = mAdjustedSize / upem;
// For CFF fonts, when scaling values read from CGFont* APIs, we need to
// use CG's idea of unitsPerEm, which may differ from the "true" value in
// the head table of the font (see bug 580863)
gfxFloat cgConvFactor;
if (static_cast<MacOSFontEntry*>(mFontEntry.get())->IsCFF()) {
cgConvFactor = mAdjustedSize / ::CGFontGetUnitsPerEm(mCGFont);
} else {
cgConvFactor = mFUnitsConvFactor;
}
// Try to read 'sfnt' metrics; for local, non-sfnt fonts ONLY, fall back to
// platform APIs. The InitMetrics...() functions will set mIsValid on success.
if (!InitMetricsFromSfntTables(mMetrics) &&
(!mFontEntry->IsUserFont() || mFontEntry->IsLocalUserFont())) {
InitMetricsFromATSMetrics();
}
if (!mIsValid) {
return;
}
if (mMetrics.xHeight == 0.0) {
mMetrics.xHeight = ::CGFontGetXHeight(mCGFont) * cgConvFactor;
}
if (mStyle.sizeAdjust != 0.0 && mStyle.size > 0.0 &&
mMetrics.xHeight > 0.0) {
// apply font-size-adjust, and recalculate metrics
gfxFloat aspect = mMetrics.xHeight / mStyle.size;
mAdjustedSize = mStyle.GetAdjustedSize(aspect);
mFUnitsConvFactor = mAdjustedSize / upem;
if (static_cast<MacOSFontEntry*>(mFontEntry.get())->IsCFF()) {
cgConvFactor = mAdjustedSize / ::CGFontGetUnitsPerEm(mCGFont);
} else {
cgConvFactor = mFUnitsConvFactor;
}
mMetrics.xHeight = 0.0;
if (!InitMetricsFromSfntTables(mMetrics) &&
(!mFontEntry->IsUserFont() || mFontEntry->IsLocalUserFont())) {
InitMetricsFromATSMetrics();
}
if (!mIsValid) {
// this shouldn't happen, as we succeeded earlier before applying
// the size-adjust factor! But check anyway, for paranoia's sake.
return;
}
if (mMetrics.xHeight == 0.0) {
mMetrics.xHeight = ::CGFontGetXHeight(mCGFont) * cgConvFactor;
}
}
// Once we reach here, we've got basic metrics and set mIsValid = TRUE;
// there should be no further points of actual failure in InitMetrics().
// (If one is introduced, be sure to reset mIsValid to FALSE!)
mMetrics.emHeight = mAdjustedSize;
// Measure/calculate additional metrics, independent of whether we used
// the tables directly or ATS metrics APIs
CFDataRef cmap =
::CGFontCopyTableForTag(mCGFont, TRUETYPE_TAG('c','m','a','p'));
PRUint32 glyphID;
if (mMetrics.aveCharWidth <= 0) {
mMetrics.aveCharWidth = GetCharWidth(cmap, 'x', &glyphID,
cgConvFactor);
if (glyphID == 0) {
// we didn't find 'x', so use maxAdvance rather than zero
mMetrics.aveCharWidth = mMetrics.maxAdvance;
}
}
mMetrics.aveCharWidth += mSyntheticBoldOffset;
mMetrics.maxAdvance += mSyntheticBoldOffset;
mMetrics.spaceWidth = GetCharWidth(cmap, ' ', &glyphID, cgConvFactor);
if (glyphID == 0) {
// no space glyph?!
mMetrics.spaceWidth = mMetrics.aveCharWidth;
}
mSpaceGlyph = glyphID;
mMetrics.zeroOrAveCharWidth = GetCharWidth(cmap, '0', &glyphID,
cgConvFactor);
if (glyphID == 0) {
mMetrics.zeroOrAveCharWidth = mMetrics.aveCharWidth;
}
if (cmap) {
::CFRelease(cmap);
}
CalculateDerivedMetrics(mMetrics);
SanitizeMetrics(&mMetrics, mFontEntry->mIsBadUnderlineFont);
#if 0
fprintf (stderr, "Font: %p (%s) size: %f\n", this,
NS_ConvertUTF16toUTF8(GetName()).get(), mStyle.size);
// fprintf (stderr, " fbounds.origin.x %f y %f size.width %f height %f\n", fbounds.origin.x, fbounds.origin.y, fbounds.size.width, fbounds.size.height);
fprintf (stderr, " emHeight: %f emAscent: %f emDescent: %f\n", mMetrics.emHeight, mMetrics.emAscent, mMetrics.emDescent);
fprintf (stderr, " maxAscent: %f maxDescent: %f maxAdvance: %f\n", mMetrics.maxAscent, mMetrics.maxDescent, mMetrics.maxAdvance);
fprintf (stderr, " internalLeading: %f externalLeading: %f\n", mMetrics.internalLeading, mMetrics.externalLeading);
fprintf (stderr, " spaceWidth: %f aveCharWidth: %f xHeight: %f\n", mMetrics.spaceWidth, mMetrics.aveCharWidth, mMetrics.xHeight);
fprintf (stderr, " uOff: %f uSize: %f stOff: %f stSize: %f supOff: %f subOff: %f\n", mMetrics.underlineOffset, mMetrics.underlineSize, mMetrics.strikeoutOffset, mMetrics.strikeoutSize, mMetrics.superscriptOffset, mMetrics.subscriptOffset);
#endif
}
gfxFloat
gfxMacFont::GetCharWidth(CFDataRef aCmap, PRUnichar aUniChar,
PRUint32 *aGlyphID, gfxFloat aConvFactor)
{
CGGlyph glyph = 0;
if (aCmap) {
glyph = gfxFontUtils::MapCharToGlyph(::CFDataGetBytePtr(aCmap),
::CFDataGetLength(aCmap),
aUniChar);
}
if (aGlyphID) {
*aGlyphID = glyph;
}
if (glyph) {
int advance;
if (::CGFontGetGlyphAdvances(mCGFont, &glyph, 1, &advance)) {
return advance * aConvFactor;
}
}
return 0;
}
/*static*/ void
gfxMacFont::DestroyBlobFunc(void* aUserData)
{
::CFRelease((CFDataRef)aUserData);
}
hb_blob_t *
gfxMacFont::GetFontTable(PRUint32 aTag)
{
CFDataRef dataRef = ::CGFontCopyTableForTag(mCGFont, aTag);
if (dataRef) {
return hb_blob_create((const char*)::CFDataGetBytePtr(dataRef),
::CFDataGetLength(dataRef),
HB_MEMORY_MODE_READONLY,
DestroyBlobFunc, (void*)dataRef);
}
if (mFontEntry->IsUserFont() && !mFontEntry->IsLocalUserFont()) {
// for downloaded fonts, there may be layout tables cached in the entry
// even though they're absent from the sanitized platform font
hb_blob_t *blob;
if (mFontEntry->GetExistingFontTable(aTag, &blob)) {
return blob;
}
}
return nsnull;
}
// Try to initialize font metrics via ATS font metrics APIs,
// and set mIsValid = TRUE on success.
// We ONLY call this for local (platform) fonts that are not sfnt format;
// for sfnts, including ALL downloadable fonts, use InitMetricsFromSfntTables
// because ATSFontGetHorizontalMetrics() has been known to crash when
// presented with bad fonts.
void
gfxMacFont::InitMetricsFromATSMetrics()
{
ATSFontMetrics atsMetrics;
OSStatus err;
err = ::ATSFontGetHorizontalMetrics(mATSFont, kATSOptionFlagsDefault,
&atsMetrics);
if (err != noErr) {
#ifdef DEBUG
char warnBuf[1024];
sprintf(warnBuf, "Bad font metrics for: %s err: %8.8x",
NS_ConvertUTF16toUTF8(mFontEntry->Name()).get(), PRUint32(err));
NS_WARNING(warnBuf);
#endif
return;
}
mMetrics.underlineOffset = atsMetrics.underlinePosition * mAdjustedSize;
mMetrics.underlineSize = atsMetrics.underlineThickness * mAdjustedSize;
mMetrics.externalLeading = atsMetrics.leading * mAdjustedSize;
mMetrics.maxAscent = atsMetrics.ascent * mAdjustedSize;
mMetrics.maxDescent = -atsMetrics.descent * mAdjustedSize;
mMetrics.maxAdvance = atsMetrics.maxAdvanceWidth * mAdjustedSize;
mMetrics.aveCharWidth = atsMetrics.avgAdvanceWidth * mAdjustedSize;
mMetrics.xHeight = atsMetrics.xHeight * mAdjustedSize;
mIsValid = PR_TRUE;
}