/*
* Copyright (C) 1999 Lars Knoll (knoll@kde.org)
* (C) 1999 Antti Koivisto (koivisto@kde.org)
* (C) 2000 Dirk Mueller (mueller@kde.org)
* Copyright (C) 2003, 2006, 2007, 2008, 2009, 2010 Apple Inc.
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Library General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Library General Public License for more details.
*
* You should have received a copy of the GNU Library General Public License
* along with this library; see the file COPYING.LIB. If not, write to
* the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
* Boston, MA 02110-1301, USA.
*/
#import "config.h"
#import "Font.h"
#import "GlyphBuffer.h"
#import "GraphicsContext.h"
#import "Logging.h"
#import "SimpleFontData.h"
#import "WebCoreSystemInterface.h"
#import "BitmapImage.h"
#import "SharedBuffer.h"
#import "WAKView.h"
#import "WKGraphics.h"
#import <CoreText/CoreText.h>
#import <GraphicsServices/GraphicsServices.h>
#import <wtf/StdLibExtras.h>
#import <wtf/Threading.h>
#define SYNTHETIC_OBLIQUE_ANGLE 14
#ifdef __LP64__
#define URefCon void*
#else
#define URefCon UInt32
#endif
using namespace std;
namespace WebCore {
bool Font::canReturnFallbackFontsForComplexText()
{
return true;
}
bool Font::canExpandAroundIdeographsInComplexText()
{
return true;
}
// CTFontGetVerticalTranslationsForGlyphs is different on Snow Leopard. It returns values for a font-size of 1
// without unitsPerEm applied. We have to apply a transform that scales up to the point size and that also
// divides by unitsPerEm.
static bool hasBrokenCTFontGetVerticalTranslationsForGlyphs()
{
return false;
}
static void showGlyphsWithAdvances(const FloatPoint& point, const SimpleFontData* font, CGContextRef context, const CGGlyph* glyphs, const CGSize* advances, size_t count)
{
CGContextSetTextPosition(context, point.x(), point.y());
const FontPlatformData& platformData = font->platformData();
if (!platformData.isColorBitmapFont()) {
CGAffineTransform savedMatrix;
bool isVertical = font->platformData().orientation() == Vertical;
if (isVertical) {
CGAffineTransform rotateLeftTransform = CGAffineTransformMake(0, -1, 1, 0, 0, 0);
savedMatrix = CGContextGetTextMatrix(context);
CGAffineTransform runMatrix = CGAffineTransformConcat(savedMatrix, rotateLeftTransform);
CGContextSetTextMatrix(context, runMatrix);
CGAffineTransform translationsTransform;
if (hasBrokenCTFontGetVerticalTranslationsForGlyphs()) {
translationsTransform = CGAffineTransformMake(platformData.m_size, 0, 0, platformData.m_size, 0, 0);
translationsTransform = CGAffineTransformConcat(translationsTransform, rotateLeftTransform);
CGFloat unitsPerEm = CGFontGetUnitsPerEm(platformData.cgFont());
translationsTransform = CGAffineTransformConcat(translationsTransform, CGAffineTransformMakeScale(1 / unitsPerEm, 1 / unitsPerEm));
} else {
translationsTransform = rotateLeftTransform;
}
Vector<CGSize, 256> translations(count);
CTFontGetVerticalTranslationsForGlyphs(platformData.ctFont(), glyphs, translations.data(), count);
CGAffineTransform transform = CGAffineTransformInvert(CGContextGetTextMatrix(context));
CGPoint position = FloatPoint(point.x(), point.y() + font->fontMetrics().floatAscent(IdeographicBaseline) - font->fontMetrics().floatAscent());
Vector<CGPoint, 256> positions(count);
for (size_t i = 0; i < count; ++i) {
CGSize translation = CGSizeApplyAffineTransform(translations[i], translationsTransform);
positions[i] = CGPointApplyAffineTransform(CGPointMake(position.x - translation.width, position.y + translation.height), transform);
position.x += advances[i].width;
position.y += advances[i].height;
}
CGContextShowGlyphsAtPositions(context, glyphs, positions.data(), count);
CGContextSetTextMatrix(context, savedMatrix);
} else
CGContextShowGlyphsWithAdvances(context, glyphs, advances, count);
}
else {
if (!count)
return;
Vector<CGPoint, 256> positions(count);
CGAffineTransform matrix = CGAffineTransformInvert(CGContextGetTextMatrix(context));
positions[0] = CGPointZero;
for (size_t i = 1; i < count; ++i) {
CGSize advance = CGSizeApplyAffineTransform(advances[i - 1], matrix);
positions[i].x = positions[i - 1].x + advance.width;
positions[i].y = positions[i - 1].y + advance.height;
}
CTFontDrawGlyphs(platformData.ctFont(), glyphs, positions.data(), count, context);
}
}
void Font::drawGlyphs(GraphicsContext* context, const SimpleFontData* font, const GlyphBuffer& glyphBuffer, int from, int numGlyphs, const FloatPoint& anchorPoint, bool /*setColor*/) const
{
CGContextRef cgContext = context->platformContext();
bool shouldSmoothFonts = true;
bool changeFontSmoothing = false;
switch(fontDescription().fontSmoothing()) {
case Antialiased: {
context->setShouldAntialias(true);
shouldSmoothFonts = false;
changeFontSmoothing = true;
break;
}
case SubpixelAntialiased: {
context->setShouldAntialias(true);
shouldSmoothFonts = true;
changeFontSmoothing = true;
break;
}
case NoSmoothing: {
context->setShouldAntialias(false);
shouldSmoothFonts = false;
changeFontSmoothing = true;
break;
}
case AutoSmoothing: {
// For the AutoSmooth case, don't do anything! Keep the default settings.
break;
}
default:
ASSERT_NOT_REACHED();
}
if (!shouldUseSmoothing()) {
shouldSmoothFonts = false;
changeFontSmoothing = true;
}
const FontPlatformData& platformData = font->platformData();
CGContextSetFont(cgContext, platformData.cgFont());
FloatPoint point = anchorPoint;
float fontSize = platformData.size();
if (platformData.m_isEmoji) {
if (!context->emojiDrawingEnabled())
return;
// Mimic the positioining of non-bitmap glyphs, which are not subpixel-positioned.
point.setY(ceilf(point.y()));
// Emoji glyphs snap to the CSS pixel grid.
point.setX(floorf(point.x()));
// Emoji glyphs are offset one CSS pixel to the right.
point.move(1, 0);
// Emoji glyphs are offset vertically based on font size.
float y = point.y();
if (fontSize <= 15) {
// Undo Core Text's y adjustment.
point.setY(floorf(y) - .1f * (fontSize + 2) + 2);
} else {
if (fontSize < 26)
y -= .35f * fontSize - 10;
// Undo Core Text's y adjustment.
point.setY(floorf(y) - 2);
}
}
CGAffineTransform matrix = platformData.isColorBitmapFont() ? CGAffineTransformIdentity : CGAffineTransformMakeScale(fontSize, fontSize);
matrix.b = -matrix.b;
matrix.d = -matrix.d;
if (platformData.m_syntheticOblique)
matrix = CGAffineTransformConcat(matrix, CGAffineTransformMake(1, 0, -tanf(SYNTHETIC_OBLIQUE_ANGLE * acosf(0) / 90), 1, 0, 0));
CGContextSetTextMatrix(cgContext, matrix);
CGContextSetFontSize(cgContext, 1.0f);
FloatSize shadowOffset;
float shadowBlur;
Color shadowColor;
ColorSpace shadowColorSpace;
ColorSpace fillColorSpace = context->fillColorSpace();
context->getShadow(shadowOffset, shadowBlur, shadowColor, shadowColorSpace);
bool hasSimpleShadow = context->textDrawingMode() == TextModeFill && shadowColor.isValid() && !shadowBlur && !platformData.isColorBitmapFont() && (!context->shadowsIgnoreTransforms() || context->getCTM().isIdentityOrTranslationOrFlipped());
if (hasSimpleShadow) {
// Paint simple shadows ourselves instead of relying on CG shadows, to avoid losing subpixel antialiasing.
context->clearShadow();
Color fillColor = context->fillColor();
Color shadowFillColor(shadowColor.red(), shadowColor.green(), shadowColor.blue(), shadowColor.alpha() * fillColor.alpha() / 255);
context->setFillColor(shadowFillColor, shadowColorSpace);
float shadowTextX = point.x() + shadowOffset.width();
// If shadows are ignoring transforms, then we haven't applied the Y coordinate flip yet, so down is negative.
float shadowTextY = point.y() + shadowOffset.height() * (context->shadowsIgnoreTransforms() ? -1 : 1);
showGlyphsWithAdvances(FloatPoint(shadowTextX, shadowTextY), font, cgContext, glyphBuffer.glyphs(from), glyphBuffer.advances(from), numGlyphs);
if (font->syntheticBoldOffset() && !platformData.m_isEmoji)
showGlyphsWithAdvances(FloatPoint(shadowTextX + font->syntheticBoldOffset(), shadowTextY), font, cgContext, glyphBuffer.glyphs(from), glyphBuffer.advances(from), numGlyphs);
context->setFillColor(fillColor, fillColorSpace);
}
showGlyphsWithAdvances(point, font, cgContext, glyphBuffer.glyphs(from), glyphBuffer.advances(from), numGlyphs);
if (font->syntheticBoldOffset() && !platformData.m_isEmoji)
showGlyphsWithAdvances(FloatPoint(point.x() + font->syntheticBoldOffset(), point.y()), font, cgContext, glyphBuffer.glyphs(from), glyphBuffer.advances(from), numGlyphs);
if (hasSimpleShadow)
context->setShadow(shadowOffset, shadowBlur, shadowColor, shadowColorSpace);
}
}