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/*
* Copyright (C) 2006, 2007 Apple Computer, Inc.
* Copyright (c) 2006, 2007, 2008, 2009, 2012 Google Inc. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are
* met:
*
* * Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* * Redistributions in binary form must reproduce the above
* copyright notice, this list of conditions and the following disclaimer
* in the documentation and/or other materials provided with the
* distribution.
* * Neither the name of Google Inc. nor the names of its
* contributors may be used to endorse or promote products derived from
* this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
* OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#include "config.h"
#include "platform/fonts/FontPlatformData.h"
#include "SkTypeface.h"
#include "platform/LayoutTestSupport.h"
#include "platform/fonts/FontCache.h"
#include "platform/graphics/GraphicsContext.h"
#include <windows.h>
namespace WebCore {
// Maximum font size, in pixels, at which embedded bitmaps will be used
// if available.
const float kMaxSizeForEmbeddedBitmap = 24.0f;
void FontPlatformData::setupPaint(SkPaint* paint, GraphicsContext* context) const
{
const float ts = m_textSize >= 0 ? m_textSize : 12;
paint->setTextSize(SkFloatToScalar(m_textSize));
paint->setTypeface(typeface());
paint->setFakeBoldText(m_syntheticBold);
paint->setTextSkewX(m_syntheticItalic ? -SK_Scalar1 / 4 : 0);
uint32_t textFlags = paintTextFlags();
uint32_t flags = paint->getFlags();
static const uint32_t textFlagsMask = SkPaint::kAntiAlias_Flag |
SkPaint::kLCDRenderText_Flag |
SkPaint::kGenA8FromLCD_Flag;
flags &= ~textFlagsMask;
if (ts <= kMaxSizeForEmbeddedBitmap)
flags |= SkPaint::kEmbeddedBitmapText_Flag;
if (ts >= m_minSizeForAntiAlias) {
if (m_useSubpixelPositioning)
flags |= SkPaint::kSubpixelText_Flag;
// Only set painting flags when we're actually painting.
if (context && !context->couldUseLCDRenderedText()) {
textFlags &= ~SkPaint::kLCDRenderText_Flag;
// If we *just* clear our request for LCD, then GDI seems to
// sometimes give us AA text, and sometimes give us BW text. Since the
// original intent was LCD, we want to force AA (rather than BW), so we
// add a special bit to tell Skia to do its best to avoid the BW: by
// drawing LCD offscreen and downsampling that to AA.
textFlags |= SkPaint::kGenA8FromLCD_Flag;
}
SkASSERT(!(textFlags & ~textFlagsMask));
flags |= textFlags;
}
paint->setFlags(flags);
}
// Lookup the current system settings for font smoothing.
// We cache these values for performance, but if the browser has a way to be
// notified when these change, we could re-query them at that time.
static uint32_t getSystemTextFlags()
{
static bool gInited;
static uint32_t gFlags;
if (!gInited) {
BOOL enabled;
gFlags = 0;
if (SystemParametersInfo(SPI_GETFONTSMOOTHING, 0, &enabled, 0)) {
if (enabled) {
gFlags |= SkPaint::kAntiAlias_Flag;
UINT smoothType;
if (SystemParametersInfo(SPI_GETFONTSMOOTHINGTYPE, 0, &smoothType, 0)) {
if (FE_FONTSMOOTHINGCLEARTYPE == smoothType)
gFlags |= SkPaint::kLCDRenderText_Flag;
}
}
} else {
// SystemParametersInfo will fail only under full sandbox lockdown on Win8+.
// So, we default to settings we know are supported and look good.
// FIXME(eae): We should be querying the DirectWrite settings directly
// so we can respect the settings for users who turn off smoothing.
gFlags = SkPaint::kAntiAlias_Flag | SkPaint::kLCDRenderText_Flag;
}
gInited = true;
}
return gFlags;
}
static bool isWebFont(const String& familyName)
{
// Web-fonts have artifical names constructed to always be:
// 1. 24 characters, followed by a '\0'
// 2. the last two characters are '=='
return familyName.length() == 24
&& '=' == familyName[22] && '=' == familyName[23];
}
static int computePaintTextFlags(String fontFamilyName)
{
if (isRunningLayoutTest())
return isFontAntialiasingEnabledForTest() ? SkPaint::kAntiAlias_Flag : 0;
int textFlags = getSystemTextFlags();
// Many web-fonts are so poorly hinted that they are terrible to read when drawn in BW.
// In these cases, we have decided to FORCE these fonts to be drawn with at least grayscale AA,
// even when the System (getSystemTextFlags) tells us to draw only in BW.
if (isWebFont(fontFamilyName))
textFlags |= SkPaint::kAntiAlias_Flag;
return textFlags;
}
void FontPlatformData::querySystemForRenderStyle(bool)
{
m_paintTextFlags = computePaintTextFlags(fontFamilyName());
}
bool FontPlatformData::defaultUseSubpixelPositioning()
{
return FontCache::fontCache()->useSubpixelPositioning();
}
} // namespace WebCore
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