src/third_party/WebKit/Source/platform/fonts/linux/FontPlatformDataLinux.cpp

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  30
  31 #include "config.h"
  32 #include "public/platform/Platform.h"
  33
  34 #include "SkTypeface.h"
  35 #include "platform/LayoutTestSupport.h"
  36 #include "platform/RuntimeEnabledFeatures.h"
  37 #include "platform/fonts/harfbuzz/FontPlatformDataHarfBuzz.h"
  38 #include "platform/graphics/GraphicsContext.h"
  39 #include "public/platform/linux/WebFontRenderStyle.h"
  40 #include "public/platform/linux/WebSandboxSupport.h"
  41
  42 namespace blink {
  43
  44 static SkPaint::Hinting skiaHinting = SkPaint::kNormal_Hinting;
  45 static bool useSkiaAutoHint = true;
  46 static bool useSkiaBitmaps = true;
  47 static bool useSkiaAntiAlias = true;
  48 static bool useSkiaSubpixelRendering = false;
  49
  50 void FontPlatformData::setHinting(SkPaint::Hinting hinting)
  51 {
  52     skiaHinting = hinting;
  53 }
  54
  55 void FontPlatformData::setAutoHint(bool useAutoHint)
  56 {
  57     useSkiaAutoHint = useAutoHint;
  58 }
  59
  60 void FontPlatformData::setUseBitmaps(bool useBitmaps)
  61 {
  62     useSkiaBitmaps = useBitmaps;
  63 }
  64
  65 void FontPlatformData::setAntiAlias(bool useAntiAlias)
  66 {
  67     useSkiaAntiAlias = useAntiAlias;
  68 }
  69
  70 void FontPlatformData::setSubpixelRendering(bool useSubpixelRendering)
  71 {
  72     useSkiaSubpixelRendering = useSubpixelRendering;
  73 }
  74
  75 void FontPlatformData::setupPaint(SkPaint* paint, GraphicsContext* context)
  76     const
  77 {
  78     paint->setAntiAlias(m_style.useAntiAlias);
  79     paint->setHinting(static_cast<SkPaint::Hinting>(m_style.hintStyle));
  80     paint->setEmbeddedBitmapText(m_style.useBitmaps);
  81     paint->setAutohinted(m_style.useAutoHint);
  82     if (m_style.useAntiAlias)
  83         paint->setLCDRenderText(m_style.useSubpixelRendering);
  84
  85     // Do not enable subpixel text on low-dpi if full hinting is requested.
  86     bool useSubpixelText = RuntimeEnabledFeatures::subpixelFontScalingEnabled()
  87         && (paint->getHinting() != SkPaint::kFull_Hinting
  88             || (context && context->deviceScaleFactor() > 1.0f));
  89
  90     // TestRunner specifically toggles the subpixel positioning flag.
  91     if (useSubpixelText && !LayoutTestSupport::isRunningLayoutTest())
  92         paint->setSubpixelText(true);
  93     else
  94         paint->setSubpixelText(m_style.useSubpixelPositioning);
  95
  96     const float ts = m_textSize >= 0 ? m_textSize : 12;
  97     paint->setTextSize(SkFloatToScalar(ts));
  98     paint->setTypeface(m_typeface.get());
  99     paint->setFakeBoldText(m_syntheticBold);
 100     paint->setTextSkewX(m_syntheticItalic ? -SK_Scalar1 / 4 : 0);
 101 }
 102
 103 void FontPlatformData::querySystemForRenderStyle(bool useSkiaSubpixelPositioning)
 104 {
 105     WebFontRenderStyle style;
 106 #if OS(ANDROID)
 107     style.setDefaults();
 108 #else
 109     // If the font name is missing (i.e. probably a web font) or the sandbox is disabled, use the system defaults.
 110     if (!m_family.length() || !Platform::current()->sandboxSupport()) {
 111         style.setDefaults();
 112     } else {
 113         const int sizeAndStyle = (((int)m_textSize) << 2) | (m_typeface->style() & 3);
 114         Platform::current()->sandboxSupport()->getRenderStyleForStrike(m_family.data(), sizeAndStyle, &style);
 115     }
 116 #endif
 117     style.toFontRenderStyle(&m_style);
 118
 119     // Fix FontRenderStyle::NoPreference to actual styles.
 120     if (m_style.useAntiAlias == FontRenderStyle::NoPreference)
 121         m_style.useAntiAlias = useSkiaAntiAlias;
 122
 123     if (!m_style.useHinting)
 124         m_style.hintStyle = SkPaint::kNo_Hinting;
 125     else if (m_style.useHinting == FontRenderStyle::NoPreference)
 126         m_style.hintStyle = skiaHinting;
 127
 128     if (m_style.useBitmaps == FontRenderStyle::NoPreference)
 129         m_style.useBitmaps = useSkiaBitmaps;
 130     if (m_style.useAutoHint == FontRenderStyle::NoPreference)
 131         m_style.useAutoHint = useSkiaAutoHint;
 132     if (m_style.useAntiAlias == FontRenderStyle::NoPreference)
 133         m_style.useAntiAlias = useSkiaAntiAlias;
 134     if (m_style.useSubpixelRendering == FontRenderStyle::NoPreference)
 135         m_style.useSubpixelRendering = useSkiaSubpixelRendering;
 136
 137     // TestRunner specifically toggles the subpixel positioning flag.
 138     if (m_style.useSubpixelPositioning == FontRenderStyle::NoPreference
 139         || LayoutTestSupport::isRunningLayoutTest())
 140         m_style.useSubpixelPositioning = useSkiaSubpixelPositioning;
 141 }
 142
 143 bool FontPlatformData::defaultUseSubpixelPositioning()
 144 {
 145     return FontDescription::subpixelPositioning();
 146 }
 147
 148 } // namespace blink