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/FontPlatformData.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, const Font*) const
  76 {
  77     paint->setAntiAlias(m_style.useAntiAlias);
  78     paint->setHinting(static_cast<SkPaint::Hinting>(m_style.hintStyle));
  79     paint->setEmbeddedBitmapText(m_style.useBitmaps);
  80     paint->setAutohinted(m_style.useAutoHint);
  81     if (m_style.useAntiAlias)
  82         paint->setLCDRenderText(m_style.useSubpixelRendering);
  83
  84     // Do not enable subpixel text on low-dpi if full hinting is requested.
  85     bool useSubpixelText = RuntimeEnabledFeatures::subpixelFontScalingEnabled()
  86         && (paint->getHinting() != SkPaint::kFull_Hinting
  87             || (context && context->deviceScaleFactor() > 1.0f));
  88
  89     // TestRunner specifically toggles the subpixel positioning flag.
  90     if (useSubpixelText && !LayoutTestSupport::isRunningLayoutTest())
  91         paint->setSubpixelText(true);
  92     else
  93         paint->setSubpixelText(m_style.useSubpixelPositioning);
  94
  95     const float ts = m_textSize >= 0 ? m_textSize : 12;
  96     paint->setTextSize(SkFloatToScalar(ts));
  97     paint->setTypeface(m_typeface.get());
  98     paint->setFakeBoldText(m_syntheticBold);
  99     paint->setTextSkewX(m_syntheticItalic ? -SK_Scalar1 / 4 : 0);
 100 }
 101
 102 void FontPlatformData::querySystemForRenderStyle(bool useSkiaSubpixelPositioning)
 103 {
 104     WebFontRenderStyle style;
 105 #if OS(ANDROID)
 106     style.setDefaults();
 107 #else
 108     // If the font name is missing (i.e. probably a web font) or the sandbox is disabled, use the system defaults.
 109     if (!m_family.length() || !Platform::current()->sandboxSupport()) {
 110         style.setDefaults();
 111     } else {
 112         const int sizeAndStyle = (((int)m_textSize) << 2) | (m_typeface->style() & 3);
 113         Platform::current()->sandboxSupport()->getRenderStyleForStrike(m_family.data(), sizeAndStyle, &style);
 114     }
 115 #endif
 116     style.toFontRenderStyle(&m_style);
 117
 118     // Fix FontRenderStyle::NoPreference to actual styles.
 119     if (m_style.useAntiAlias == FontRenderStyle::NoPreference)
 120         m_style.useAntiAlias = useSkiaAntiAlias;
 121
 122     if (!m_style.useHinting)
 123         m_style.hintStyle = SkPaint::kNo_Hinting;
 124     else if (m_style.useHinting == FontRenderStyle::NoPreference)
 125         m_style.hintStyle = skiaHinting;
 126
 127     if (m_style.useBitmaps == FontRenderStyle::NoPreference)
 128         m_style.useBitmaps = useSkiaBitmaps;
 129     if (m_style.useAutoHint == FontRenderStyle::NoPreference)
 130         m_style.useAutoHint = useSkiaAutoHint;
 131     if (m_style.useAntiAlias == FontRenderStyle::NoPreference)
 132         m_style.useAntiAlias = useSkiaAntiAlias;
 133     if (m_style.useSubpixelRendering == FontRenderStyle::NoPreference)
 134         m_style.useSubpixelRendering = useSkiaSubpixelRendering;
 135
 136     // TestRunner specifically toggles the subpixel positioning flag.
 137     if (m_style.useSubpixelPositioning == FontRenderStyle::NoPreference
 138         || LayoutTestSupport::isRunningLayoutTest())
 139         m_style.useSubpixelPositioning = useSkiaSubpixelPositioning;
 140 }
 141
 142 bool FontPlatformData::defaultUseSubpixelPositioning()
 143 {
 144     return FontDescription::subpixelPositioning();
 145 }
 146
 147 } // namespace blink