gfx/thebes/gfxDWriteFonts.h

   1 /* -*- Mode: C++; tab-width: 20; indent-tabs-mode: nil; c-basic-offset: 2 -*-
   2  * This Source Code Form is subject to the terms of the Mozilla Public
   3  * License, v. 2.0. If a copy of the MPL was not distributed with this
   4  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
   5
   6 #ifndef GFX_WINDOWSDWRITEFONTS_H
   7 #define GFX_WINDOWSDWRITEFONTS_H
   8
   9 #include "mozilla/Atomics.h"
  10 #include "mozilla/MemoryReporting.h"
  11 #include "mozilla/UniquePtr.h"
  12 #include <dwrite_1.h>
  13
  14 #include "gfxFont.h"
  15 #include "gfxUserFontSet.h"
  16 #include "nsTHashMap.h"
  17 #include "nsHashKeys.h"
  18
  19 #include "mozilla/gfx/gfxVars.h"
  20 #include "mozilla/gfx/UnscaledFontDWrite.h"
  21
  22 /**
  23  * \brief Class representing a font face for a font entry.
  24  */
  25 class gfxDWriteFont final : public gfxFont {
  26  public:
  27   gfxDWriteFont(const RefPtr<mozilla::gfx::UnscaledFontDWrite>& aUnscaledFont,
  28                 gfxFontEntry* aFontEntry, const gfxFontStyle* aFontStyle,
  29                 RefPtr<IDWriteFontFace> aFontFace = nullptr,
  30                 AntialiasOption = kAntialiasDefault);
  31
  32   static bool InitDWriteSupport();
  33
  34   // These Update functions update gfxVars with font settings, they must only be
  35   // called in the parent process.
  36   static void UpdateSystemTextVars();
  37   static void UpdateClearTypeVars();
  38
  39   static void SystemTextQualityChanged();
  40
  41   gfxFont* CopyWithAntialiasOption(AntialiasOption anAAOption) const override;
  42
  43   bool AllowSubpixelAA() const override { return mAllowManualShowGlyphs; }
  44
  45   bool IsValid() const;
  46
  47   IDWriteFontFace* GetFontFace();
  48
  49   /* override Measure to add padding for antialiasing */
  50   RunMetrics Measure(const gfxTextRun* aTextRun, uint32_t aStart, uint32_t aEnd,
  51                      BoundingBoxType aBoundingBoxType,
  52                      DrawTarget* aDrawTargetForTightBoundingBox,
  53                      Spacing* aSpacing,
  54                      mozilla::gfx::ShapedTextFlags aOrientation) override;
  55
  56   bool ProvidesGlyphWidths() const override;
  57
  58   int32_t GetGlyphWidth(uint16_t aGID) override;
  59
  60   bool GetGlyphBounds(uint16_t aGID, gfxRect* aBounds, bool aTight) override;
  61
  62   void AddSizeOfExcludingThis(mozilla::MallocSizeOf aMallocSizeOf,
  63                               FontCacheSizes* aSizes) const override;
  64   void AddSizeOfIncludingThis(mozilla::MallocSizeOf aMallocSizeOf,
  65                               FontCacheSizes* aSizes) const override;
  66
  67   FontType GetType() const override { return FONT_TYPE_DWRITE; }
  68
  69   already_AddRefed<mozilla::gfx::ScaledFont> GetScaledFont(
  70       const TextRunDrawParams& aRunParams) override;
  71
  72   bool ShouldRoundXOffset(cairo_t* aCairo) const override;
  73
  74  protected:
  75   ~gfxDWriteFont() override;
  76
  77   const Metrics& GetHorizontalMetrics() const override { return mMetrics; }
  78
  79   bool GetFakeMetricsForArialBlack(DWRITE_FONT_METRICS* aFontMetrics);
  80
  81   void ComputeMetrics(AntialiasOption anAAOption);
  82
  83   bool HasBitmapStrikeForSize(uint32_t aSize);
  84
  85   gfxFloat MeasureGlyphWidth(uint16_t aGlyph);
  86
  87   DWRITE_MEASURING_MODE GetMeasuringMode() const;
  88
  89   static mozilla::Atomic<bool> sForceGDIClassicEnabled;
  90   bool GetForceGDIClassic() const;
  91
  92   RefPtr<IDWriteFontFace> mFontFace;
  93   RefPtr<IDWriteFontFace1> mFontFace1;  // may be unavailable on older DWrite
  94
  95   Metrics mMetrics;
  96
  97   // cache of glyph widths in 16.16 fixed-point pixels
  98   mozilla::UniquePtr<nsTHashMap<nsUint32HashKey, int32_t>> mGlyphWidths;
  99
 100   bool mUseSubpixelPositions;
 101   bool mAllowManualShowGlyphs;
 102
 103   // Used to record the sUseClearType setting at the time mAzureScaledFont
 104   // was set up, so we can tell if it's stale and needs to be re-created.
 105   mozilla::Atomic<bool> mAzureScaledFontUsedClearType;
 106
 107   // Cache the GDI version of the ScaledFont so that font keys and other
 108   // meta-data can remain stable even if there is thrashing between GDI and
 109   // non-GDI usage.
 110   mozilla::Atomic<mozilla::gfx::ScaledFont*> mAzureScaledFontGDI;
 111
 112   bool UsingClearType() {
 113     return mozilla::gfx::gfxVars::SystemTextQuality() == CLEARTYPE_QUALITY;
 114   }
 115 };
 116
 117 #endif