gfx/thebes/COLRFonts.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 COLR_FONTS_H
   7 #define COLR_FONTS_H
   8
   9 #include "mozilla/gfx/2D.h"
  10 #include "mozilla/UniquePtr.h"
  11 #include "nsAtom.h"
  12 #include "nsTArray.h"
  13 #include "nsTHashtable.h"
  14
  15 struct hb_blob_t;
  16 struct hb_face_t;
  17 struct hb_font_t;
  18
  19 namespace mozilla {
  20
  21 namespace layout {
  22 class TextDrawTarget;
  23 }
  24
  25 namespace gfx {
  26
  27 class FontPaletteValueSet {
  28  public:
  29   NS_INLINE_DECL_THREADSAFE_REFCOUNTING(FontPaletteValueSet)
  30
  31   struct OverrideColor {
  32     uint32_t mIndex = 0;
  33     sRGBColor mColor;
  34   };
  35
  36   struct PaletteValues {
  37     enum { kLight = -1, kDark = -2 };
  38     int32_t mBasePalette = 0;  // 0-based index, or kLight/kDark constants
  39     nsTArray<OverrideColor> mOverrides;
  40   };
  41
  42   const PaletteValues* Lookup(nsAtom* aName, const nsACString& aFamily) const;
  43
  44   PaletteValues* Insert(nsAtom* aName, const nsACString& aFamily);
  45
  46  private:
  47   ~FontPaletteValueSet() = default;
  48
  49   struct PaletteHashKey {
  50     RefPtr<nsAtom> mName;
  51     nsCString mFamily;
  52
  53     PaletteHashKey() = delete;
  54     PaletteHashKey(nsAtom* aName, const nsACString& aFamily)
  55         : mName(aName), mFamily(aFamily) {}
  56     PaletteHashKey(const PaletteHashKey& aKey) = default;
  57   };
  58
  59   class HashEntry : public PLDHashEntryHdr {
  60    public:
  61     using KeyType = const PaletteHashKey&;
  62     using KeyTypePointer = const PaletteHashKey*;
  63
  64     HashEntry() = delete;
  65     explicit HashEntry(KeyTypePointer aKey) : mKey(*aKey) {}
  66     HashEntry(HashEntry&& other) noexcept
  67         : PLDHashEntryHdr(std::move(other)),
  68           mKey(other.mKey),
  69           mValue(std::move(other.mValue)) {
  70       NS_ERROR("Should not be called");
  71     }
  72     ~HashEntry() = default;
  73
  74     bool KeyEquals(const KeyTypePointer aKey) const {
  75       return mKey.mName == aKey->mName && mKey.mFamily.Equals(aKey->mFamily);
  76     }
  77     static KeyTypePointer KeyToPointer(KeyType aKey) { return &aKey; }
  78     static PLDHashNumber HashKey(const KeyTypePointer aKey) {
  79       return aKey->mName->hash() +
  80              HashString(aKey->mFamily.get(), aKey->mFamily.Length());
  81     }
  82     enum { ALLOW_MEMMOVE = true };
  83
  84     PaletteHashKey mKey;
  85     PaletteValues mValue;
  86   };
  87
  88   nsTHashtable<HashEntry> mValues;
  89 };
  90
  91 class COLRFonts {
  92  public:
  93   static bool ValidateColorGlyphs(hb_blob_t* aCOLR, hb_blob_t* aCPAL);
  94
  95   // COLRv0: color glyph is represented as a simple list of colored layers.
  96   // (This is used only as an opaque pointer; the internal type is private.)
  97   struct GlyphLayers;
  98
  99   static const GlyphLayers* GetGlyphLayers(hb_blob_t* aCOLR, uint32_t aGlyphId);
 100
 101   static bool PaintGlyphLayers(
 102       hb_blob_t* aCOLR, hb_face_t* aFace, const GlyphLayers* aLayers,
 103       DrawTarget* aDrawTarget, layout::TextDrawTarget* aTextDrawer,
 104       ScaledFont* aScaledFont, DrawOptions aDrawOptions, const Point& aPoint,
 105       const sRGBColor& aCurrentColor, const nsTArray<sRGBColor>* aColors);
 106
 107   // COLRv1 support: color glyph is represented by a directed acyclic graph of
 108   // paint records.
 109   // (This is used only as an opaque pointer; the internal type is private.)
 110   struct GlyphPaintGraph;
 111
 112   static const GlyphPaintGraph* GetGlyphPaintGraph(hb_blob_t* aCOLR,
 113                                                    uint32_t aGlyphId);
 114
 115   static bool PaintGlyphGraph(
 116       hb_blob_t* aCOLR, hb_font_t* aFont, const GlyphPaintGraph* aPaintGraph,
 117       DrawTarget* aDrawTarget, layout::TextDrawTarget* aTextDrawer,
 118       ScaledFont* aScaledFont, DrawOptions aDrawOptions, const Point& aPoint,
 119       const sRGBColor& aCurrentColor, const nsTArray<sRGBColor>* aColors,
 120       uint32_t aGlyphId, float aFontUnitsToPixels);
 121
 122   static Rect GetColorGlyphBounds(hb_blob_t* aCOLR, hb_font_t* aFont,
 123                                   uint32_t aGlyphId, DrawTarget* aDrawTarget,
 124                                   ScaledFont* aScaledFont,
 125                                   float aFontUnitsToPixels);
 126
 127   static uint16_t GetColrTableVersion(hb_blob_t* aCOLR);
 128
 129   static UniquePtr<nsTArray<sRGBColor>> SetupColorPalette(
 130       hb_face_t* aFace, const FontPaletteValueSet* aPaletteValueSet,
 131       nsAtom* aFontPalette, const nsACString& aFamilyName);
 132 };
 133
 134 }  // namespace gfx
 135
 136 }  // namespace mozilla
 137
 138 #endif  // COLR_FONTS_H