| Flutter Impeller |

text_frame.h
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1 // Copyright 2013 The Flutter Authors. All rights reserved.
2 // Use of this source code is governed by a BSD-style license that can be
3 // found in the LICENSE file.
4
5 #ifndef FLUTTER_IMPELLER_TYPOGRAPHER_TEXT_FRAME_H_
6 #define FLUTTER_IMPELLER_TYPOGRAPHER_TEXT_FRAME_H_
7
8 #include "impeller/typographer/glyph_atlas.h"
9 #include "impeller/typographer/text_run.h"
10
11 namespace impeller {
12
13 //------------------------------------------------------------------------------
14 /// @brief Represents a collection of shaped text runs.
15 ///
16 /// This object is typically the entrypoint in the Impeller type
17 /// rendering subsystem.
18 ///
19 class TextFrame {
20 public:
21 TextFrame();
22
23 TextFrame(std::vector<TextRun>& runs, Rect bounds, bool has_color);
24
25 ~TextFrame();
26
27 void CollectUniqueFontGlyphPairs(FontGlyphMap& glyph_map,
28 Scalar scale,
29 Point offset,
30 const GlyphProperties& properties) const;
31
32 static Point ComputeSubpixelPosition(
33 const TextRun::GlyphPosition& glyph_position,
34 AxisAlignment alignment,
35 Point offset,
36 Scalar scale);
37
38 static Scalar RoundScaledFontSize(Scalar scale, Scalar point_size);
39
40 //----------------------------------------------------------------------------
41 /// @brief The conservative bounding box for this text frame.
42 ///
43 /// @return The bounds rectangle. If there are no glyphs in this text
44 /// frame and empty Rectangle is returned instead.
45 ///
46 Rect GetBounds() const;
47
48 //----------------------------------------------------------------------------
49 /// @brief The number of runs in this text frame.
50 ///
51 /// @return The run count.
52 ///
53 size_t GetRunCount() const;
54
55 //----------------------------------------------------------------------------
56 /// @brief Returns a reference to all the text runs in this frame.
57 ///
58 /// @return The runs in this frame.
59 ///
60 const std::vector<TextRun>& GetRuns() const;
61
62 //----------------------------------------------------------------------------
63 /// @brief Returns the paint color this text frame was recorded with.
64 ///
65 /// Non-bitmap/COLR fonts always use a black text color here, but
66 /// COLR fonts can potentially use the paint color in the glyph
67 /// atlas, so this color must be considered as part of the cache
68 /// key.
69 bool HasColor() const;
70
71 //----------------------------------------------------------------------------
72 /// @brief The type of atlas this run should be emplaced in.
73 GlyphAtlas::Type GetAtlasType() const;
74
75 TextFrame& operator=(TextFrame&& other) = default;
76
77 TextFrame(const TextFrame& other) = default;
78
79 private:
80 std::vector<TextRun> runs_;
81 Rect bounds_;
82 bool has_color_;
83 };
84
85 } // namespace impeller
86
87 #endif // FLUTTER_IMPELLER_TYPOGRAPHER_TEXT_FRAME_H_
impeller::TextFrame::operator=
TextFrame & operator=(TextFrame &&other)=default
impeller::TextFrame::HasColor
bool HasColor() const
Returns the paint color this text frame was recorded with.
Definition: text_frame.cc:35
impeller::Scalar
float Scalar
Definition: scalar.h:18
impeller::FontGlyphMap
std::unordered_map< ScaledFont, std::unordered_set< SubpixelGlyph, SubpixelGlyph::Hash, SubpixelGlyph::Equal >, ScaledFont::Hash, ScaledFont::Equal > FontGlyphMap
Definition: font_glyph_pair.h:108
impeller::GlyphProperties
Definition: font_glyph_pair.h:20
impeller::TextFrame::TextFrame
TextFrame()
impeller::TextFrame
Represents a collection of shaped text runs.
Definition: text_frame.h:19
impeller::TextFrame::~TextFrame
~TextFrame()
impeller::TextFrame::ComputeSubpixelPosition
static Point ComputeSubpixelPosition(const TextRun::GlyphPosition &glyph_position, AxisAlignment alignment, Point offset, Scalar scale)
Definition: text_frame.cc:68
impeller::TextFrame::GetRuns
const std::vector< TextRun > & GetRuns() const
Returns a reference to all the text runs in this frame.
Definition: text_frame.cc:26
impeller::TextFrame::GetRunCount
size_t GetRunCount() const
The number of runs in this text frame.
Definition: text_frame.cc:22
impeller::TextFrame::RoundScaledFontSize
static Scalar RoundScaledFontSize(Scalar scale, Scalar point_size)
Definition: text_frame.cc:40
offset
SeparatedVector2 offset
Definition: stroke_path_geometry.cc:304
impeller::GlyphAtlas::Type
Type
Describes how the glyphs are represented in the texture.
Definition: glyph_atlas.h:31
impeller::AxisAlignment
AxisAlignment
Determines the axis along which there is subpixel positioning.
Definition: font.h:20
impeller::TextFrame::CollectUniqueFontGlyphPairs
void CollectUniqueFontGlyphPairs(FontGlyphMap &glyph_map, Scalar scale, Point offset, const GlyphProperties &properties) const
Definition: text_frame.cc:87
impeller::TextFrame::GetBounds
Rect GetBounds() const
The conservative bounding box for this text frame.
Definition: text_frame.cc:18
text_run.h
impeller::TextFrame::GetAtlasType
GlyphAtlas::Type GetAtlasType() const
The type of atlas this run should be emplaced in.
Definition: text_frame.cc:30
impeller::TPoint< Scalar >
impeller::TextRun::GlyphPosition
Definition: text_run.h:22
scale
const Scalar scale
Definition: stroke_path_geometry.cc:301
glyph_atlas.h
impeller
Definition: allocation.cc:12
impeller::TRect< Scalar >