| Flutter Impeller |

color_source_contents.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 #pragma once
6
7 #include "flutter/fml/macros.h"
8 #include "impeller/entity/contents/contents.h"
9 #include "impeller/entity/geometry/geometry.h"
10 #include "impeller/geometry/matrix.h"
11 #include "impeller/geometry/path.h"
12
13 namespace impeller {
14
15 //------------------------------------------------------------------------------
16 /// Color sources are geometry-ignostic `Contents` capable of shading any area
17 /// defined by an `impeller::Geometry`. Conceptually,
18 /// `impeller::ColorSourceContents` implement a particular color shading
19 /// behavior.
20 ///
21 /// This separation of concerns between geometry and color source output allows
22 /// Impeller to handle most possible draw combinations in a consistent way.
23 /// For example: There are color sources for handling solid colors, gradients,
24 /// textures, custom runtime effects, and even 3D scenes.
25 ///
26 /// There are some special rendering exceptions that deviate from this pattern
27 /// and cross geometry and color source concerns, such as text atlas and image
28 /// atlas rendering. Special `Contents` exist for rendering these behaviors
29 /// which don't implement `ColorSourceContents`.
30 ///
31 /// @see `impeller::Geometry`
32 ///
33 class ColorSourceContents : public Contents {
34 public:
35 ColorSourceContents();
36
37 ~ColorSourceContents() override;
38
39 //----------------------------------------------------------------------------
40 /// @brief Set the geometry that this contents will use to render.
41 ///
42 void SetGeometry(std::shared_ptr<Geometry> geometry);
43
44 //----------------------------------------------------------------------------
45 /// @brief Get the geometry that this contents will use to render.
46 ///
47 const std::shared_ptr<Geometry>& GetGeometry() const;
48
49 //----------------------------------------------------------------------------
50 /// @brief Set the effect transform for this color source.
51 ///
52 /// The effect transform is a transformation matrix that is applied to
53 /// the shaded color output and does not impact geometry in any way.
54 ///
55 /// For example: With repeat tiling, any gradient or
56 /// `TiledTextureContents` could be used with an effect transform to
57 /// inexpensively draw an infinite scrolling background pattern.
58 ///
59 void SetEffectTransform(Matrix matrix);
60
61 //----------------------------------------------------------------------------
62 /// @brief Set the inverted effect transform for this color source.
63 ///
64 /// When the effect transform is set via `SetEffectTransform`, the
65 /// value is inverted upon storage. The reason for this is that most
66 /// color sources internally use the inverted transform.
67 ///
68 /// @return The inverse of the transform set by `SetEffectTransform`.
69 ///
70 /// @see `SetEffectTransform`
71 ///
72 const Matrix& GetInverseEffectTransform() const;
73
74 //----------------------------------------------------------------------------
75 /// @brief Set the opacity factor for this color source.
76 ///
77 void SetOpacityFactor(Scalar opacity);
78
79 //----------------------------------------------------------------------------
80 /// @brief Get the opacity factor for this color source.
81 ///
82 /// This value is is factored into the output of the color source in
83 /// addition to opacity information that may be supplied any other
84 /// inputs.
85 ///
86 /// @note If set, the output of this method factors factors in the inherited
87 /// opacity of this `Contents`.
88 ///
89 /// @see `Contents::CanInheritOpacity`
90 ///
91 Scalar GetOpacityFactor() const;
92
93 virtual bool IsSolidColor() const;
94
95 // |Contents|
96 std::optional<Rect> GetCoverage(const Entity& entity) const override;
97
98 // |Contents|
99 bool CanInheritOpacity(const Entity& entity) const override;
100
101 // |Contents|
102 void SetInheritedOpacity(Scalar opacity) override;
103
104 private:
105 std::shared_ptr<Geometry> geometry_;
106 Matrix inverse_matrix_;
107 Scalar opacity_ = 1.0;
108 Scalar inherited_opacity_ = 1.0;
109
110 FML_DISALLOW_COPY_AND_ASSIGN(ColorSourceContents);
111 };
112
113 } // namespace impeller
path.h
impeller::ColorSourceContents::GetOpacityFactor
Scalar GetOpacityFactor() const
Get the opacity factor for this color source.
Definition: color_source_contents.cc:29
contents.h
impeller::ColorSourceContents::IsSolidColor
virtual bool IsSolidColor() const
Definition: color_source_contents.cc:41
impeller::ColorSourceContents::SetInheritedOpacity
void SetInheritedOpacity(Scalar opacity) override
Inherit the provided opacity.
Definition: color_source_contents.cc:54
impeller::Scalar
float Scalar
Definition: scalar.h:15
impeller::ColorSourceContents::SetGeometry
void SetGeometry(std::shared_ptr< Geometry > geometry)
Set the geometry that this contents will use to render.
Definition: color_source_contents.cc:17
impeller::ColorSourceContents::SetEffectTransform
void SetEffectTransform(Matrix matrix)
Set the effect transform for this color source.
Definition: color_source_contents.cc:33
impeller::ColorSourceContents::GetGeometry
const std::shared_ptr< Geometry > & GetGeometry() const
Get the geometry that this contents will use to render.
Definition: color_source_contents.cc:21
impeller::ColorSourceContents::CanInheritOpacity
bool CanInheritOpacity(const Entity &entity) const override
Whether or not this contents can accept the opacity peephole optimization.
Definition: color_source_contents.cc:50
impeller::ColorSourceContents::ColorSourceContents
ColorSourceContents()
matrix.h
impeller::Entity
Definition: entity.h:21
impeller::ColorSourceContents::~ColorSourceContents
~ColorSourceContents() override
geometry.h
impeller::ColorSourceContents::GetCoverage
std::optional< Rect > GetCoverage(const Entity &entity) const override
Get the screen space bounding rectangle that this contents affects.
Definition: color_source_contents.cc:45
impeller::ColorSourceContents::SetOpacityFactor
void SetOpacityFactor(Scalar opacity)
Set the opacity factor for this color source.
Definition: color_source_contents.cc:25
impeller::Contents
Definition: contents.h:33
impeller::ColorSourceContents
Definition: color_source_contents.h:33
impeller
Definition: aiks_context.cc:10
impeller::Matrix
A 4x4 matrix using column-major storage.
Definition: matrix.h:36
impeller::ColorSourceContents::GetInverseEffectTransform
const Matrix & GetInverseEffectTransform() const
Set the inverted effect transform for this color source.
Definition: color_source_contents.cc:37