Flutter Impeller
sweep_gradient_contents.cc
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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 
6 
7 #include "flutter/fml/logging.h"
11 #include "impeller/entity/entity.h"
14 
15 namespace impeller {
16 
18 
20 
22  Degrees start_angle,
23  Degrees end_angle) {
24  center_ = center;
25  Scalar t0 = start_angle.degrees / 360;
26  Scalar t1 = end_angle.degrees / 360;
27  FML_DCHECK(t0 < t1);
28  bias_ = -t0;
29  scale_ = 1 / (t1 - t0);
30 }
31 
32 void SweepGradientContents::SetColors(std::vector<Color> colors) {
33  colors_ = std::move(colors);
34 }
35 
36 void SweepGradientContents::SetStops(std::vector<Scalar> stops) {
37  stops_ = std::move(stops);
38 }
39 
41  tile_mode_ = tile_mode;
42 }
43 
44 const std::vector<Color>& SweepGradientContents::GetColors() const {
45  return colors_;
46 }
47 
48 const std::vector<Scalar>& SweepGradientContents::GetStops() const {
49  return stops_;
50 }
51 
53  if (GetOpacityFactor() < 1 || tile_mode_ == Entity::TileMode::kDecal) {
54  return false;
55  }
56  for (auto color : colors_) {
57  if (!color.IsOpaque()) {
58  return false;
59  }
60  }
61  return true;
62 }
63 
65  const Entity& entity,
66  RenderPass& pass) const {
67  if (renderer.GetDeviceCapabilities().SupportsSSBO()) {
68  return RenderSSBO(renderer, entity, pass);
69  }
70  return RenderTexture(renderer, entity, pass);
71 }
72 
73 bool SweepGradientContents::RenderSSBO(const ContentContext& renderer,
74  const Entity& entity,
75  RenderPass& pass) const {
78 
79  VS::FrameInfo frame_info;
80  frame_info.matrix = GetInverseEffectTransform();
81  VS::BindFrameInfo(pass,
82  renderer.GetTransientsBuffer().EmplaceUniform(frame_info));
83 
84  PipelineBuilderCallback pipeline_callback =
85  [&renderer](ContentContextOptions options) {
86  return renderer.GetSweepGradientSSBOFillPipeline(options);
87  };
88  return ColorSourceContents::DrawGeometry<VS>(
89  renderer, entity, pass, pipeline_callback, frame_info,
90  [this, &renderer](RenderPass& pass) {
91  FS::FragInfo frag_info;
92  frag_info.center = center_;
93  frag_info.bias = bias_;
94  frag_info.scale = scale_;
95  frag_info.tile_mode = static_cast<Scalar>(tile_mode_);
96  frag_info.decal_border_color = decal_border_color_;
97  frag_info.alpha = GetOpacityFactor();
98 
99  auto& host_buffer = renderer.GetTransientsBuffer();
100  auto colors = CreateGradientColors(colors_, stops_);
101 
102  frag_info.colors_length = colors.size();
103  auto color_buffer =
104  host_buffer.Emplace(colors.data(), colors.size() * sizeof(StopData),
106 
107  pass.SetCommandLabel("SweepGradientSSBOFill");
108 
109  FS::BindFragInfo(
110  pass, renderer.GetTransientsBuffer().EmplaceUniform(frag_info));
111  FS::BindColorData(pass, color_buffer);
112 
113  return true;
114  });
115 }
116 
117 bool SweepGradientContents::RenderTexture(const ContentContext& renderer,
118  const Entity& entity,
119  RenderPass& pass) const {
122 
123  auto gradient_data = CreateGradientBuffer(colors_, stops_);
124  auto gradient_texture =
125  CreateGradientTexture(gradient_data, renderer.GetContext());
126  if (gradient_texture == nullptr) {
127  return false;
128  }
129 
130  VS::FrameInfo frame_info;
131  frame_info.matrix = GetInverseEffectTransform();
132 
133  PipelineBuilderCallback pipeline_callback =
134  [&renderer](ContentContextOptions options) {
135  return renderer.GetSweepGradientFillPipeline(options);
136  };
137  return ColorSourceContents::DrawGeometry<VS>(
138  renderer, entity, pass, pipeline_callback, frame_info,
139  [this, &renderer, &gradient_texture](RenderPass& pass) {
140  FS::FragInfo frag_info;
141  frag_info.center = center_;
142  frag_info.bias = bias_;
143  frag_info.scale = scale_;
144  frag_info.texture_sampler_y_coord_scale =
145  gradient_texture->GetYCoordScale();
146  frag_info.tile_mode = static_cast<Scalar>(tile_mode_);
147  frag_info.decal_border_color = decal_border_color_;
148  frag_info.alpha = GetOpacityFactor();
149  frag_info.half_texel =
150  Vector2(0.5 / gradient_texture->GetSize().width,
151  0.5 / gradient_texture->GetSize().height);
152 
153  SamplerDescriptor sampler_desc;
154  sampler_desc.min_filter = MinMagFilter::kLinear;
155  sampler_desc.mag_filter = MinMagFilter::kLinear;
156 
157  pass.SetCommandLabel("SweepGradientFill");
158 
159  FS::BindFragInfo(
160  pass, renderer.GetTransientsBuffer().EmplaceUniform(frag_info));
161  FS::BindTextureSampler(
162  pass, gradient_texture,
163  renderer.GetContext()->GetSamplerLibrary()->GetSampler(
164  sampler_desc));
165 
166  return true;
167  });
168 }
169 
171  const ColorFilterProc& color_filter_proc) {
172  for (Color& color : colors_) {
173  color = color_filter_proc(color);
174  }
175  decal_border_color_ = color_filter_proc(decal_border_color_);
176  return true;
177 }
178 
179 } // namespace impeller
impeller::SweepGradientContents::ApplyColorFilter
bool ApplyColorFilter(const ColorFilterProc &color_filter_proc) override
If possible, applies a color filter to this contents inputs on the CPU.
Definition: sweep_gradient_contents.cc:170
impeller::ColorSourceContents::PipelineBuilderCallback
std::function< std::shared_ptr< Pipeline< PipelineDescriptor > >(ContentContextOptions)> PipelineBuilderCallback
Definition: color_source_contents.h:113
impeller::ColorSourceContents::GetOpacityFactor
Scalar GetOpacityFactor() const
Get the opacity factor for this color source.
Definition: color_source_contents.cc:28
impeller::SweepGradientContents::SetTileMode
void SetTileMode(Entity::TileMode tile_mode)
Definition: sweep_gradient_contents.cc:40
gradient_generator.h
impeller::Scalar
float Scalar
Definition: scalar.h:18
impeller::DefaultUniformAlignment
constexpr size_t DefaultUniformAlignment()
Definition: platform.h:15
impeller::Degrees::degrees
Scalar degrees
Definition: scalar.h:47
entity.h
impeller::SweepGradientContents::SetColors
void SetColors(std::vector< Color > colors)
Definition: sweep_gradient_contents.cc:32
impeller::SweepGradientContents::SetCenterAndAngles
void SetCenterAndAngles(Point center, Degrees start_angle, Degrees end_angle)
Definition: sweep_gradient_contents.cc:21
impeller::Color
Definition: color.h:124
impeller::Entity::TileMode::kDecal
@ kDecal
impeller::Vector2
Point Vector2
Definition: point.h:320
impeller::SweepGradientContents::~SweepGradientContents
~SweepGradientContents() override
impeller::SweepGradientContents::GetStops
const std::vector< Scalar > & GetStops() const
Definition: sweep_gradient_contents.cc:48
impeller::RenderPipelineT::FragmentShader
FragmentShader_ FragmentShader
Definition: pipeline.h:94
impeller::Color::alpha
Scalar alpha
Definition: color.h:143
impeller::ContentContext::GetSweepGradientSSBOFillPipeline
std::shared_ptr< Pipeline< PipelineDescriptor > > GetSweepGradientSSBOFillPipeline(ContentContextOptions opts) const
Definition: content_context.h:450
sweep_gradient_contents.h
gradient.h
impeller::VS
SolidFillVertexShader VS
Definition: stroke_path_geometry.cc:15
impeller::Entity
Definition: entity.h:21
render_pass.h
impeller::SweepGradientContents::SetStops
void SetStops(std::vector< Scalar > stops)
Definition: sweep_gradient_contents.cc:36
impeller::Contents::ColorFilterProc
std::function< Color(Color)> ColorFilterProc
Definition: contents.h:38
impeller::MinMagFilter::kLinear
@ kLinear
clip_contents.h
impeller::CreateGradientBuffer
GradientData CreateGradientBuffer(const std::vector< Color > &colors, const std::vector< Scalar > &stops)
Populate a vector with the interpolated color bytes for the linear gradient described by colors and s...
Definition: gradient.cc:20
impeller::SweepGradientContents::SweepGradientContents
SweepGradientContents()
impeller::Entity::TileMode
TileMode
Definition: entity.h:42
impeller::SweepGradientContents::IsOpaque
bool IsOpaque() const override
Whether this Contents only emits opaque source colors from the fragment stage. This value does not ac...
Definition: sweep_gradient_contents.cc:52
impeller::RenderPass
Render passes encode render commands directed as one specific render target into an underlying comman...
Definition: render_pass.h:33
content_context.h
impeller::SweepGradientContents::Render
bool Render(const ContentContext &renderer, const Entity &entity, RenderPass &pass) const override
Definition: sweep_gradient_contents.cc:64
impeller::ContentContext::GetDeviceCapabilities
const Capabilities & GetDeviceCapabilities() const
Definition: content_context.cc:568
impeller::TPoint< Scalar >
impeller::HostBuffer::EmplaceUniform
BufferView EmplaceUniform(const UniformType &uniform)
Emplace uniform data onto the host buffer. Ensure that backend specific uniform alignment requirement...
Definition: host_buffer.h:50
impeller::Degrees
Definition: scalar.h:46
impeller::CreateGradientColors
std::vector< StopData > CreateGradientColors(const std::vector< Color > &colors, const std::vector< Scalar > &stops)
Populate a vector with the color and stop data for a gradient.
Definition: gradient_generator.cc:45
impeller::CreateGradientTexture
std::shared_ptr< Texture > CreateGradientTexture(const GradientData &gradient_data, const std::shared_ptr< impeller::Context > &context)
Create a host visible texture that contains the gradient defined by the provided gradient data.
Definition: gradient_generator.cc:17
impeller::SweepGradientContents::GetColors
const std::vector< Color > & GetColors() const
Definition: sweep_gradient_contents.cc:44
impeller::RenderPipelineT::VertexShader
VertexShader_ VertexShader
Definition: pipeline.h:93
impeller::ContentContextOptions
Definition: content_context.h:288
impeller::Capabilities::SupportsSSBO
virtual bool SupportsSSBO() const =0
Whether the context backend supports binding Shader Storage Buffer Objects (SSBOs) to pipelines.
impeller
Definition: aiks_blur_unittests.cc:20
impeller::ContentContext
Definition: content_context.h:392
impeller::ColorSourceContents::GetInverseEffectTransform
const Matrix & GetInverseEffectTransform() const
Set the inverted effect transform for this color source.
Definition: color_source_contents.cc:36
impeller::ContentContext::GetTransientsBuffer
HostBuffer & GetTransientsBuffer() const
Retrieve the currnent host buffer for transient storage.
Definition: content_context.h:833