| Flutter Impeller |

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
5 #include "impeller/entity/contents/contents.h"
6 #include <optional>
7
8 #include "fml/logging.h"
9 #include "impeller/base/strings.h"
10 #include "impeller/base/validation.h"
11 #include "impeller/core/formats.h"
12 #include "impeller/entity/contents/anonymous_contents.h"
13 #include "impeller/entity/contents/content_context.h"
14 #include "impeller/entity/contents/texture_contents.h"
15 #include "impeller/renderer/command_buffer.h"
16 #include "impeller/renderer/render_pass.h"
17
18 namespace impeller {
19
20 ContentContextOptions OptionsFromPass(const RenderPass& pass) {
21 ContentContextOptions opts;
22 opts.sample_count = pass.GetSampleCount();
23 opts.color_attachment_pixel_format = pass.GetRenderTargetPixelFormat();
24
25 bool has_depth_stencil_attachments =
26 pass.HasDepthAttachment() && pass.HasStencilAttachment();
27 FML_DCHECK(pass.HasDepthAttachment() == pass.HasStencilAttachment());
28
29 opts.has_depth_stencil_attachments = has_depth_stencil_attachments;
30 if constexpr (ContentContext::kEnableStencilThenCover) {
31 opts.depth_compare = CompareFunction::kGreater;
32 opts.stencil_mode = ContentContextOptions::StencilMode::kIgnore;
33 }
34 return opts;
35 }
36
37 ContentContextOptions OptionsFromPassAndEntity(const RenderPass& pass,
38 const Entity& entity) {
39 ContentContextOptions opts = OptionsFromPass(pass);
40 opts.blend_mode = entity.GetBlendMode();
41 return opts;
42 }
43
44 std::shared_ptr<Contents> Contents::MakeAnonymous(
45 Contents::RenderProc render_proc,
46 Contents::CoverageProc coverage_proc) {
47 return AnonymousContents::Make(std::move(render_proc),
48 std::move(coverage_proc));
49 }
50
51 Contents::Contents() = default;
52
53 Contents::~Contents() = default;
54
55 bool Contents::IsOpaque() const {
56 return false;
57 }
58
59 Contents::ClipCoverage Contents::GetClipCoverage(
60 const Entity& entity,
61 const std::optional<Rect>& current_clip_coverage) const {
62 return {.type = ClipCoverage::Type::kNoChange,
63 .coverage = current_clip_coverage};
64 }
65
66 std::optional<Snapshot> Contents::RenderToSnapshot(
67 const ContentContext& renderer,
68 const Entity& entity,
69 std::optional<Rect> coverage_limit,
70 const std::optional<SamplerDescriptor>& sampler_descriptor,
71 bool msaa_enabled,
72 int32_t mip_count,
73 const std::string& label) const {
74 auto coverage = GetCoverage(entity);
75 if (!coverage.has_value()) {
76 return std::nullopt;
77 }
78
79 // Pad Contents snapshots with 1 pixel borders to ensure correct sampling
80 // behavior. Not doing so results in a coverage leak for filters that support
81 // customizing the input sampling mode. Snapshots of contents should be
82 // theoretically treated as infinite size just like layers.
83 coverage = coverage->Expand(1);
84
85 if (coverage_limit.has_value()) {
86 coverage = coverage->Intersection(*coverage_limit);
87 if (!coverage.has_value()) {
88 return std::nullopt;
89 }
90 }
91
92 ISize subpass_size = ISize::Ceil(coverage->GetSize());
93 fml::StatusOr<RenderTarget> render_target = renderer.MakeSubpass(
94 label, subpass_size,
95 [&contents = *this, &entity, &coverage](const ContentContext& renderer,
96 RenderPass& pass) -> bool {
97 Entity sub_entity;
98 sub_entity.SetBlendMode(BlendMode::kSourceOver);
99 sub_entity.SetTransform(
100 Matrix::MakeTranslation(Vector3(-coverage->GetOrigin())) *
101 entity.GetTransform());
102 return contents.Render(renderer, sub_entity, pass);
103 },
104 msaa_enabled, /*depth_stencil_enabled=*/true,
105 std::min(mip_count, static_cast<int32_t>(subpass_size.MipCount())));
106
107 if (!render_target.ok()) {
108 return std::nullopt;
109 }
110
111 auto snapshot = Snapshot{
112 .texture = render_target.value().GetRenderTargetTexture(),
113 .transform = Matrix::MakeTranslation(coverage->GetOrigin()),
114 };
115 if (sampler_descriptor.has_value()) {
116 snapshot.sampler_descriptor = sampler_descriptor.value();
117 }
118
119 return snapshot;
120 }
121
122 bool Contents::CanInheritOpacity(const Entity& entity) const {
123 return false;
124 }
125
126 void Contents::SetInheritedOpacity(Scalar opacity) {
127 VALIDATION_LOG << "Contents::SetInheritedOpacity should never be called when "
128 "Contents::CanAcceptOpacity returns false.";
129 }
130
131 std::optional<Color> Contents::AsBackgroundColor(const Entity& entity,
132 ISize target_size) const {
133 return {};
134 }
135
136 const FilterContents* Contents::AsFilter() const {
137 return nullptr;
138 }
139
140 bool Contents::ApplyColorFilter(
141 const Contents::ColorFilterProc& color_filter_proc) {
142 return false;
143 }
144
145 bool Contents::ShouldRender(const Entity& entity,
146 const std::optional<Rect> clip_coverage) const {
147 if (!clip_coverage.has_value()) {
148 return false;
149 }
150 auto coverage = GetCoverage(entity);
151 if (!coverage.has_value()) {
152 return false;
153 }
154 if (coverage == Rect::MakeMaximum()) {
155 return true;
156 }
157 return clip_coverage->IntersectsWithRect(coverage.value());
158 }
159
160 void Contents::SetCoverageHint(std::optional<Rect> coverage_hint) {
161 coverage_hint_ = coverage_hint;
162 }
163
164 const std::optional<Rect>& Contents::GetCoverageHint() const {
165 return coverage_hint_;
166 }
167
168 std::optional<Size> Contents::GetColorSourceSize() const {
169 return color_source_size_;
170 };
171
172 void Contents::SetColorSourceSize(Size size) {
173 color_source_size_ = size;
174 }
175
176 } // namespace impeller
impeller::ContentContextOptions::StencilMode::kIgnore
@ kIgnore
Turn the stencil test off. Used when drawing without stencil-then-cover.
impeller::Contents::GetColorSourceSize
std::optional< Size > GetColorSourceSize() const
Return the color source's intrinsic size, if available.
Definition: contents.cc:168
impeller::OptionsFromPass
ContentContextOptions OptionsFromPass(const RenderPass &pass)
Definition: contents.cc:20
impeller::CompareFunction::kGreater
@ kGreater
Comparison test passes if new_value > current_value.
contents.h
impeller::Scalar
float Scalar
Definition: scalar.h:18
impeller::Entity::SetBlendMode
void SetBlendMode(BlendMode blend_mode)
Definition: entity.cc:130
impeller::Contents::SetCoverageHint
void SetCoverageHint(std::optional< Rect > coverage_hint)
Hint that specifies the coverage area of this Contents that will actually be used during rendering....
Definition: contents.cc:160
impeller::Contents::AsBackgroundColor
virtual std::optional< Color > AsBackgroundColor(const Entity &entity, ISize target_size) const
Returns a color if this Contents will flood the given target_size with a color. This output color is ...
Definition: contents.cc:131
texture_contents.h
impeller::Entity::GetTransform
const Matrix & GetTransform() const
Get the global transform matrix for this Entity.
Definition: entity.cc:49
impeller::Contents::SetColorSourceSize
void SetColorSourceSize(Size size)
Definition: contents.cc:172
impeller::Contents::CanInheritOpacity
virtual bool CanInheritOpacity(const Entity &entity) const
Whether or not this contents can accept the opacity peephole optimization.
Definition: contents.cc:122
impeller::Contents::RenderToSnapshot
virtual std::optional< Snapshot > RenderToSnapshot(const ContentContext &renderer, const Entity &entity, std::optional< Rect > coverage_limit=std::nullopt, const std::optional< SamplerDescriptor > &sampler_descriptor=std::nullopt, bool msaa_enabled=true, int32_t mip_count=1, const std::string &label="Snapshot") const
Render this contents to a snapshot, respecting the entity's transform, path, clip depth,...
Definition: contents.cc:66
impeller::Contents::Contents
Contents()
formats.h
impeller::Contents::GetCoverage
virtual std::optional< Rect > GetCoverage(const Entity &entity) const =0
Get the area of the render pass that will be affected when this contents is rendered.
impeller::TSize< int64_t >::Ceil
constexpr TSize Ceil() const
Definition: size.h:96
impeller::ContentContextOptions::has_depth_stencil_attachments
bool has_depth_stencil_attachments
Definition: content_context.h:339
impeller::ContentContextOptions::blend_mode
BlendMode blend_mode
Definition: content_context.h:333
impeller::Matrix::MakeTranslation
static constexpr Matrix MakeTranslation(const Vector3 &t)
Definition: matrix.h:95
validation.h
impeller::Contents::GetClipCoverage
virtual ClipCoverage GetClipCoverage(const Entity &entity, const std::optional< Rect > &current_clip_coverage) const
Given the current pass space bounding rectangle of the clip buffer, return the expected clip coverage...
Definition: contents.cc:59
impeller::ContentContext::kEnableStencilThenCover
static constexpr bool kEnableStencilThenCover
Definition: content_context.h:411
impeller::Entity
Definition: entity.h:21
impeller::OptionsFromPassAndEntity
ContentContextOptions OptionsFromPassAndEntity(const RenderPass &pass, const Entity &entity)
Definition: contents.cc:37
impeller::Contents::GetCoverageHint
const std::optional< Rect > & GetCoverageHint() const
Definition: contents.cc:164
impeller::TSize< int64_t >
impeller::ContentContextOptions::color_attachment_pixel_format
PixelFormat color_attachment_pixel_format
Definition: content_context.h:338
render_pass.h
impeller::Contents::~Contents
virtual ~Contents()
impeller::ContentContext::MakeSubpass
fml::StatusOr< RenderTarget > MakeSubpass(const std::string &label, ISize texture_size, const SubpassCallback &subpass_callback, bool msaa_enabled=true, bool depth_stencil_enabled=false, int32_t mip_count=1) const
Creates a new texture of size texture_size and calls subpass_callback with a RenderPass for drawing t...
Definition: content_context.cc:478
impeller::Contents::ColorFilterProc
std::function< Color(Color)> ColorFilterProc
Definition: contents.h:38
impeller::Contents::ClipCoverage::type
Type type
Definition: contents.h:43
impeller::Snapshot
Represents a texture and its intended draw transform/sampler configuration.
Definition: snapshot.h:25
impeller::RenderPass::GetSampleCount
SampleCount GetSampleCount() const
The sample count of the attached render target.
Definition: render_pass.cc:23
impeller::Contents::ShouldRender
virtual bool ShouldRender(const Entity &entity, const std::optional< Rect > clip_coverage) const
Definition: contents.cc:145
impeller::ContentContextOptions::stencil_mode
StencilMode stencil_mode
Definition: content_context.h:335
strings.h
impeller::RenderPass::HasDepthAttachment
bool HasDepthAttachment() const
Whether the render target has a depth attachment.
Definition: render_pass.cc:31
anonymous_contents.h
impeller::Entity::GetBlendMode
BlendMode GetBlendMode() const
Definition: entity.cc:134
impeller::RenderPass
Render passes encode render commands directed as one specific render target into an underlying comman...
Definition: render_pass.h:33
VALIDATION_LOG
#define VALIDATION_LOG
Definition: validation.h:73
command_buffer.h
content_context.h
impeller::ContentContextOptions::depth_compare
CompareFunction depth_compare
Definition: content_context.h:334
impeller::Entity::SetTransform
void SetTransform(const Matrix &transform)
Set the global transform matrix for this Entity.
Definition: entity.cc:65
impeller::Contents::RenderProc
std::function< bool(const ContentContext &renderer, const Entity &entity, RenderPass &pass)> RenderProc
Definition: contents.h:49
impeller::ContentContextOptions::sample_count
SampleCount sample_count
Definition: content_context.h:332
impeller::TRect< Scalar >::MakeMaximum
constexpr static TRect MakeMaximum()
Definition: rect.h:174
impeller::Contents::SetInheritedOpacity
virtual void SetInheritedOpacity(Scalar opacity)
Inherit the provided opacity.
Definition: contents.cc:126
impeller::RenderPass::HasStencilAttachment
bool HasStencilAttachment() const
Whether the render target has an stencil attachment.
Definition: render_pass.cc:35
impeller::Contents::ClipCoverage
Definition: contents.h:40
impeller::Contents::MakeAnonymous
static std::shared_ptr< Contents > MakeAnonymous(RenderProc render_proc, CoverageProc coverage_proc)
Definition: contents.cc:44
impeller::Contents::ApplyColorFilter
virtual bool ApplyColorFilter(const ColorFilterProc &color_filter_proc)
If possible, applies a color filter to this contents inputs on the CPU.
Definition: contents.cc:140
impeller::Contents::CoverageProc
std::function< std::optional< Rect >(const Entity &entity)> CoverageProc
Definition: contents.h:50
impeller::Snapshot::texture
std::shared_ptr< Texture > texture
Definition: snapshot.h:26
impeller::TSize::MipCount
constexpr size_t MipCount() const
Definition: size.h:115
impeller::Contents::IsOpaque
virtual bool IsOpaque() const
Whether this Contents only emits opaque source colors from the fragment stage. This value does not ac...
Definition: contents.cc:55
impeller::ContentContextOptions
Definition: content_context.h:288
impeller
Definition: aiks_blur_unittests.cc:20
impeller::ContentContext
Definition: content_context.h:392
impeller::Contents::AsFilter
virtual const FilterContents * AsFilter() const
Cast to a filter. Returns nullptr if this Contents is not a filter.
Definition: contents.cc:136
impeller::Contents::ClipCoverage::Type::kNoChange
@ kNoChange
impeller::Vector3
Definition: vector.h:20
impeller::BlendMode::kSourceOver
@ kSourceOver
impeller::AnonymousContents::Make
static std::shared_ptr< Contents > Make(RenderProc render_proc, CoverageProc coverage_proc)
Definition: anonymous_contents.cc:11
impeller::FilterContents
Definition: filter_contents.h:22
impeller::RenderPass::GetRenderTargetPixelFormat
PixelFormat GetRenderTargetPixelFormat() const
The pixel format of the attached render target.
Definition: render_pass.cc:27