| Flutter Impeller |

Classes | Public Member Functions | List of all members
impeller::RuntimeEffectContents Class Referencefinal

`#include <runtime_effect_contents.h>`

Inheritance diagram for impeller::RuntimeEffectContents:

## Classes
struct | TextureInput

## Public Member Functions
void | SetRuntimeStage (std::shared_ptr< RuntimeStage > runtime_stage)
void | SetUniformData (std::shared_ptr< std::vector< uint8_t >> uniform_data)
void | SetTextureInputs (std::vector< TextureInput > texture_inputs)
bool | CanInheritOpacity (const Entity &entity) const override
| Whether or not this contents can accept the opacity peephole optimization. More...
bool | Render (const ContentContext &renderer, const Entity &entity, RenderPass &pass) const override
bool | BootstrapShader (const ContentContext &renderer) const
| Load the runtime effect and ensure a default PSO is initialized. More...
Public Member Functions inherited from impeller::ColorSourceContents
| ColorSourceContents ()
| ~ColorSourceContents () override
void | SetGeometry (std::shared_ptr< Geometry > geometry)
| Set the geometry that this contents will use to render. More...
const std::shared_ptr< Geometry > & | GetGeometry () const
| Get the geometry that this contents will use to render. More...
void | SetEffectTransform (Matrix matrix)
| Set the effect transform for this color source. More...
const Matrix & | GetInverseEffectTransform () const
| Set the inverted effect transform for this color source. More...
void | SetOpacityFactor (Scalar opacity)
| Set the opacity factor for this color source. More...
Scalar | GetOpacityFactor () const
| Get the opacity factor for this color source. More...
virtual bool | IsSolidColor () const
std::optional< Rect > | GetCoverage (const Entity &entity) const override
| Get the area of the render pass that will be affected when this contents is rendered. More...
void | SetInheritedOpacity (Scalar opacity) override
| Inherit the provided opacity. More...
Public Member Functions inherited from impeller::Contents
| Contents ()
virtual | ~Contents ()
virtual void | PopulateGlyphAtlas (const std::shared_ptr< LazyGlyphAtlas > &lazy_glyph_atlas, Scalar scale)
| Add any text data to the specified lazy atlas. The scale parameter must be used again later when drawing the text. More...
void | SetCoverageHint (std::optional< Rect > coverage_hint)
| Hint that specifies the coverage area of this Contents that will actually be used during rendering. This is for optimization purposes only and can not be relied on as a clip. May optionally affect the result of `GetCoverage()`. More...
const std::optional< Rect > & | GetCoverageHint () const
virtual bool | IsOpaque () const
| Whether this Contents only emits opaque source colors from the fragment stage. This value does not account for any entity properties (e.g. the blend mode), clips/visibility culling, or inherited opacity. More...
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 after this draw call. This should only be implemented for contents that may write to the clip buffer. More...
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, and blend mode. The result texture size is always the size of `GetCoverage(entity)`. More...
virtual bool | ShouldRender (const Entity &entity, const std::optional< Rect > clip_coverage) const
std::optional< Size > | GetColorSourceSize () const
| Return the color source's intrinsic size, if available. More...
void | SetColorSourceSize (Size size)
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 the "Source" color that will be used for the Entity's blend operation. More...
virtual const FilterContents * | AsFilter () const
| Cast to a filter. Returns `nullptr` if this Contents is not a filter. More...
virtual bool | ApplyColorFilter (const ColorFilterProc &color_filter_proc)
| If possible, applies a color filter to this contents inputs on the CPU. More...

## Additional Inherited Members
Public Types inherited from impeller::Contents
using | ColorFilterProc = std::function< Color(Color)>
using | RenderProc = std::function< bool(const ContentContext &renderer, const Entity &entity, RenderPass &pass)>
using | CoverageProc = std::function< std::optional< Rect >(const Entity &entity)>
Static Public Member Functions inherited from impeller::Contents
static std::shared_ptr< Contents > | MakeAnonymous (RenderProc render_proc, CoverageProc coverage_proc)
Protected Types inherited from impeller::ColorSourceContents
using | BindFragmentCallback = std::function< bool(RenderPass &pass)>
using | PipelineBuilderMethod = std::shared_ptr< Pipeline< PipelineDescriptor > >(impeller::ContentContext::*)(ContentContextOptions) const
using | PipelineBuilderCallback = std::function< std::shared_ptr< Pipeline< PipelineDescriptor > >(ContentContextOptions)>
using | CreateGeometryCallback = std::function< GeometryResult(const ContentContext &renderer, const Entity &entity, RenderPass &pass, const Geometry &geom)>
Protected Member Functions inherited from impeller::ColorSourceContents
template<typename VertexShaderT >
bool | DrawGeometry (const ContentContext &renderer, const Entity &entity, RenderPass &pass, const PipelineBuilderCallback &pipeline_callback, typename VertexShaderT::FrameInfo frame_info, const BindFragmentCallback &bind_fragment_callback, bool force_stencil=false, const CreateGeometryCallback &create_geom_callback=DefaultCreateGeometryCallback) const
Static Protected Member Functions inherited from impeller::ColorSourceContents
static GeometryResult | DefaultCreateGeometryCallback (const ContentContext &renderer, const Entity &entity, RenderPass &pass, const Geometry &geom)

## Detailed Description

Definition at line 17 of file runtime_effect_contents.h.

## Member Function Documentation

## ◆ BootstrapShader()

bool impeller::RuntimeEffectContents::BootstrapShader | ( | const ContentContext & | renderer | ) | const

Load the runtime effect and ensure a default PSO is initialized.

Definition at line 70 of file runtime_effect_contents.cc.

71 {
72 if (!RegisterShader(renderer)) {
73 return false;
74 }
75 ContentContextOptions options;
76 options.color_attachment_pixel_format =
77 renderer.GetContext()->GetCapabilities()->GetDefaultColorFormat();
78 CreatePipeline(renderer, options, /*async=*/true);
79 return true;
80 }

References impeller::ContentContextOptions::color_attachment_pixel_format, and impeller::ContentContext::GetContext().

## ◆ CanInheritOpacity()

bool impeller::RuntimeEffectContents::CanInheritOpacity | ( | const Entity & | entity | ) | const
| override virtual

Whether or not this contents can accept the opacity peephole optimization.

By default all contents return false. Contents are responsible for determining whether or not their own geometries intersect in a way that makes accepting opacity impossible. It is always safe to return false, especially if computing overlap would be computationally expensive.

Reimplemented from impeller::ColorSourceContents.

Definition at line 42 of file runtime_effect_contents.cc.

42 {
43 return false;
44 }

## ◆ Render()

bool impeller::RuntimeEffectContents::Render | ( | const ContentContext & | renderer,
|  | const Entity & | entity,
|  | RenderPass & | pass
| ) |  | const
| override virtual

Get or register shader. Flutter will do this when the runtime effect is first loaded, but this check is added to supporting testing of the Aiks API and non-flutter usage of Impeller.

Fragment stage uniforms.

Now that the descriptor set layouts are known, get the pipeline.

Implements impeller::Contents.

Definition at line 188 of file runtime_effect_contents.cc.

190 {
191 const std::shared_ptr<Context>& context = renderer.GetContext();
192 const std::shared_ptr<ShaderLibrary>& library = context->GetShaderLibrary();
193
194 //--------------------------------------------------------------------------
195 /// Get or register shader. Flutter will do this when the runtime effect
196 /// is first loaded, but this check is added to supporting testing of the
197 /// Aiks API and non-flutter usage of Impeller.
198 ///
199 if (!RegisterShader(renderer)) {
200 return false;
201 }
202
203 //--------------------------------------------------------------------------
204 /// Fragment stage uniforms.
205 ///
206 BindFragmentCallback bind_callback = [this, &renderer,
207 &context](RenderPass& pass) {
208 size_t minimum_sampler_index = 100000000;
209 size_t buffer_index = 0;
210 size_t buffer_offset = 0;
211
212 for (const auto& uniform : runtime_stage_->GetUniforms()) {
213 std::shared_ptr<ShaderMetadata> metadata = MakeShaderMetadata(uniform);
214
215 switch (uniform.type) {
216 case kSampledImage: {
217 // Sampler uniforms are ordered in the IPLR according to their
218 // declaration and the uniform location reflects the correct offset to
219 // be mapped to - except that it may include all proceeding float
220 // uniforms. For example, a float sampler that comes after 4 float
221 // uniforms may have a location of 4. To convert to the actual offset
222 // we need to find the largest location assigned to a float uniform
223 // and then subtract this from all uniform locations. This is more or
224 // less the same operation we previously performed in the shader
225 // compiler.
226 minimum_sampler_index =
227 std::min(minimum_sampler_index, uniform.location);
228 break;
229 }
230 case kFloat: {
231 FML_DCHECK(renderer.GetContext()->GetBackendType() !=
232 Context::BackendType::kVulkan)
233 << "Uniform " << uniform.name
234 << " had unexpected type kFloat for Vulkan backend.";
235
236 size_t alignment =
237 std::max(uniform.bit_width / 8, DefaultUniformAlignment());
238 BufferView buffer_view = renderer.GetTransientsBuffer().Emplace(
239 uniform_data_->data() + buffer_offset, uniform.GetSize(),
240 alignment);
241
242 ShaderUniformSlot uniform_slot;
243 uniform_slot.name = uniform.name.c_str();
244 uniform_slot.ext_res_0 = uniform.location;
245 pass.BindResource(ShaderStage::kFragment,
246 DescriptorType::kUniformBuffer, uniform_slot,
247 metadata, std::move(buffer_view));
248 buffer_index++;
249 buffer_offset += uniform.GetSize();
250 break;
251 }
252 case kStruct: {
253 FML_DCHECK(renderer.GetContext()->GetBackendType() ==
254 Context::BackendType::kVulkan);
255 ShaderUniformSlot uniform_slot;
256 uniform_slot.name = uniform.name.c_str();
257 uniform_slot.binding = uniform.location;
258
259 // TODO(jonahwilliams): rewrite this to emplace directly into
260 // HostBuffer.
261 std::vector<float> uniform_buffer;
262 uniform_buffer.reserve(uniform.struct_layout.size());
263 size_t uniform_byte_index = 0u;
264 for (const auto& byte_type : uniform.struct_layout) {
265 if (byte_type == 0) {
266 uniform_buffer.push_back(0.f);
267 } else if (byte_type == 1) {
268 uniform_buffer.push_back(reinterpret_cast<float*>(
269 uniform_data_->data())[uniform_byte_index++]);
270 } else {
271 FML_UNREACHABLE();
272 }
273 }
274 size_t alignment = std::max(sizeof(float) * uniform_buffer.size(),
275 DefaultUniformAlignment());
276
277 BufferView buffer_view = renderer.GetTransientsBuffer().Emplace(
278 reinterpret_cast<const void*>(uniform_buffer.data()),
279 sizeof(float) * uniform_buffer.size(), alignment);
280 pass.BindResource(ShaderStage::kFragment,
281 DescriptorType::kUniformBuffer, uniform_slot,
282 ShaderMetadata{}, std::move(buffer_view));
283 }
284 }
285 }
286
287 size_t sampler_index = 0;
288 for (const auto& uniform : runtime_stage_->GetUniforms()) {
289 std::shared_ptr<ShaderMetadata> metadata = MakeShaderMetadata(uniform);
290
291 switch (uniform.type) {
292 case kSampledImage: {
293 FML_DCHECK(sampler_index < texture_inputs_.size());
294 auto& input = texture_inputs_[sampler_index];
295
296 const std::unique_ptr<const Sampler>& sampler =
297 context->GetSamplerLibrary()->GetSampler(
298 input.sampler_descriptor);
299
300 SampledImageSlot image_slot;
301 image_slot.name = uniform.name.c_str();
302 image_slot.binding = uniform.binding;
303 image_slot.texture_index = uniform.location - minimum_sampler_index;
304 pass.BindResource(ShaderStage::kFragment,
305 DescriptorType::kSampledImage, image_slot,
306 *metadata, input.texture, sampler);
307
308 sampler_index++;
309 break;
310 }
311 default:
312 continue;
313 }
314 }
315 return true;
316 };
317
318 /// Now that the descriptor set layouts are known, get the pipeline.
319 using VS = RuntimeEffectVertexShader;
320
321 PipelineBuilderCallback pipeline_callback =
322 [&](ContentContextOptions options) {
323 // Pipeline creation callback for the cache handler to call.
324 return renderer.GetCachedRuntimeEffectPipeline(
325 runtime_stage_->GetEntrypoint(), options, [&]() {
326 return CreatePipeline(renderer, options, /*async=*/false);
327 });
328 };
329
330 return ColorSourceContents::DrawGeometry<VS>(renderer, entity, pass,
331 pipeline_callback,
332 VS::FrameInfo{}, bind_callback);
333 }

References impeller::ShaderUniformSlot::binding, impeller::SampledImageSlot::binding, impeller::RenderPass::BindResource(), buffer_view, impeller::DefaultUniformAlignment(), impeller::HostBuffer::Emplace(), impeller::ShaderUniformSlot::ext_res_0, impeller::ContentContext::GetCachedRuntimeEffectPipeline(), impeller::ContentContext::GetContext(), impeller::ContentContext::GetTransientsBuffer(), impeller::kFloat, impeller::kFragment, impeller::kSampledImage, impeller::kStruct, impeller::kUniformBuffer, impeller::Context::kVulkan, impeller::MakeShaderMetadata(), impeller::ShaderUniformSlot::name, impeller::SampledImageSlot::name, and impeller::SampledImageSlot::texture_index.

## ◆ SetRuntimeStage()

void impeller::RuntimeEffectContents::SetRuntimeStage | ( | std::shared_ptr< RuntimeStage > | runtime_stage | ) |

Definition at line 27 of file runtime_effect_contents.cc.

28 {
29 runtime_stage_ = std::move(runtime_stage);
30 }

## ◆ SetTextureInputs()

void impeller::RuntimeEffectContents::SetTextureInputs | ( | std::vector< TextureInput > | texture_inputs | ) |

Definition at line 37 of file runtime_effect_contents.cc.

38 {
39 texture_inputs_ = std::move(texture_inputs);
40 }

## ◆ SetUniformData()

void impeller::RuntimeEffectContents::SetUniformData | ( | std::shared_ptr< std::vector< uint8_t >> | uniform_data | ) |

Definition at line 32 of file runtime_effect_contents.cc.

33 {
34 uniform_data_ = std::move(uniform_data);
35 }

The documentation for this class was generated from the following files:

- impeller/entity/contents/runtime_effect_contents.h
- impeller/entity/contents/runtime_effect_contents.cc

impeller::ColorSourceContents::PipelineBuilderCallback
std::function< std::shared_ptr< Pipeline< PipelineDescriptor > >(ContentContextOptions)> PipelineBuilderCallback
Definition: color_source_contents.h:114
impeller::kFloat
@ kFloat
Definition: runtime_types.h:23
impeller::MakeShaderMetadata
static std::shared_ptr< ShaderMetadata > MakeShaderMetadata(const RuntimeUniformDescription &uniform)
Definition: runtime_effect_contents.cc:57
impeller::DefaultUniformAlignment
constexpr size_t DefaultUniformAlignment()
Definition: platform.h:14
impeller::kSampledImage
@ kSampledImage
Definition: runtime_types.h:24
buffer_view
BufferView buffer_view
Definition: blit_command_gles.cc:127
impeller::VS
SolidFillVertexShader VS
Definition: stroke_path_geometry.cc:16
impeller::ShaderStage::kFragment
@ kFragment
impeller::kStruct
@ kStruct
Definition: runtime_types.h:25
impeller::DescriptorType::kSampledImage
@ kSampledImage
impeller::DescriptorType::kUniformBuffer
@ kUniformBuffer
impeller::Context::BackendType::kVulkan
@ kVulkan
impeller::ColorSourceContents::BindFragmentCallback
std::function< bool(RenderPass &pass)> BindFragmentCallback
Definition: color_source_contents.h:109