Flutter Impeller
content_context.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_ENTITY_CONTENTS_CONTENT_CONTEXT_H_
6 #define FLUTTER_IMPELLER_ENTITY_CONTENTS_CONTENT_CONTEXT_H_
7 
8 #include <initializer_list>
9 #include <memory>
10 #include <optional>
11 #include <unordered_map>
12 #include <utility>
13 
14 #include "flutter/fml/logging.h"
15 #include "flutter/fml/status_or.h"
17 #include "impeller/core/formats.h"
28 
29 namespace impeller {
30 /// Pipeline state configuration.
31 ///
32 /// Each unique combination of these options requires a different pipeline state
33 /// object to be built. This struct is used as a key for the per-pipeline
34 /// variant cache.
35 ///
36 /// When adding fields to this key, reliant features should take care to limit
37 /// the combinatorical explosion of variations. A sufficiently complicated
38 /// Flutter application may easily require building hundreds of PSOs in total,
39 /// but they shouldn't require e.g. 10s of thousands.
41  enum class StencilMode : uint8_t {
42  /// Turn the stencil test off. Used when drawing without stencil-then-cover
43  /// or overdraw prevention.
44  kIgnore,
45 
46  // Operations used for stencil-then-cover.
47 
48  /// Draw the stencil for the NonZero fill path rule.
49  ///
50  /// The stencil ref should always be 0 on commands using this mode.
52  /// Draw the stencil for the EvenOdd fill path rule.
53  ///
54  /// The stencil ref should always be 0 on commands using this mode.
56  /// Used for draw calls which fill in the stenciled area. Intended to be
57  /// used after `kStencilNonZeroFill` or `kStencilEvenOddFill` is used to set
58  /// up the stencil buffer. Also cleans up the stencil buffer by resetting
59  /// everything to zero.
60  ///
61  /// The stencil ref should always be 0 on commands using this mode.
63  /// The opposite of `kCoverCompare`. Used for draw calls which fill in the
64  /// non-stenciled area (intersection clips). Intended to be used after
65  /// `kStencilNonZeroFill` or `kStencilEvenOddFill` is used to set up the
66  /// stencil buffer. Also cleans up the stencil buffer by resetting
67  /// everything to zero.
68  ///
69  /// The stencil ref should always be 0 on commands using this mode.
71 
72  // Operations used for the "overdraw prevention" mechanism. This is used for
73  // drawing strokes.
74 
75  /// For each fragment, increment the stencil value if it's currently zero.
76  /// Discard fragments when the value is non-zero. This prevents
77  /// self-overlapping strokes from drawing over themselves.
78  ///
79  /// Note that this is done for rendering correctness, not performance. If a
80  /// stroke is drawn with a backdrop-reliant blend and self-intersects, then
81  /// the intersected geometry will render incorrectly when overdrawn because
82  /// we don't adjust the geometry prevent self-intersection.
83  ///
84  /// The stencil ref should always be 0 on commands using this mode.
86  /// Reset the stencil to a new maximum value specified by the ref (currently
87  /// always 0).
88  ///
89  /// The stencil ref should always be 0 on commands using this mode.
91  };
92 
100  bool depth_write_enabled = false;
102 
103  constexpr uint64_t ToKey() const {
104  static_assert(sizeof(sample_count) == 1);
105  static_assert(sizeof(blend_mode) == 1);
106  static_assert(sizeof(sample_count) == 1);
107  static_assert(sizeof(depth_compare) == 1);
108  static_assert(sizeof(stencil_mode) == 1);
109  static_assert(sizeof(primitive_type) == 1);
110  static_assert(sizeof(color_attachment_pixel_format) == 1);
111 
112  return (is_for_rrect_blur_clear ? 1llu : 0llu) << 0 |
113  (0) << 1 | // // Unused, previously wireframe.
114  (has_depth_stencil_attachments ? 1llu : 0llu) << 2 |
115  (depth_write_enabled ? 1llu : 0llu) << 3 |
116  // enums
117  static_cast<uint64_t>(color_attachment_pixel_format) << 8 |
118  static_cast<uint64_t>(primitive_type) << 16 |
119  static_cast<uint64_t>(stencil_mode) << 24 |
120  static_cast<uint64_t>(depth_compare) << 32 |
121  static_cast<uint64_t>(blend_mode) << 40 |
122  static_cast<uint64_t>(sample_count) << 48;
123  }
124 
126 };
127 
133 };
134 
135 class Tessellator;
136 class RenderTargetCache;
137 
139  public:
140  explicit ContentContext(
141  std::shared_ptr<Context> context,
142  std::shared_ptr<TypographerContext> typographer_context,
143  std::shared_ptr<RenderTargetAllocator> render_target_allocator = nullptr);
144 
146 
147  bool IsValid() const;
148 
149  Tessellator& GetTessellator() const;
150 
151  // clang-format off
229 #ifdef IMPELLER_ENABLE_OPENGLES
230  PipelineRef GetDownsampleTextureGlesPipeline(ContentContextOptions opts) const;
231  PipelineRef GetTiledTextureExternalPipeline(ContentContextOptions opts) const;
232  PipelineRef GetTiledTextureUvExternalPipeline(ContentContextOptions opts) const;
233 #endif // IMPELLER_ENABLE_OPENGLES
234  // clang-format on
235 
236  // An empty 1x1 texture for binding drawVertices/drawAtlas or other cases
237  // that don't always have a texture (due to blending).
238  std::shared_ptr<Texture> GetEmptyTexture() const;
239 
240  std::shared_ptr<Context> GetContext() const;
241 
242  const Capabilities& GetDeviceCapabilities() const;
243 
245  std::function<bool(const ContentContext&, RenderPass&)>;
246 
247  /// @brief Creates a new texture of size `texture_size` and calls
248  /// `subpass_callback` with a `RenderPass` for drawing to the texture.
249  fml::StatusOr<RenderTarget> MakeSubpass(
250  std::string_view label,
251  ISize texture_size,
252  const std::shared_ptr<CommandBuffer>& command_buffer,
253  const SubpassCallback& subpass_callback,
254  bool msaa_enabled = true,
255  bool depth_stencil_enabled = false,
256  int32_t mip_count = 1) const;
257 
258  /// Makes a subpass that will render to `subpass_target`.
259  fml::StatusOr<RenderTarget> MakeSubpass(
260  std::string_view label,
261  const RenderTarget& subpass_target,
262  const std::shared_ptr<CommandBuffer>& command_buffer,
263  const SubpassCallback& subpass_callback) const;
264 
265  const std::shared_ptr<LazyGlyphAtlas>& GetLazyGlyphAtlas() const {
266  return lazy_glyph_atlas_;
267  }
268 
269  const std::shared_ptr<RenderTargetAllocator>& GetRenderTargetCache() const {
270  return render_target_cache_;
271  }
272 
273  /// RuntimeEffect pipelines must be obtained via this method to avoid
274  /// re-creating them every frame.
275  ///
276  /// The unique_entrypoint_name comes from RuntimeEffect::GetEntrypoint.
277  /// Impellerc generates a unique entrypoint name for runtime effect shaders
278  /// based on the input file name and shader stage.
279  ///
280  /// The create_callback is synchronously invoked exactly once if a cached
281  /// pipeline is not found.
283  const std::string& unique_entrypoint_name,
284  const ContentContextOptions& options,
285  const std::function<std::shared_ptr<Pipeline<PipelineDescriptor>>()>&
286  create_callback) const;
287 
288  /// Used by hot reload/hot restart to clear a cached pipeline from
289  /// GetCachedRuntimeEffectPipeline.
291  const std::string& unique_entrypoint_name) const;
292 
293  /// @brief Retrieve the currnent host buffer for transient storage.
294  ///
295  /// This is only safe to use from the raster threads. Other threads should
296  /// allocate their own device buffers.
297  HostBuffer& GetTransientsBuffer() const { return *host_buffer_; }
298 
299  TextShadowCache& GetTextShadowCache() const { return *text_shadow_cache_; }
300 
301  protected:
302  // Visible for testing.
303  void SetTransientsBuffer(std::shared_ptr<HostBuffer> host_buffer) {
304  host_buffer_ = std::move(host_buffer);
305  }
306 
307  private:
308  std::shared_ptr<Context> context_;
309  std::shared_ptr<LazyGlyphAtlas> lazy_glyph_atlas_;
310 
311  /// Run backend specific additional setup and create common shader variants.
312  ///
313  /// This bootstrap is intended to improve the performance of several
314  /// first frame benchmarks that are tracked in the flutter device lab.
315  /// The workload includes initializing commonly used but not default
316  /// shader variants, as well as forcing driver initialization.
317  void InitializeCommonlyUsedShadersIfNeeded() const;
318 
319  struct RuntimeEffectPipelineKey {
320  std::string unique_entrypoint_name;
321  ContentContextOptions options;
322 
323  struct Hash {
324  std::size_t operator()(const RuntimeEffectPipelineKey& key) const {
325  return fml::HashCombine(key.unique_entrypoint_name,
326  key.options.ToKey());
327  }
328  };
329 
330  struct Equal {
331  inline bool operator()(const RuntimeEffectPipelineKey& lhs,
332  const RuntimeEffectPipelineKey& rhs) const {
333  return lhs.unique_entrypoint_name == rhs.unique_entrypoint_name &&
334  lhs.options.ToKey() == rhs.options.ToKey();
335  }
336  };
337  };
338 
339  mutable std::unordered_map<RuntimeEffectPipelineKey,
340  std::shared_ptr<Pipeline<PipelineDescriptor>>,
341  RuntimeEffectPipelineKey::Hash,
342  RuntimeEffectPipelineKey::Equal>
343  runtime_effect_pipelines_;
344 
345  struct Pipelines;
346  std::unique_ptr<Pipelines> pipelines_;
347 
348  bool is_valid_ = false;
349  std::shared_ptr<Tessellator> tessellator_;
350  std::shared_ptr<RenderTargetAllocator> render_target_cache_;
351  std::shared_ptr<HostBuffer> host_buffer_;
352  std::shared_ptr<Texture> empty_texture_;
353  std::unique_ptr<TextShadowCache> text_shadow_cache_;
354 
355  ContentContext(const ContentContext&) = delete;
356 
357  ContentContext& operator=(const ContentContext&) = delete;
358 };
359 
360 } // namespace impeller
361 
362 #endif // FLUTTER_IMPELLER_ENTITY_CONTENTS_CONTENT_CONTEXT_H_
PipelineRef GetBlendLuminosityPipeline(ContentContextOptions opts) const
HostBuffer & GetTransientsBuffer() const
Retrieve the currnent host buffer for transient storage.
PipelineRef GetTiledTexturePipeline(ContentContextOptions opts) const
PipelineRef GetFramebufferBlendColorPipeline(ContentContextOptions opts) const
PipelineRef GetDownsamplePipeline(ContentContextOptions opts) const
PipelineRef GetSourceInBlendPipeline(ContentContextOptions opts) const
void ClearCachedRuntimeEffectPipeline(const std::string &unique_entrypoint_name) const
PipelineRef GetLinearGradientFillPipeline(ContentContextOptions opts) const
PipelineRef GetFramebufferBlendOverlayPipeline(ContentContextOptions opts) const
PipelineRef GetBlendColorDodgePipeline(ContentContextOptions opts) const
PipelineRef GetFramebufferBlendColorBurnPipeline(ContentContextOptions opts) const
void SetTransientsBuffer(std::shared_ptr< HostBuffer > host_buffer)
PipelineRef GetPorterDuffPipeline(BlendMode mode, ContentContextOptions opts) const
std::shared_ptr< Texture > GetEmptyTexture() const
PipelineRef GetSourceOutBlendPipeline(ContentContextOptions opts) const
PipelineRef GetScreenBlendPipeline(ContentContextOptions opts) const
PipelineRef GetBlendColorPipeline(ContentContextOptions opts) const
PipelineRef GetLinePipeline(ContentContextOptions opts) const
PipelineRef GetFramebufferBlendLuminosityPipeline(ContentContextOptions opts) const
PipelineRef GetPlusBlendPipeline(ContentContextOptions opts) const
PipelineRef GetFastGradientPipeline(ContentContextOptions opts) const
const std::shared_ptr< LazyGlyphAtlas > & GetLazyGlyphAtlas() const
ContentContext(std::shared_ptr< Context > context, std::shared_ptr< TypographerContext > typographer_context, std::shared_ptr< RenderTargetAllocator > render_target_allocator=nullptr)
PipelineRef GetSolidFillPipeline(ContentContextOptions opts) const
fml::StatusOr< RenderTarget > MakeSubpass(std::string_view label, ISize texture_size, const std::shared_ptr< CommandBuffer > &command_buffer, 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...
const Capabilities & GetDeviceCapabilities() const
PipelineRef GetModulateBlendPipeline(ContentContextOptions opts) const
PipelineRef GetFramebufferBlendHardLightPipeline(ContentContextOptions opts) const
PipelineRef GetFramebufferBlendColorDodgePipeline(ContentContextOptions opts) const
PipelineRef GetSweepGradientUniformFillPipeline(ContentContextOptions opts) const
PipelineRef GetBlendSoftLightPipeline(ContentContextOptions opts) const
PipelineRef GetDestinationATopBlendPipeline(ContentContextOptions opts) const
PipelineRef GetTextureStrictSrcPipeline(ContentContextOptions opts) const
PipelineRef GetCachedRuntimeEffectPipeline(const std::string &unique_entrypoint_name, const ContentContextOptions &options, const std::function< std::shared_ptr< Pipeline< PipelineDescriptor >>()> &create_callback) const
PipelineRef GetRadialGradientSSBOFillPipeline(ContentContextOptions opts) const
PipelineRef GetBlendColorBurnPipeline(ContentContextOptions opts) const
PipelineRef GetSweepGradientSSBOFillPipeline(ContentContextOptions opts) const
PipelineRef GetLinearGradientUniformFillPipeline(ContentContextOptions opts) const
PipelineRef GetFramebufferBlendScreenPipeline(ContentContextOptions opts) const
PipelineRef GetLinearGradientSSBOFillPipeline(ContentContextOptions opts) const
PipelineRef GetRadialGradientFillPipeline(ContentContextOptions opts) const
PipelineRef GetTexturePipeline(ContentContextOptions opts) const
PipelineRef GetBlendHardLightPipeline(ContentContextOptions opts) const
PipelineRef GetClearBlendPipeline(ContentContextOptions opts) const
PipelineRef GetConicalGradientUniformFillPipeline(ContentContextOptions opts, ConicalKind kind) const
PipelineRef GetRadialGradientUniformFillPipeline(ContentContextOptions opts) const
PipelineRef GetSweepGradientFillPipeline(ContentContextOptions opts) const
PipelineRef GetFramebufferBlendExclusionPipeline(ContentContextOptions opts) const
PipelineRef GetFramebufferBlendDarkenPipeline(ContentContextOptions opts) const
PipelineRef GetBlendSaturationPipeline(ContentContextOptions opts) const
PipelineRef GetFramebufferBlendSoftLightPipeline(ContentContextOptions opts) const
PipelineRef GetFramebufferBlendLightenPipeline(ContentContextOptions opts) const
PipelineRef GetMorphologyFilterPipeline(ContentContextOptions opts) const
PipelineRef GetFramebufferBlendSaturationPipeline(ContentContextOptions opts) const
PipelineRef GetBlendDifferencePipeline(ContentContextOptions opts) const
PipelineRef GetGaussianBlurPipeline(ContentContextOptions opts) const
PipelineRef GetBlendHuePipeline(ContentContextOptions opts) const
PipelineRef GetSrgbToLinearFilterPipeline(ContentContextOptions opts) const
PipelineRef GetDestinationOutBlendPipeline(ContentContextOptions opts) const
PipelineRef GetYUVToRGBFilterPipeline(ContentContextOptions opts) const
PipelineRef GetFramebufferBlendDifferencePipeline(ContentContextOptions opts) const
PipelineRef GetFramebufferBlendHuePipeline(ContentContextOptions opts) const
PipelineRef GetSourceATopBlendPipeline(ContentContextOptions opts) const
PipelineRef GetXorBlendPipeline(ContentContextOptions opts) const
PipelineRef GetGlyphAtlasPipeline(ContentContextOptions opts) const
PipelineRef GetClipPipeline(ContentContextOptions opts) const
const std::shared_ptr< RenderTargetAllocator > & GetRenderTargetCache() const
PipelineRef GetRRectBlurPipeline(ContentContextOptions opts) const
PipelineRef GetBlendScreenPipeline(ContentContextOptions opts) const
std::function< bool(const ContentContext &, RenderPass &)> SubpassCallback
PipelineRef GetBlendDarkenPipeline(ContentContextOptions opts) const
PipelineRef GetSourceBlendPipeline(ContentContextOptions opts) const
PipelineRef GetLinearToSrgbFilterPipeline(ContentContextOptions opts) const
TextShadowCache & GetTextShadowCache() const
PipelineRef GetBlendOverlayPipeline(ContentContextOptions opts) const
PipelineRef GetDestinationBlendPipeline(ContentContextOptions opts) const
PipelineRef GetDestinationOverBlendPipeline(ContentContextOptions opts) const
PipelineRef GetFramebufferBlendMultiplyPipeline(ContentContextOptions opts) const
PipelineRef GetConicalGradientSSBOFillPipeline(ContentContextOptions opts, ConicalKind kind) const
Tessellator & GetTessellator() const
PipelineRef GetBlendLightenPipeline(ContentContextOptions opts) const
PipelineRef GetBlendMultiplyPipeline(ContentContextOptions opts) const
PipelineRef GetSourceOverBlendPipeline(ContentContextOptions opts) const
PipelineRef GetBlendExclusionPipeline(ContentContextOptions opts) const
PipelineRef GetColorMatrixColorFilterPipeline(ContentContextOptions opts) const
PipelineRef GetConicalGradientFillPipeline(ContentContextOptions opts, ConicalKind kind) const
std::shared_ptr< Context > GetContext() const
PipelineRef GetDestinationInBlendPipeline(ContentContextOptions opts) const
PipelineRef GetRSuperellipseBlurPipeline(ContentContextOptions opts) const
PipelineRef GetBorderMaskBlurPipeline(ContentContextOptions opts) const
PipelineRef GetDrawVerticesUberPipeline(BlendMode blend_mode, ContentContextOptions opts) const
Render passes encode render commands directed as one specific render target into an underlying comman...
Definition: render_pass.h:30
A utility that generates triangles of the specified fill type given a polyline. This happens on the C...
Definition: tessellator.h:37
A cache for blurred text that re-uses these across frames.
std::vector< std::pair< uint64_t, std::unique_ptr< GenericRenderPipelineHandle > > > pipelines_
PrimitiveType
Decides how backend draws pixels based on input vertices.
Definition: formats.h:352
PixelFormat
The Pixel formats supported by Impeller. The naming convention denotes the usage of the component,...
Definition: formats.h:99
CompareFunction
Definition: formats.h:552
@ kAlways
Comparison test passes always passes.
BlendMode
Definition: color.h:58
SampleCount
Definition: formats.h:295
bool operator()(const RuntimeEffectPipelineKey &lhs, const RuntimeEffectPipelineKey &rhs) const
std::size_t operator()(const RuntimeEffectPipelineKey &key) const
void ApplyToPipelineDescriptor(PipelineDescriptor &desc) const
constexpr uint64_t ToKey() const