[Impeller] cache for text shadows. #166228

jonahwilliams · 2025-03-30T21:07:33Z

When rendering a text shadow, cache the resulting snapshot for at least one frame. Only attempts to content-aware hash for single glyphs (Icons). in other cases the exact layout may be different enough that its not worth trying to cache.

flutter-dashboard · 2025-04-01T00:05:25Z

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Changes reported for pull request #166228 at sha c9b908c

engine/src/flutter/impeller/display_list/canvas.cc

engine/src/flutter/impeller/display_list/dl_dispatcher.cc

engine/src/flutter/impeller/entity/contents/content_context.h

engine/src/flutter/impeller/entity/render_target_cache.cc

gaaclarke · 2025-04-01T00:16:58Z

engine/src/flutter/impeller/renderer/render_target.h

@@ -177,6 +177,12 @@ class RenderTargetAllocator {
      const std::shared_ptr<Texture>& existing_color_resolve_texture = nullptr,
      const std::shared_ptr<Texture>& existing_depth_stencil_texture = nullptr);

+  /// @brief Disable the cache until another call to enable.


This docstring talks about a cache but there is no description of anything as a cache in RenderTargetAllocator. The details of RenderTargetCache are creeping into its superclass. Can't we just put this into the render cache directly? When we call it we seem to know we have a RenderTargetCache (renderer.GetRenderTargetCache()->Enable();)

It is leaky, that is true. That said, if there is no cache then there is no harm in calling enable/disable.

I think the names RenderTargetAllocator::EnableCache RenderTargetAllocator::DisableCache make more sense since you aren't disabling the allocator.

engine/src/flutter/impeller/typographer/text_frame.cc

jonahwilliams · 2025-04-01T00:40:54Z

engine/src/flutter/impeller/display_list/canvas.cc

+  std::optional<Glyph> maybe_glyph = text_frame->AsSingleGlyph();
+  int64_t identifier = maybe_glyph.has_value()
+                           ? maybe_glyph.value().index
+                           : reinterpret_cast<int64_t>(text_frame.get());


question for @gaaclarke : is this safe/reasonable? The goal is only caching the same text frame. An alternative approach would be to have an ID system somewhere

I think so. Worst case scenario is that the text_frame gets copied and you get a cache miss. Since we have a std::shared_ptr to it I don't expect we'll copy it (but I wouldn't rule it out).

Doesn't the TextFrame have a font itself too? It's weird that we hash on the identifier which represents a font and have the font separately. Can the TextFrame be mutated?

Yeah hashing the font is for the "single glyph" optimization for Icons, but its unnecessary for the general text frame case.

flutter-dashboard · 2025-04-01T19:42:26Z

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Changes reported for pull request #166228 at sha efc7ee7

gaaclarke

lgtm! thanks

Roll Flutter from a0b1b3253416 to 02f13c37841f (37 revisions) flutter/flutter@a0b1b32...02f13c3 2025-04-03 [email protected] Roll Packages from 07496eb to 4a36dc6 (3 revisions) (flutter/flutter#166542) 2025-04-03 [email protected] Roll Skia from b67e53719e78 to 5f65df75febd (2 revisions) (flutter/flutter#166538) 2025-04-03 [email protected] Update docs to debug the Android embedder (flutter/flutter#166170) 2025-04-03 [email protected] Roll Dart SDK from 72562ca93bb5 to d174ec16c3ea (1 revision) (flutter/flutter#166525) 2025-04-03 [email protected] [macOS] Implement merged UI and platform thread (flutter/flutter#162883) 2025-04-03 [email protected] Roll Skia from f91412f5d89d to b67e53719e78 (1 revision) (flutter/flutter#166527) 2025-04-03 [email protected] Roll Packages from 125c117 to 07496eb (31 revisions) (flutter/flutter#166457) 2025-04-03 [email protected] Roll Skia from 2be12bc2668b to f91412f5d89d (2 revisions) (flutter/flutter#166517) 2025-04-03 [email protected] Roll Dart SDK from 2a1a13cc3a91 to 72562ca93bb5 (2 revisions) (flutter/flutter#166514) 2025-04-03 [email protected] [native_assets] Roll dependencies (flutter/flutter#166282) 2025-04-03 [email protected] Fix read only TextField focus traversal on macOS (flutter/flutter#166056) 2025-04-03 [email protected] Roll Skia from c106d7831592 to 2be12bc2668b (1 revision) (flutter/flutter#166509) 2025-04-03 [email protected] Roll Fuchsia Linux SDK from v7PGvypiiWLO8PbsZ... to vYisSsIgqw0mqFRVJ... (flutter/flutter#166508) 2025-04-03 [email protected] Roll Dart SDK from b8b4076b1237 to 2a1a13cc3a91 (1 revision) (flutter/flutter#166504) 2025-04-03 [email protected] Roll Skia from 75a0ec473181 to c106d7831592 (1 revision) (flutter/flutter#166499) 2025-04-03 [email protected] Migrate to Theme.brightnessOf method (flutter/flutter#163950) 2025-04-03 [email protected] Fix: Range slider show overlay for both thumbs on hovering one (flutter/flutter#165393) 2025-04-03 [email protected] Deprecate ExpansionTileController (flutter/flutter#166368) 2025-04-03 [email protected] Add styling parameters in `PopupMenuDivider` (flutter/flutter#164790) 2025-04-03 [email protected] Fix ISSUE_TEMPLATE Ordering: `10 < 9`, but `10 > 09` (flutter/flutter#166455) 2025-04-03 [email protected] Skip flaking scheduler test (flutter/flutter#166471) 2025-04-02 [email protected] Roll pub packages (flutter/flutter#166043) 2025-04-02 [email protected] [a11y] add SemanticsValidationResult (flutter/flutter#165935) 2025-04-02 [email protected] Remove unnecessary cache busting mechanism in hot restart (flutter/flutter#166295) 2025-04-02 [email protected] Roll Skia from 52cbb917fffd to 75a0ec473181 (21 revisions) (flutter/flutter#166484) 2025-04-02 [email protected] Started pixel aligning hairlines (flutter/flutter#166351) 2025-04-02 [email protected] Adds semantics role and adjust semantics for navigation bar (flutter/flutter#162467) 2025-04-02 [email protected] Reland "[skwasm] Dynamic Threading" (flutter/flutter#166454) 2025-04-02 [email protected] [dart:ui] Add `Path.addRSuperellipse` (flutter/flutter#166045) 2025-04-02 [email protected] Fix: Hero animation for page transition (flutter/flutter#164469) 2025-04-02 [email protected] Fix: DelegateTransition for cupertino sheet route (flutter/flutter#164675) 2025-04-02 [email protected] Roll Fuchsia Test Scripts from AEdsljKmUiPk92Wvv... to FZdRtNwH7jmADecj6... (flutter/flutter#166383) 2025-04-02 [email protected] [Impeller] cache for text shadows. (flutter/flutter#166228) 2025-04-02 [email protected] Convert `AppPluginLoaderPlugin` to Kotlin, and add `NativePluginLoaderReflectionBridge` to expose it in Kotlin (flutter/flutter#166027) 2025-04-02 [email protected] Roll Dart SDK from 4e1f02bc704f to b8b4076b1237 (7 revisions) (flutter/flutter#166474) 2025-04-02 [email protected] Update Roadmap (flutter/flutter#166332) 2025-04-02 [email protected] Update `CODEOWNERS` (flutter/flutter#166444) If this roll has caused a breakage, revert this CL and stop the roller using the controls here: https://autoroll.skia.org/r/flutter-packages Please CC [email protected],[email protected] on the revert to ensure that a human is aware of the problem. To file a bug in Packages: https://github.com/flutter/flutter/issues/new/choose ...

Roll Flutter from a0b1b3253416 to 02f13c37841f (37 revisions) flutter/flutter@a0b1b32...02f13c3 2025-04-03 [email protected] Roll Packages from d10d5af to 95f8e65 (3 revisions) (flutter/flutter#166542) 2025-04-03 [email protected] Roll Skia from b67e53719e78 to 5f65df75febd (2 revisions) (flutter/flutter#166538) 2025-04-03 [email protected] Update docs to debug the Android embedder (flutter/flutter#166170) 2025-04-03 [email protected] Roll Dart SDK from 72562ca93bb5 to d174ec16c3ea (1 revision) (flutter/flutter#166525) 2025-04-03 [email protected] [macOS] Implement merged UI and platform thread (flutter/flutter#162883) 2025-04-03 [email protected] Roll Skia from f91412f5d89d to b67e53719e78 (1 revision) (flutter/flutter#166527) 2025-04-03 [email protected] Roll Packages from 0d5d57b to d10d5af (31 revisions) (flutter/flutter#166457) 2025-04-03 [email protected] Roll Skia from 2be12bc2668b to f91412f5d89d (2 revisions) (flutter/flutter#166517) 2025-04-03 [email protected] Roll Dart SDK from 2a1a13cc3a91 to 72562ca93bb5 (2 revisions) (flutter/flutter#166514) 2025-04-03 [email protected] [native_assets] Roll dependencies (flutter/flutter#166282) 2025-04-03 [email protected] Fix read only TextField focus traversal on macOS (flutter/flutter#166056) 2025-04-03 [email protected] Roll Skia from c106d7831592 to 2be12bc2668b (1 revision) (flutter/flutter#166509) 2025-04-03 [email protected] Roll Fuchsia Linux SDK from v7PGvypiiWLO8PbsZ... to vYisSsIgqw0mqFRVJ... (flutter/flutter#166508) 2025-04-03 [email protected] Roll Dart SDK from b8b4076b1237 to 2a1a13cc3a91 (1 revision) (flutter/flutter#166504) 2025-04-03 [email protected] Roll Skia from 75a0ec473181 to c106d7831592 (1 revision) (flutter/flutter#166499) 2025-04-03 [email protected] Migrate to Theme.brightnessOf method (flutter/flutter#163950) 2025-04-03 [email protected] Fix: Range slider show overlay for both thumbs on hovering one (flutter/flutter#165393) 2025-04-03 [email protected] Deprecate ExpansionTileController (flutter/flutter#166368) 2025-04-03 [email protected] Add styling parameters in `PopupMenuDivider` (flutter/flutter#164790) 2025-04-03 [email protected] Fix ISSUE_TEMPLATE Ordering: `10 < 9`, but `10 > 09` (flutter/flutter#166455) 2025-04-03 [email protected] Skip flaking scheduler test (flutter/flutter#166471) 2025-04-02 [email protected] Roll pub packages (flutter/flutter#166043) 2025-04-02 [email protected] [a11y] add SemanticsValidationResult (flutter/flutter#165935) 2025-04-02 [email protected] Remove unnecessary cache busting mechanism in hot restart (flutter/flutter#166295) 2025-04-02 [email protected] Roll Skia from 52cbb917fffd to 75a0ec473181 (21 revisions) (flutter/flutter#166484) 2025-04-02 [email protected] Started pixel aligning hairlines (flutter/flutter#166351) 2025-04-02 [email protected] Adds semantics role and adjust semantics for navigation bar (flutter/flutter#162467) 2025-04-02 [email protected] Reland "[skwasm] Dynamic Threading" (flutter/flutter#166454) 2025-04-02 [email protected] [dart:ui] Add `Path.addRSuperellipse` (flutter/flutter#166045) 2025-04-02 [email protected] Fix: Hero animation for page transition (flutter/flutter#164469) 2025-04-02 [email protected] Fix: DelegateTransition for cupertino sheet route (flutter/flutter#164675) 2025-04-02 [email protected] Roll Fuchsia Test Scripts from AEdsljKmUiPk92Wvv... to FZdRtNwH7jmADecj6... (flutter/flutter#166383) 2025-04-02 [email protected] [Impeller] cache for text shadows. (flutter/flutter#166228) 2025-04-02 [email protected] Convert `AppPluginLoaderPlugin` to Kotlin, and add `NativePluginLoaderReflectionBridge` to expose it in Kotlin (flutter/flutter#166027) 2025-04-02 [email protected] Roll Dart SDK from 4e1f02bc704f to b8b4076b1237 (7 revisions) (flutter/flutter#166474) 2025-04-02 [email protected] Update Roadmap (flutter/flutter#166332) 2025-04-02 [email protected] Update `CODEOWNERS` (flutter/flutter#166444) If this roll has caused a breakage, revert this CL and stop the roller using the controls here: https://autoroll.skia.org/r/flutter-packages Please CC [email protected],[email protected] on the revert to ensure that a human is aware of the problem. To file a bug in Packages: https://github.com/flutter/flutter/issues/new/choose ...

[Impeller] cache for text shadows.

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github-actions bot added a: text input Entering text in a text field or keyboard related problems engine flutter/engine repository. See also e: labels. e: impeller Impeller rendering backend issues and features requests labels Mar 30, 2025

add some testing.

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jonahwilliams marked this pull request as ready for review March 31, 2025 20:02

test fixes and licenses.

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[Impeller] cache for text shadows. #166228

[Impeller] cache for text shadows. #166228

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