[Impeller] GLES: lazily allocate texture mip levels on first per-level write#186302
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This pull request modifies the GLES backend to allocate the complete mipmap chain using glTexImage2D during texture initialization and buffer-to-texture blit operations, ensuring storage is defined for all levels before sub-image updates. Review feedback highlights that the implementation in TextureGLES currently assumes a 2D texture target and needs to be updated to support cubemap faces. Furthermore, it is suggested to refactor the redundant mipmap dimension calculation and allocation logic into a shared helper method to reduce code duplication.
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…l write `glTexSubImage2D` into a level not previously defined by `glTexImage2D` raises `GL_INVALID_OPERATION`. Both the lazy slice-init in `BlitCopyBufferToTextureCommandGLES::Encode` and `TextureGLES::InitializeContentsIfNecessary` only ever allocated level 0, so any non-zero mip upload aborted with a fatal GL error. The pre-existing `InitializeContentsIfNecessary` cubemap path was also broken: it would re-bind a `GL_TEXTURE_CUBE_MAP` handle to `GL_TEXTURE_2D` and call `glTexImage2D` on the wrong target (latent crash on first cubemap sampler bind without prior upload). Switch to per-`(slice, mip_level)` initialization tracking and allocate each level lazily on its first write: - `slices_initialized_` becomes `std::array<std::bitset<16>, 6>` (per-slice, per-mip). - `InitializeContentsIfNecessary` allocates only the base mip level (matching the pre-fix call count, so Impeller's snapshot pipeline keeps its `glGenerateMipmap`-driven allocation pattern unchanged). For cubemaps it now correctly binds `GL_TEXTURE_CUBE_MAP` and allocates the base level for each of the six face targets. - `BlitCopyBufferToTextureCommandGLES::Encode` allocates the requested `(slice, mip_level)` lazily before `glTexSubImage2D`, so non-zero mip uploads find storage already defined while existing single-level uploads pay no extra cost. Cubemap face targets and the per-(slice, mip) helpers are exercised by new `BlitCommandGLES` unit tests; the `glTexImage2D` and `glBindTexture` mocks in `MockGLES` are wired up to support them. Verified locally with flutter_tester_opengles --enable-flutter-gpu against the multi-mip gpu_test.dart from flutter#185890: the new "Texture.overwrite writes to a non-zero mip level" and cubemap-face tests pass on the GLES backend.
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…tests The structured-binding loop variable copies a shared_ptr each iteration; take it by const reference instead.
gaaclarke
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mostly looks good, there is some existing problems this is building off of that would be nice to avoid
| /// always 0). | ||
| /// @param[in] mip_level The mip level whose storage was allocated. | ||
| /// | ||
| void MarkSliceMipLevelInitialized(size_t slice, size_t mip_level) const; |
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I know you are following the existing pattern, but this is function for mutating, this shouldn't be a const function.
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Yeah I agree, this is all sorts of wonky, and would be happy to clean it up. Would you mind if I deferred the full cleanup of the Texture mutation chain to a follow-up PR? Filed an issue: #186371
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Ah actually, thinking about this a bit more, the underlying mutable usage here seems like the canonical use case. GLES-specific lazy allocation tracking is purely an implementation detail (Metal and Vulkan allocate the full mip chain upfront and don't need any of this). Making the method non-const would force stuff like Bind() and SetAsFramebufferAttachment() to be non-const too, propagating a GLES-driver workaround into the type signatures across everything using the higher abstraction. I'd lean toward keeping MarkSliceMipLevelInitialized const for symmetry with MarkSliceInitialized, but happy to revert the MarkContentsInitialized() const change in this PR so we're not extending the pattern any further than necessary. Thoughts?
I don't wanna land this and then bait & switch you haha.
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The whole thing seems fukakta, TextureGLES::InitializeContentsIfNecessary() is a const method too.
Yea, give it a shot if it becomes too much of a hassle let's stop the bleeding by not following that pattern here if we can avoid it.
propagating a GLES-driver workaround into the type signatures across everything using the higher abstraction.
Maybe if the mutable was percolated up it would make more sense than where it is now?
Give it a shot and if it get's hairy we can save it for another day.
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(this is fine for now, feel free to explore outside of this pr)
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Maybe if the mutable was percolated up it would make more sense than where it is now?
That's an interesting idea. Okay, I repurposed the issue and will land + see if I can make the weirdness down here better.
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I tried it out and it was really easy to do: e36064c
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Ah thanks, I'll just do it in this PR then
| /// always 0). | ||
| /// @param[in] mip_level The mip level whose storage was allocated. | ||
| /// | ||
| void MarkSliceMipLevelInitialized(size_t slice, size_t mip_level) const; |
| // `fence_`). The mutation is implementation detail of the GLES backend | ||
| // and is invisible to the higher abstraction; the `const_cast` is | ||
| // confined to this one call site. | ||
| if (!const_cast<TextureGLES&>(texture_gles).Bind()) { |
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Doh, i didn't realize this got added. This is probably equally bad as the mutable instance variables. Sorry about that, thanks for the comment. Either way.
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autosubmit label was removed for flutter/flutter/186302, because - The status or check suite Windows tool_integration_tests_4_10 has failed. Please fix the issues identified (or deflake) before re-applying this label. |
Roll Flutter from 707dbc0420a3 to 23f6f5853f50 (149 revisions) flutter/flutter@707dbc0...23f6f58 2026-05-12 [email protected] Add 'cp: review' label to the manual cherrypick process (flutter/flutter#186158) 2026-05-12 [email protected] Roll Packages from 19ec8b8 to 93cbed6 (3 revisions) (flutter/flutter#186401) 2026-05-12 [email protected] Removes SDF option for macOS (always enabled) (flutter/flutter#186265) 2026-05-12 [email protected] docs: fix typos in flutter_tools comments (flutter/flutter#186321) 2026-05-12 [email protected] Pass XcodeBasedProject instead of String to functions in XcodeProjectInterpreter (flutter/flutter#186378) 2026-05-12 [email protected] Update iOS scenario app test goldens to match changes from flutter/flutter#182662 (flutter/flutter#186390) 2026-05-12 [email protected] Roll Skia from ad0aff15b9fa to 77a21bc723dc (2 revisions) (flutter/flutter#186396) 2026-05-12 [email protected] Migrate focus_node.unfocus.0.dart to use `RadioGroup` (flutter/flutter#183979) 2026-05-12 [email protected] Roll Skia from 91d3c1e730af to ad0aff15b9fa (7 revisions) (flutter/flutter#186391) 2026-05-12 [email protected] [Flutter GPU] Allow customizing the vertex layout on a RenderPipeline (flutter/flutter#186310) 2026-05-12 [email protected] Fix `EmbedderTest.CanRenderTextWithImpellerMetal` test breakage (flutter/flutter#186262) 2026-05-12 [email protected] Roll Fuchsia Linux SDK from rFhU-YPqdCRCtCz7b... to z7ICmPtn4hspu02zk... (flutter/flutter#186384) 2026-05-12 [email protected] [Impeller] GLES: lazily allocate texture mip levels on first per-level write (flutter/flutter#186302) 2026-05-12 [email protected] [Android] Propagate --enable-flutter-gpu Intent extra to engine args (flutter/flutter#186298) 2026-05-11 [email protected] [ci] update no-response workflow to also look for old label name in e… (flutter/flutter#186373) 2026-05-11 [email protected] [ImpellerC] Write a depfile when --shader-bundle is in use (flutter/flutter#186341) 2026-05-11 [email protected] docs: fix doubled-word typos in comments (flutter/flutter#186320) 2026-05-11 [email protected] Roll Skia from 32281401997e to 91d3c1e730af (4 revisions) (flutter/flutter#186368) 2026-05-11 [email protected] Show SwiftPM warnings right before iOS/macOS build (flutter/flutter#185984) 2026-05-11 [email protected] Convert rebuilding-flutter-tool script to dart (flutter/flutter#185089) 2026-05-11 [email protected] Use Xcode's LLDB (flutter/flutter#186273) 2026-05-11 [email protected] Remove `currentMainUri` from `generateMainDartWithPluginRegistrant` (flutter/flutter#185907) 2026-05-11 [email protected] Roll Skia from 2514f6b5f92b to 32281401997e (1 revision) (flutter/flutter#186349) 2026-05-11 [email protected] Roll Packages from 92552b1 to 19ec8b8 (4 revisions) (flutter/flutter#186350) 2026-05-11 [email protected] Check for absolute paths in skills. (flutter/flutter#185632) 2026-05-11 [email protected] Roll Skia from 9fb7d2814642 to 2514f6b5f92b (1 revision) (flutter/flutter#186347) 2026-05-11 [email protected] Roll Skia from 8cafb209e836 to 9fb7d2814642 (4 revisions) (flutter/flutter#186335) 2026-05-10 [email protected] Roll Fuchsia Linux SDK from sOBiPJb0xznDBZlf5... to rFhU-YPqdCRCtCz7b... (flutter/flutter#186328) 2026-05-10 [email protected] Roll Skia from 05a03f99c74e to 8cafb209e836 (1 revision) (flutter/flutter#186315) 2026-05-10 [email protected] [Impeller] Vulkan: don't drop user-supplied viewport X, Y, and depth range (flutter/flutter#185886) 2026-05-09 [email protected] Update Fuchsia tests to subpackage their child components (flutter/flutter#186259) 2026-05-09 [email protected] Fix SelectableText crash with inline lambda contextMenuBuilder (flutter/flutter#184990) 2026-05-09 [email protected] Roll Fuchsia Linux SDK from 5_TnhTsHSqtCx37o6... to sOBiPJb0xznDBZlf5... (flutter/flutter#186289) 2026-05-09 [email protected] Roll Skia from dc78d4bd2efb to 05a03f99c74e (2 revisions) (flutter/flutter#186283) 2026-05-09 [email protected] Improve non rect platform view rendering (flutter/flutter#182662) 2026-05-08 [email protected] Roll Skia from 31521f8508c7 to dc78d4bd2efb (1 revision) (flutter/flutter#186278) 2026-05-08 [email protected] Moves wide_gamut_macos to arm64 (flutter/flutter#186214) 2026-05-08 98614782+auto-submit[bot]@users.noreply.github.com Reverts "[iOS] Migrate VSyncClient to a pure Obj-C implementation (#186166)" (flutter/flutter#186266) 2026-05-08 [email protected] Roll Skia from a00db8749edb to 31521f8508c7 (2 revisions) (flutter/flutter#186264) 2026-05-08 [email protected] Optimize compatible `DrawDiffRoundRect` calls to use `DrawRoundRect` (flutter/flutter#186203) 2026-05-08 [email protected] [triage] Add Flutter GPU as a triage team (flutter/flutter#186263) 2026-05-08 [email protected] doc: Unified Check-Run User manual (flutter/flutter#186210) 2026-05-08 [email protected] Roll Skia from 5f7adf4403d6 to a00db8749edb (1 revision) (flutter/flutter#186257) 2026-05-08 [email protected] Roll Packages from 0411f1d to 92552b1 (1 revision) (flutter/flutter#186256) 2026-05-08 [email protected] Add logging to figure out jvm crashes for `hot_mode_tests` (flutter/flutter#186107) 2026-05-08 [email protected] Roll Skia from 926c09741ce2 to 5f7adf4403d6 (3 revisions) (flutter/flutter#186242) ...
Roll Flutter from 707dbc0420a3 to 23f6f5853f50 (149 revisions) flutter/flutter@707dbc0...23f6f58 2026-05-12 [email protected] Add 'cp: review' label to the manual cherrypick process (flutter/flutter#186158) 2026-05-12 [email protected] Roll Packages from 19ec8b861676 to 93cbed65f336 (3 revisions) (flutter/flutter#186401) 2026-05-12 [email protected] Removes SDF option for macOS (always enabled) (flutter/flutter#186265) 2026-05-12 [email protected] docs: fix typos in flutter_tools comments (flutter/flutter#186321) 2026-05-12 [email protected] Pass XcodeBasedProject instead of String to functions in XcodeProjectInterpreter (flutter/flutter#186378) 2026-05-12 [email protected] Update iOS scenario app test goldens to match changes from flutter/flutter#182662 (flutter/flutter#186390) 2026-05-12 [email protected] Roll Skia from ad0aff15b9fa to 77a21bc723dc (2 revisions) (flutter/flutter#186396) 2026-05-12 [email protected] Migrate focus_node.unfocus.0.dart to use `RadioGroup` (flutter/flutter#183979) 2026-05-12 [email protected] Roll Skia from 91d3c1e730af to ad0aff15b9fa (7 revisions) (flutter/flutter#186391) 2026-05-12 [email protected] [Flutter GPU] Allow customizing the vertex layout on a RenderPipeline (flutter/flutter#186310) 2026-05-12 [email protected] Fix `EmbedderTest.CanRenderTextWithImpellerMetal` test breakage (flutter/flutter#186262) 2026-05-12 [email protected] Roll Fuchsia Linux SDK from rFhU-YPqdCRCtCz7b... to z7ICmPtn4hspu02zk... (flutter/flutter#186384) 2026-05-12 [email protected] [Impeller] GLES: lazily allocate texture mip levels on first per-level write (flutter/flutter#186302) 2026-05-12 [email protected] [Android] Propagate --enable-flutter-gpu Intent extra to engine args (flutter/flutter#186298) 2026-05-11 [email protected] [ci] update no-response workflow to also look for old label name in e… (flutter/flutter#186373) 2026-05-11 [email protected] [ImpellerC] Write a depfile when --shader-bundle is in use (flutter/flutter#186341) 2026-05-11 [email protected] docs: fix doubled-word typos in comments (flutter/flutter#186320) 2026-05-11 [email protected] Roll Skia from 32281401997e to 91d3c1e730af (4 revisions) (flutter/flutter#186368) 2026-05-11 [email protected] Show SwiftPM warnings right before iOS/macOS build (flutter/flutter#185984) 2026-05-11 [email protected] Convert rebuilding-flutter-tool script to dart (flutter/flutter#185089) 2026-05-11 [email protected] Use Xcode's LLDB (flutter/flutter#186273) 2026-05-11 [email protected] Remove `currentMainUri` from `generateMainDartWithPluginRegistrant` (flutter/flutter#185907) 2026-05-11 [email protected] Roll Skia from 2514f6b5f92b to 32281401997e (1 revision) (flutter/flutter#186349) 2026-05-11 [email protected] Roll Packages from 92552b16bcc1 to 19ec8b861676 (4 revisions) (flutter/flutter#186350) 2026-05-11 [email protected] Check for absolute paths in skills. (flutter/flutter#185632) 2026-05-11 [email protected] Roll Skia from 9fb7d2814642 to 2514f6b5f92b (1 revision) (flutter/flutter#186347) 2026-05-11 [email protected] Roll Skia from 8cafb209e836 to 9fb7d2814642 (4 revisions) (flutter/flutter#186335) 2026-05-10 [email protected] Roll Fuchsia Linux SDK from sOBiPJb0xznDBZlf5... to rFhU-YPqdCRCtCz7b... (flutter/flutter#186328) 2026-05-10 [email protected] Roll Skia from 05a03f99c74e to 8cafb209e836 (1 revision) (flutter/flutter#186315) 2026-05-10 [email protected] [Impeller] Vulkan: don't drop user-supplied viewport X, Y, and depth range (flutter/flutter#185886) 2026-05-09 [email protected] Update Fuchsia tests to subpackage their child components (flutter/flutter#186259) 2026-05-09 [email protected] Fix SelectableText crash with inline lambda contextMenuBuilder (flutter/flutter#184990) 2026-05-09 [email protected] Roll Fuchsia Linux SDK from 5_TnhTsHSqtCx37o6... to sOBiPJb0xznDBZlf5... (flutter/flutter#186289) 2026-05-09 [email protected] Roll Skia from dc78d4bd2efb to 05a03f99c74e (2 revisions) (flutter/flutter#186283) 2026-05-09 [email protected] Improve non rect platform view rendering (flutter/flutter#182662) 2026-05-08 [email protected] Roll Skia from 31521f8508c7 to dc78d4bd2efb (1 revision) (flutter/flutter#186278) 2026-05-08 [email protected] Moves wide_gamut_macos to arm64 (flutter/flutter#186214) 2026-05-08 98614782+auto-submit[bot]@users.noreply.github.com Reverts "[iOS] Migrate VSyncClient to a pure Obj-C implementation (#186166)" (flutter/flutter#186266) 2026-05-08 [email protected] Roll Skia from a00db8749edb to 31521f8508c7 (2 revisions) (flutter/flutter#186264) 2026-05-08 [email protected] Optimize compatible `DrawDiffRoundRect` calls to use `DrawRoundRect` (flutter/flutter#186203) 2026-05-08 [email protected] [triage] Add Flutter GPU as a triage team (flutter/flutter#186263) 2026-05-08 [email protected] doc: Unified Check-Run User manual (flutter/flutter#186210) 2026-05-08 [email protected] Roll Skia from 5f7adf4403d6 to a00db8749edb (1 revision) (flutter/flutter#186257) 2026-05-08 [email protected] Roll Packages from cfdd1d3 to 92552b16bcc1 (1 revision) (flutter/flutter#186256) 2026-05-08 [email protected] Add logging to figure out jvm crashes for `hot_mode_tests` (flutter/flutter#186107) 2026-05-08 [email protected] Roll Skia from 926c09741ce2 to 5f7adf4403d6 (3 revisions) (flutter/flutter#186242) ...
…er#11700) Roll Flutter from 707dbc0420a3 to 23f6f5853f50 (149 revisions) flutter/flutter@707dbc0...23f6f58 2026-05-12 [email protected] Add 'cp: review' label to the manual cherrypick process (flutter/flutter#186158) 2026-05-12 [email protected] Roll Packages from 19ec8b8 to 93cbed6 (3 revisions) (flutter/flutter#186401) 2026-05-12 [email protected] Removes SDF option for macOS (always enabled) (flutter/flutter#186265) 2026-05-12 [email protected] docs: fix typos in flutter_tools comments (flutter/flutter#186321) 2026-05-12 [email protected] Pass XcodeBasedProject instead of String to functions in XcodeProjectInterpreter (flutter/flutter#186378) 2026-05-12 [email protected] Update iOS scenario app test goldens to match changes from flutter/flutter#182662 (flutter/flutter#186390) 2026-05-12 [email protected] Roll Skia from ad0aff15b9fa to 77a21bc723dc (2 revisions) (flutter/flutter#186396) 2026-05-12 [email protected] Migrate focus_node.unfocus.0.dart to use `RadioGroup` (flutter/flutter#183979) 2026-05-12 [email protected] Roll Skia from 91d3c1e730af to ad0aff15b9fa (7 revisions) (flutter/flutter#186391) 2026-05-12 [email protected] [Flutter GPU] Allow customizing the vertex layout on a RenderPipeline (flutter/flutter#186310) 2026-05-12 [email protected] Fix `EmbedderTest.CanRenderTextWithImpellerMetal` test breakage (flutter/flutter#186262) 2026-05-12 [email protected] Roll Fuchsia Linux SDK from rFhU-YPqdCRCtCz7b... to z7ICmPtn4hspu02zk... (flutter/flutter#186384) 2026-05-12 [email protected] [Impeller] GLES: lazily allocate texture mip levels on first per-level write (flutter/flutter#186302) 2026-05-12 [email protected] [Android] Propagate --enable-flutter-gpu Intent extra to engine args (flutter/flutter#186298) 2026-05-11 [email protected] [ci] update no-response workflow to also look for old label name in e… (flutter/flutter#186373) 2026-05-11 [email protected] [ImpellerC] Write a depfile when --shader-bundle is in use (flutter/flutter#186341) 2026-05-11 [email protected] docs: fix doubled-word typos in comments (flutter/flutter#186320) 2026-05-11 [email protected] Roll Skia from 32281401997e to 91d3c1e730af (4 revisions) (flutter/flutter#186368) 2026-05-11 [email protected] Show SwiftPM warnings right before iOS/macOS build (flutter/flutter#185984) 2026-05-11 [email protected] Convert rebuilding-flutter-tool script to dart (flutter/flutter#185089) 2026-05-11 [email protected] Use Xcode's LLDB (flutter/flutter#186273) 2026-05-11 [email protected] Remove `currentMainUri` from `generateMainDartWithPluginRegistrant` (flutter/flutter#185907) 2026-05-11 [email protected] Roll Skia from 2514f6b5f92b to 32281401997e (1 revision) (flutter/flutter#186349) 2026-05-11 [email protected] Roll Packages from 92552b1 to 19ec8b8 (4 revisions) (flutter/flutter#186350) 2026-05-11 [email protected] Check for absolute paths in skills. (flutter/flutter#185632) 2026-05-11 [email protected] Roll Skia from 9fb7d2814642 to 2514f6b5f92b (1 revision) (flutter/flutter#186347) 2026-05-11 [email protected] Roll Skia from 8cafb209e836 to 9fb7d2814642 (4 revisions) (flutter/flutter#186335) 2026-05-10 [email protected] Roll Fuchsia Linux SDK from sOBiPJb0xznDBZlf5... to rFhU-YPqdCRCtCz7b... (flutter/flutter#186328) 2026-05-10 [email protected] Roll Skia from 05a03f99c74e to 8cafb209e836 (1 revision) (flutter/flutter#186315) 2026-05-10 [email protected] [Impeller] Vulkan: don't drop user-supplied viewport X, Y, and depth range (flutter/flutter#185886) 2026-05-09 [email protected] Update Fuchsia tests to subpackage their child components (flutter/flutter#186259) 2026-05-09 [email protected] Fix SelectableText crash with inline lambda contextMenuBuilder (flutter/flutter#184990) 2026-05-09 [email protected] Roll Fuchsia Linux SDK from 5_TnhTsHSqtCx37o6... to sOBiPJb0xznDBZlf5... (flutter/flutter#186289) 2026-05-09 [email protected] Roll Skia from dc78d4bd2efb to 05a03f99c74e (2 revisions) (flutter/flutter#186283) 2026-05-09 [email protected] Improve non rect platform view rendering (flutter/flutter#182662) 2026-05-08 [email protected] Roll Skia from 31521f8508c7 to dc78d4bd2efb (1 revision) (flutter/flutter#186278) 2026-05-08 [email protected] Moves wide_gamut_macos to arm64 (flutter/flutter#186214) 2026-05-08 98614782+auto-submit[bot]@users.noreply.github.com Reverts "[iOS] Migrate VSyncClient to a pure Obj-C implementation (#186166)" (flutter/flutter#186266) 2026-05-08 [email protected] Roll Skia from a00db8749edb to 31521f8508c7 (2 revisions) (flutter/flutter#186264) 2026-05-08 [email protected] Optimize compatible `DrawDiffRoundRect` calls to use `DrawRoundRect` (flutter/flutter#186203) 2026-05-08 [email protected] [triage] Add Flutter GPU as a triage team (flutter/flutter#186263) 2026-05-08 [email protected] doc: Unified Check-Run User manual (flutter/flutter#186210) 2026-05-08 [email protected] Roll Skia from 5f7adf4403d6 to a00db8749edb (1 revision) (flutter/flutter#186257) 2026-05-08 [email protected] Roll Packages from 0411f1d to 92552b1 (1 revision) (flutter/flutter#186256) 2026-05-08 [email protected] Add logging to figure out jvm crashes for `hot_mode_tests` (flutter/flutter#186107) 2026-05-08 [email protected] Roll Skia from 926c09741ce2 to 5f7adf4403d6 (3 revisions) (flutter/flutter#186242) ...
glTexSubImage2Dinto a mip level not previously defined byglTexImage2DraisesGL_INVALID_OPERATION. Both the lazy slice-init inBlitCopyBufferToTextureCommandGLES::EncodeandTextureGLES::InitializeContentsIfNecessaryonly ever allocated level 0, so any non-zero mip upload aborted with a fatal GL error. The pre-existing cubemap path inInitializeContentsIfNecessarywas also broken: it would re-bind aGL_TEXTURE_CUBE_MAPhandle toGL_TEXTURE_2Dand callglTexImage2Don the wrong target, a latent crash on the first cubemap sampler bind without a prior face upload.#185890 depends on this PR.
Approach
Per-
(slice, mip_level)initialization tracking with lazy allocation on first write:slices_initialized_becomesstd::array<std::bitset<16>, 6>(six cubemap faces by up to 16 mip levels, covering a 32k base dimension).InitializeContentsIfNecessaryallocates only the base mip level. This is byte-identical to pre-fix behavior on the 2D path, so Impeller's snapshot pipeline (Picture.toImage(generate_mips: true)->RenderTargetAllocator::CreateOffscreen[MSAA]-> render at level 0 ->glGenerateMipmap) keeps its existing GL footprint. For cubemaps the function now correctly bindsGL_TEXTURE_CUBE_MAPand allocates the base level for each of the six face targets.BlitCopyBufferToTextureCommandGLES::Encodeallocates the requested(slice, mip_level)lazily beforeglTexSubImage2D. Per-level uploads pay only for the levels they touch, and writes to a level afterglGenerateMipmap(orMarkContentsInitializedfrom the Android external-texture path) are skipped because those bits are already set.OnSetContents(the legacy upload path) is updated to use the new bit-marking API. Side-effect fix: the oldslices_initialized_ = AddOperation(...)assignment clobbered all six cubemap bits on every upload; the new API marks only the face that was actually written.Behavior table
TexImage2Dgenerate_mips=trueTexImage2Dupfront +glGenerateMipmapdriven implicit allocationsGL_INVALID_OPERATIONonglTexSubImage2D)TexImage2Dper mip on first writeBind()before any uploadGL_TEXTURE_2Dof cube handle)GL_TEXTURE_CUBE_MAPand allocate face base levelThis PR does not have a dedicated issue: it is a prerequisite bug fix for the per-
(mip, slice)upload path required by #185890, and the failure modes (GL_INVALID_OPERATIONonglTexSubImage2D, cubemap rebind to wrong target) are documented above. Verified via newBlitCommandGLESunit tests covering base-level, non-zero-mip, repeated-upload, every-mip-on-first-write, and cubemap face cases (MockGLESwiresglTexImage2DandglBindTextureto the existingMOCK_METHODdeclarations); the full GLES test suite passes locally (749 tests); manually confirmed withflutter_tester_opengles --enable-flutter-gpuagainstgpu_test.dartfrom #185890 thatTexture.overwrite writes to a non-zero mip leveland the cubemap-face tests pass.Pre-launch Checklist
///).