De-ImGui XCUI standalone text atlas provider

docs/plan/XCUI_Phase_Status_2026-04-05.md

@@ -16,7 +16,7 @@ Old `editor` replacement is explicitly out of scope for this phase.
   - `LayoutLab` continues as the editor widget proving ground for tree/list/property-section style controls
   - the demo sandbox and editor bridge APIs were tightened again without touching the old editor replacement scope
   - `new_editor` now has an explicit two-step window compositor seam through `IWindowUICompositor` / `ImGuiWindowUICompositor`, layered on top of `IEditorHostCompositor` / `ImGuiHostCompositor`
-- The native-host follow-up is now landed in `new_editor`:
+- The native-host / hosted-preview publication follow-up is now landed in `new_editor`:
   - `NativeWindowUICompositor` is now buildable alongside the legacy ImGui compositor
   - `Application` now defaults to a native XCUI host path instead of creating the ImGui shell by default
   - the native default path now drives `XCUIDemoRuntime` and `XCUILayoutLabRuntime` directly, composes their `UIDrawData`, and submits one swapchain packet through the native compositor
@@ -24,6 +24,9 @@ Old `editor` replacement is explicitly out of scope for this phase.
   - the native shell now begins the hosted-preview queue/registry lifecycle each frame, queues native preview frames, drains them during the native render pass, and consumes published hosted-surface images directly in panel cards with live/warming placeholder states
   - the old ImGui shell path remains present as an explicit compatibility host instead of the default host
   - `XCUIInputBridge.h` no longer drags `imgui.h` through the public XCUI input seam
+- The default native text path is now also de-ImGuiized inside `new_editor`:
+  - `XCUIStandaloneTextAtlasProvider` now builds and owns its atlas through a Windows/GDI raster path instead of using ImGui font-atlas internals
+  - the standalone atlas provider now exposes both `RGBA32` and `Alpha8` views, supports non-nominal size resolution, lazily adds non-prebaked BMP glyphs, and falls back to `?` when a glyph cannot be rasterized
 - Old `editor` replacement remains deferred; all active execution still stays inside XCUI shared code and `new_editor`.
 
 ## Three-Layer Status
@@ -50,7 +53,7 @@ Current gap:
 
 - Minimal schema self-definition support is landed, including consistency checks for enum/document-only schema metadata, but schema-driven validation for `.xcui` / `.xctheme` instances is still not implemented.
 - Shared widget/runtime instantiation is still thin and mostly editor-side.
-- Common widget primitives are still incomplete: shared text-input presentation/composition on top of the new text controller, multi-selection/focus-traversal/virtualized collection state on top of the new editor-primitive helpers, and a fully native text/font-atlas path that no longer leans on ImGui font internals.
+- Common widget primitives are still incomplete: shared text-input presentation/composition on top of the new text controller, multi-selection/focus-traversal/virtualized collection state on top of the new editor-primitive helpers, shared scroll/navigation-scope/caret-layout helpers, and promotion of the current native text-atlas path into a shared/cross-platform text subsystem.
 
 ### 2. Runtime/Game Layer
 
@@ -118,9 +121,10 @@ Current gap:
 Current gap:
 
 - The default shell host is now native, but the legacy ImGui shell and panel path still exists as a compatibility host and is still compiled into `new_editor`.
+- The default native shell path is still compiled through an `Application` translation unit that directly includes legacy ImGui host/presenter/compositor code, and `new_editor/CMakeLists.txt` still treats those legacy ImGui sources and include paths as target-global defaults.
 - The native shell currently proves direct runtime composition, but its shell chrome is still a bespoke `Application`-side layout rather than a fully shared XCUI-authored editor shell document.
 - Editor-specialized widgets are still incomplete at the shared-module level: the authored prototypes exist, but virtualization, multi-selection/focus traversal, toolbar/menu chrome, menu interaction widgets, and icon-atlas widgets are not yet extracted into reusable XCUI modules.
-- The default native path still depends on ImGui font-atlas internals through `XCUIStandaloneTextAtlasProvider`, so text rendering is not yet cleanly de-ImGuiized even though the shell/panel composition path is native by default.
+- The default native text path now uses a standalone Windows/GDI atlas through `XCUIStandaloneTextAtlasProvider`, but that provider still lives inside `new_editor` and is not yet promoted into a shared/cross-platform text subsystem.
 
 ## Validated This Phase
 
@@ -131,17 +135,19 @@ Current gap:
 - `new_editor_xcui_layout_lab_runtime_tests`: `12/12`
 - `new_editor_xcui_rhi_command_compiler_tests`: `7/7`
 - `new_editor_xcui_rhi_render_backend_tests`: `5/5`
+- `new_editor_xcui_standalone_text_atlas_provider_tests`: `6/6`
 - `new_editor_xcui_hosted_preview_presenter_tests`: `20/20`
 - `new_editor_imgui_window_ui_compositor_tests`: `7/7`
 - `new_editor_native_window_ui_compositor_tests`: `8/8`
 - `new_editor_xcui_editor_command_router_tests`: `5/5`
-- `new_editor_application_shell_command_bindings_tests`: `8/8`
+- `new_editor_application_shell_command_bindings_tests`: `11/11`
 - `new_editor_xcui_shell_chrome_state_tests`: `11/11`
 - `new_editor_xcui_panel_canvas_host_tests`: `4/4`
 - `new_editor_imgui_xcui_panel_canvas_host_tests`: `1/1`
 - `new_editor_native_xcui_panel_canvas_host_tests`: `4/4`
 - `new_editor_xcui_layout_lab_panel_tests`: `3/3`
 - `XCNewEditor` Debug target builds successfully
+- `XCNewEditor.exe` native-default smoke run stayed alive for `5s`
 - `core_ui_tests`: `52 total` (`50` passed, `2` skipped because `KeyCode::Delete` currently aliases `Backspace`)
 - `scene_tests`: `68/68`
 - `core_ui_style_tests`: `5/5`
@@ -253,7 +259,7 @@ Current gap:
   - generic preview frame submission no longer carries an ImGui draw-list pointer
   - the ImGui presenter now resolves inline draw targets through an explicit ImGui-only binding seam
   - panel/runtime callers still preserve the same legacy and native-preview behavior
-- Native hosted-preview publication is now wired through the default shell path:
+- Native hosted-preview publication milestone is now wired through the default shell path:
   - `NativeWindowUICompositor` publishes hosted preview textures as SRV-backed XCUI registrations and frees them through the compositor seam
   - `Application::BeginHostedPreviewFrameLifecycle(...)` now resets queue/registry state for both legacy and native frame paths
   - hosted-preview surface readiness now keys on published texture availability instead of ImGui-style descriptor validity
@@ -266,19 +272,38 @@ Current gap:
 - XCUI asset document loading changed to prefer direct source compilation before `ResourceManager` fallback for the sandbox path, fixing the LayoutLab crash.
 - `UIDocumentCompiler.cpp` repaired enough to restore full local builds after the duplicated schema-helper regression.
 - MSVC debug build hardening was tightened again so large parallel `engine` rebuilds stop tripping over compile-PDB contention.
+- `XCUIStandaloneTextAtlasProvider` no longer uses ImGui font-atlas/internal baking helpers:
+  - atlas ownership now stays inside a standalone provider implementation built on Windows/GDI glyph rasterization
+  - default editor atlas prewarms the current supported nominal sizes, exposes both `RGBA32` and `Alpha8` atlas views, lazily inserts non-prebaked BMP glyphs, and falls back to `?` for unrasterizable codepoints
+  - standalone atlas coverage now includes reset/rebuild, non-nominal size resolution, lazy glyph insertion/fallback behavior, and smoke use without any ImGui context
 
 ## Phase Risks Still Open
 
 - Schema instance validation is still open beyond `.xcschema` self-definition and artifact round-trip coverage.
 - `ScrollView` is still authored/static; no wheel-driven scrolling or virtualization yet.
-- The default native text path still builds its font atlas on top of ImGui font types/internal baking helpers.
+- The default native shell path still compiles through an `Application.cpp` unit that directly pulls in ImGui compatibility host code, so the native default path is not yet isolated at the translation-unit boundary.
+- `new_editor/CMakeLists.txt` still builds the legacy ImGui host/compositor/backend sources and include directories as target-global defaults instead of a compatibility-only slice.
+- The default native text path now owns its atlas without ImGui, but the provider is still Windows-only and remains trapped inside `new_editor` instead of a shared/cross-platform text layer.
 - Hosted-preview compatibility presentation still depends on an ImGui-only inline presenter path when not using the queued native surface path.
 - Editor widget coverage is still prototype-driven inside `LayoutLab`; it has not yet been promoted into a full reusable shared widget/runtime layer with command routing, virtualization, and property-edit transactions.
 
+## Execution-Plan Alignment
+
+- Against `XCUI完整架构设计与执行计划.md`, current `new_editor` progress should be treated as an early `Phase 8` foothold rather than full `Milestone E` completion:
+  - landed: `NativeWindowUICompositor`, native shell packet composition, native hosted-preview publication, XCUI-owned texture registrations, native panel surface-image presentation, standalone native text-atlas ownership inside `new_editor`
+  - not yet landed: default-path translation-unit isolation from legacy ImGui host code, promotion of the native text-atlas path into a shared/cross-platform text subsystem, shared XCUI-authored editor shell chrome
+- That means the next de-ImGui push should not keep centering on hosted-preview publication; that milestone is now effectively closed for the default native shell path.
+- The real remaining default-path blockers are:
+  - isolate legacy ImGui shell/compositor/presenter wiring from the default `Application` build path
+  - stop treating ImGui include paths and backend sources as the default `new_editor` compilation surface
+  - harden and promote `XCUIStandaloneTextAtlasProvider` / editor font bootstrap into a shared native text subsystem
+  - move native shell chrome out of bespoke `Application` layout code and into a shared XCUI shell model or authored shell document
+
 ## Next Phase
 
 1. Expand runtime/game-layer ownership from the current `SceneRuntime` UI context into scene-declared HUD/menu bootstrapping, draw submission, and higher-level runtime UI policies.
 2. Promote the current editor-facing widget prototypes out of authored `LayoutLab` content and into reusable XCUI widget/runtime modules, then continue with toolbar/menu chrome, shell-state adoption, virtualization, and broader focus/multi-selection behavior.
-3. Strip the remaining default-path ImGui seams down to compatibility-only code, starting with the standalone text/font-atlas path and then the remaining hosted-preview fallback layers.
-4. Promote the native shell chrome and card layout out of bespoke `Application` code into a shared XCUI/editor-layer shell model or authored shell document.
-5. Continue phased validation, commit, push, and plan refresh after each stable batch.
+3. Isolate legacy ImGui shell/compositor/presenter wiring from the default native path first, starting with `Application` translation-unit separation and a `new_editor` build split that stops treating ImGui include paths and sources as the default compilation surface.
+4. Promote the current standalone native text/font path out of `new_editor`, harden its atlas invalidation/caching contract, and remove the remaining default-path ImGui text/bootstrap ownership around compatibility-only code.
+5. Promote the native shell chrome and card layout out of bespoke `Application` code into a shared XCUI/editor-layer shell model or authored shell document.
+6. Continue phased validation, commit, push, and plan refresh after each stable batch.