donner::editor::LayersPanel Class Reference

ImGui Layers panel backed by a LayerTreeModel snapshot. More...

#include "donner/editor/LayersPanel.h"

Classes
struct	ThumbnailTexture
	Maps a per-row rendered thumbnail bitmap to an ImGui texture handle for display. The editor shell supplies an implementation backed by GlTextureCache (the same Donner-bitmap -> GL/WGPU texture path the render pane uses); when null (e.g. in headless unit tests) the panel falls back to the deterministic swatch. Donner renders the thumbnail pixels; ImGui only blits the resulting texture - see CLAUDE.md "No Rendering Vector Graphics With ImGui". More...
struct	IconTexture
	Maps a static layer-affordance icon bitmap to an ImGui texture handle for display. The icon bitmaps are rendered from embedded Bootstrap SVG resources through Donner; ImGui only receives the final raster texture for the image button. More...
struct	ThumbnailRefreshStats
	Diagnostics for the most recent thumbnail refresh. More...
struct	ClickModifiers
	Modifier state for a row click. Mirrors the ImGui click path so tests can drive selection without a live ImGui frame. More...

Public Types
enum class	ThumbnailRefreshMode {   Render ,   SwatchesOnly }
using	ThumbnailTextureProvider
using	IconTextureProvider

Public Member Functions
void	refreshSnapshot (const EditorApp &app, svg::RendererInterface *renderer=nullptr, ThumbnailRefreshMode mode=ThumbnailRefreshMode::Render)
	Rebuild the row snapshot, per-row preview swatches, and per-row rendered thumbnail bitmaps from live editor state. Safe to call only when the async renderer is idle (delegates to LayerTreeModel::refresh and renders each row's element subtree through svg::Renderer::renderElementToBitmap, which takes document write access).
void	render (EditorApp *liveApp, const ThumbnailTextureProvider &textureProvider={}, const IconTextureProvider &iconTextureProvider={}, float minimumInteractionHeight=0.0f)
	Render the panel into the current ImGui window. Must be called inside an ImGui::Begin(...) / End() pair. When liveApp is null (the worker owns the document) mutating clicks are dropped.
void	setLockedRejectionFlash (std::optional< LayersLockedRejectionFlash > flash)
	Set the current locked-rejection flash (or clear it with std::nullopt). When set with a positive intensity and the flashed element matches a visible row, render paints that row's background red with alpha scaled by intensity, in sync with the canvas outline flash. EditorShell calls this each frame with SelectTool::lockedRejectionFlash() mapped into the input struct, before render.
std::optional< std::size_t >	flashedRowIndex () const
	The visible row index that the active locked-rejection flash maps to (an exact element match against a visible row), or std::nullopt when no flash is active, its intensity is non-positive, or its element is not a visible row. The non-ImGui seam the row-flash test asserts on.
float	lockedRejectionFlashIntensity () const
	The fade intensity of the active locked-rejection flash, or 0 when none is set. Testing/diagnostics accessor paired with flashedRowIndex.
const std::vector< LayerTreeRow > &	rows () const
	The current flat row list (testing/diagnostics accessor).
const ThumbnailRefreshStats &	thumbnailRefreshStats () const
	Diagnostics for the most recent thumbnail refresh.
std::size_t	visibleRowCount () const
	Number of currently-visible rows (rows in the flat list).
void	handleRowClick (EditorApp &app, std::size_t rowIndex, ClickModifiers mods)
	Apply the selection logic for a click on the visible row at rowIndex. This is the exact logic the ImGui click path uses, factored out so it is unit-testable without an ImGui context.
void	handleEyeClick (EditorApp &app, std::size_t rowIndex)
	Toggle the visibility of the row at rowIndex via the shared EditorApp::setElementVisible path (the same path the context-menu Hide/Show items use). Factored out so the eye-button affordance is unit-testable without an ImGui frame. No-op for an out-of-range index.
void	handleLockClick (EditorApp &app, std::size_t rowIndex)
	Toggle the lock state of the row at rowIndex via the shared EditorApp::setElementLocked path (the same path the context-menu Lock/Unlock items use). Factored out so the lock-button affordance is unit-testable without an ImGui frame. No-op for an out-of-range index.
bool	handleRowRename (EditorApp &app, std::size_t rowIndex, std::string_view newId)
	Rename the element at rowIndex to newId via the shared EditorApp::renameSelectedElement path - a DOM-level id change that also repoints url(#...) / href references and <style> selectors. The row's element is selected first (renaming the thing you double-clicked), then the engine runs. Factored out so the inline-edit affordance is unit-testable without an ImGui frame.
bool	handleRowReorder (EditorApp &app, std::size_t fromIndex, std::size_t toIndex)
	Move the element at fromIndex so it sits at the toIndex row's position, among the same parent's children, via the shared EditorApp::reorderElementBeforeSibling DOM move. Cross-parent drops and locked elements are rejected. Factored out so drag-to-reorder is unit-testable without an ImGui frame.
bool	handleRowZOrder (EditorApp &app, std::size_t rowIndex, EditorApp::ZOrder direction)
	Reorder the element at rowIndex in paint order (z-order) via the shared EditorApp::reorderSelectedElement engine - the same path as the canvas Arrange menu and the Cmd+[ / Cmd+] shortcuts. The row's element is selected first, then the move runs. Factored out so the Layers context-menu Arrange items are unit-testable without an ImGui frame.
void	beginRename (std::uint64_t stableId)
	Begin an inline rename of the row identified by stableId (the render loop draws an edit field in place of the row label). No-op if the row is not present. Exposed so the context-menu "Rename" item and tests can start an edit; the double-click path calls it internally.
std::optional< std::uint64_t >	renamingStableId () const
	The stable id of the row currently being inline-renamed, or std::nullopt.
bool	hasThumbnailOrSwatch (std::uint64_t stableId) const
	Whether the row identified by stableId has a non-null thumbnail handle or a deterministic fallback swatch. Always true for every visible row.
std::optional< css::RGBA >	rowFallbackSwatch (std::uint64_t stableId) const
	The fallback preview swatch color for the row identified by stableId, or std::nullopt if the row is not present.
const svg::RendererBitmap *	rowThumbnail (std::uint64_t stableId) const
	The Donner-rendered preview thumbnail bitmap for the row identified by stableId, or nullptr when the row has no real raster preview (it then uses the fallback swatch). This is the non-ImGui data seam: tests assert on the rendered pixels here without needing a GL context or an ImGui frame.
bool	consumeSelectionChanged ()
	Whether the most recent render / handleRowClick changed the editor selection. Consumes the flag. Used by EditorShell to fire the existing canvas/source selection-sync plumbing when a Layers row drives selection.
bool	consumeQueuedMutation ()
	Whether the most recent render queued a DOM mutation (show/hide, lock, rename, reorder, z-order) that is not reflected by a selection change. Consumes the flag. EditorShell flushes the queued mutation and re-renders when this is set; without it a show/hide toggle would leave the canvas showing the pre-mutation frame (the "hidden layer ghost" report).
void	noteRowHovered (std::optional< std::size_t > rowIndex)
	Record which visible row (if any) is under the mouse cursor. Called from render with the hovered row index, and directly by tests. Drives the canvas hover-highlight chrome the same way the source pane does. Passing std::nullopt (or an out-of-range index) clears the hover.
std::optional< svg::SVGElement >	hoveredElement () const
	The element under the mouse cursor as of the most recent render / noteRowHovered, or std::nullopt when no row is hovered.
const LayerTreeModel &	model () const
	Access the underlying model (testing/diagnostics).

Detailed Description

ImGui Layers panel backed by a LayerTreeModel snapshot.

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Class Documentation

donner::editor::LayersPanel::ThumbnailTexture

struct donner::editor::LayersPanel::ThumbnailTexture

Maps a per-row rendered thumbnail bitmap to an ImGui texture handle for display. The editor shell supplies an implementation backed by GlTextureCache (the same Donner-bitmap -> GL/WGPU texture path the render pane uses); when null (e.g. in headless unit tests) the panel falls back to the deterministic swatch. Donner renders the thumbnail pixels; ImGui only blits the resulting texture - see CLAUDE.md "No Rendering Vector Graphics With ImGui".

Parameters

stableId	Stable id of the row whose thumbnail is being uploaded.
bitmap	The Donner-rendered RGBA thumbnail bitmap.

Returns

An ImGui texture handle plus the valid payload UV range, or an empty texture if upload failed.

Class Members
ImTextureID	texture = 0	ImGui texture handle.
Vector2d	uvBottomRight = Vector2d(1.0, 1.0)	Bottom-right valid payload UV.

donner::editor::LayersPanel::IconTexture

struct donner::editor::LayersPanel::IconTexture

Maps a static layer-affordance icon bitmap to an ImGui texture handle for display. The icon bitmaps are rendered from embedded Bootstrap SVG resources through Donner; ImGui only receives the final raster texture for the image button.

Parameters

stableId	Stable id of the static icon resource being uploaded.
bitmap	The Donner-rendered RGBA icon bitmap.

Returns

An ImGui texture handle plus the valid payload UV range, or an empty texture if upload failed.

Class Members
ImTextureID	texture = 0	ImGui texture handle.
Vector2d	uvBottomRight = Vector2d(1.0, 1.0)	Bottom-right valid payload UV.

donner::editor::LayersPanel::ThumbnailRefreshStats

struct donner::editor::LayersPanel::ThumbnailRefreshStats

Diagnostics for the most recent thumbnail refresh.

Class Members
uint64_t	documentFrameVersion = 0	Document frame version observed during the refresh.
size_t	renderedCount = 0	Number of row thumbnails rasterized through Donner during this refresh.
double	renderMs = 0.0	Wall time spent in thumbnail rasterization work.
size_t	reusedCount = 0	Number of cached row thumbnails reused during this refresh.
size_t	rowCount = 0	Visible row count after refreshing the model.
size_t	skippedForCanvasInvalidationCount = 0	Number of rows skipped because the canvas render tree had pending invalidation.

donner::editor::LayersPanel::ClickModifiers

struct donner::editor::LayersPanel::ClickModifiers

Modifier state for a row click. Mirrors the ImGui click path so tests can drive selection without a live ImGui frame.

Class Members
bool	ctrl = false	Ctrl/Cmd toggles the clicked row in the selection.
bool	shift = false	Shift extends selection in visible row order.

Member Typedef Documentation

IconTextureProvider

using donner::editor::LayersPanel::IconTextureProvider

Initial value:

 
      std::function<IconTexture(std::uint64_t stableId, const svg::RendererBitmap& bitmap)>

ThumbnailTextureProvider

using donner::editor::LayersPanel::ThumbnailTextureProvider

Initial value:

 
      std::function<ThumbnailTexture(std::uint64_t stableId, const svg::RendererBitmap& bitmap)>

Member Function Documentation

handleEyeClick()

void donner::editor::LayersPanel::handleEyeClick	(	EditorApp &	app,
		std::size_t	rowIndex )

Toggle the visibility of the row at rowIndex via the shared EditorApp::setElementVisible path (the same path the context-menu Hide/Show items use). Factored out so the eye-button affordance is unit-testable without an ImGui frame. No-op for an out-of-range index.

Parameters

app	Live editor app the mutation is applied to.
rowIndex	Index into rows().

handleLockClick()

void donner::editor::LayersPanel::handleLockClick	(	EditorApp &	app,
		std::size_t	rowIndex )

Toggle the lock state of the row at rowIndex via the shared EditorApp::setElementLocked path (the same path the context-menu Lock/Unlock items use). Factored out so the lock-button affordance is unit-testable without an ImGui frame. No-op for an out-of-range index.

Parameters

app	Live editor app the mutation is applied to.
rowIndex	Index into rows().

handleRowClick()

void donner::editor::LayersPanel::handleRowClick	(	EditorApp &	app,
		std::size_t	rowIndex,
		ClickModifiers	mods )

Apply the selection logic for a click on the visible row at rowIndex. This is the exact logic the ImGui click path uses, factored out so it is unit-testable without an ImGui context.

Parameters

app	Live editor app the selection request is applied to.
rowIndex	Index into rows().
mods	Modifier-key state for the click.

handleRowRename()

bool donner::editor::LayersPanel::handleRowRename	(	EditorApp &	app,
		std::size_t	rowIndex,
		std::string_view	newId )

Rename the element at rowIndex to newId via the shared EditorApp::renameSelectedElement path - a DOM-level id change that also repoints url(#...) / href references and <style> selectors. The row's element is selected first (renaming the thing you double-clicked), then the engine runs. Factored out so the inline-edit affordance is unit-testable without an ImGui frame.

Parameters

app	Live editor app the mutation is applied to.
rowIndex	Index into rows().
newId	The requested new element id.

Returns

True if the rename was applied; false on out-of-range index or when the engine rejects it (locked, empty, unchanged, or duplicate id).

handleRowReorder()

bool donner::editor::LayersPanel::handleRowReorder	(	EditorApp &	app,
		std::size_t	fromIndex,
		std::size_t	toIndex )

Move the element at fromIndex so it sits at the toIndex row's position, among the same parent's children, via the shared EditorApp::reorderElementBeforeSibling DOM move. Cross-parent drops and locked elements are rejected. Factored out so drag-to-reorder is unit-testable without an ImGui frame.

Parameters

app	Live editor app the mutation is applied to.
fromIndex	Index of the dragged row.
toIndex	Index of the drop-target row.

Returns

True if a move was applied; false on out-of-range/no-op/rejected.

handleRowZOrder()

bool donner::editor::LayersPanel::handleRowZOrder	(	EditorApp &	app,
		std::size_t	rowIndex,
		EditorApp::ZOrder	direction )

Reorder the element at rowIndex in paint order (z-order) via the shared EditorApp::reorderSelectedElement engine - the same path as the canvas Arrange menu and the Cmd+[ / Cmd+] shortcuts. The row's element is selected first, then the move runs. Factored out so the Layers context-menu Arrange items are unit-testable without an ImGui frame.

Parameters

app	Live editor app the mutation is applied to.
rowIndex	Index into rows().
direction	Which way to move the element in paint order.

Returns

True if the element moved; false on out-of-range index or when the engine rejects it (root element, locked, or already at the extreme).

refreshSnapshot()

void donner::editor::LayersPanel::refreshSnapshot	(	const EditorApp &	app,
		svg::RendererInterface *	renderer = nullptr,
		ThumbnailRefreshMode	mode = ThumbnailRefreshMode::Render )

Rebuild the row snapshot, per-row preview swatches, and per-row rendered thumbnail bitmaps from live editor state. Safe to call only when the async renderer is idle (delegates to LayerTreeModel::refresh and renders each row's element subtree through svg::Renderer::renderElementToBitmap, which takes document write access).

Parameters

app	Live editor app to snapshot.
renderer	Optional renderer to use for thumbnail rasterization.
mode	Whether to render thumbnails or refresh only the row swatches.

render()

void donner::editor::LayersPanel::render	(	EditorApp *	liveApp,
		const ThumbnailTextureProvider &	textureProvider = {},
		const IconTextureProvider &	iconTextureProvider = {},
		float	minimumInteractionHeight = 0.0f )

Render the panel into the current ImGui window. Must be called inside an ImGui::Begin(...) / End() pair. When liveApp is null (the worker owns the document) mutating clicks are dropped.

Parameters

liveApp	Live editor app for selection/mutation, or null.
textureProvider	Uploads a row's rendered thumbnail bitmap to an ImGui texture for display, or null to fall back to the swatch.
iconTextureProvider	Uploads the static Donner-rendered layer icon bitmaps to ImGui textures for display, or null to keep a blank hit area in headless tests.
minimumInteractionHeight	Minimum row and icon-button target height. Compact touch sheets pass 44 logical pixels; desktop keeps the dense default by passing zero.

rowThumbnail()

const svg::RendererBitmap * donner::editor::LayersPanel::rowThumbnail ( std::uint64_t stableId ) const

nodiscard

The Donner-rendered preview thumbnail bitmap for the row identified by stableId, or nullptr when the row has no real raster preview (it then uses the fallback swatch). This is the non-ImGui data seam: tests assert on the rendered pixels here without needing a GL context or an ImGui frame.

Parameters

stableId

Stable id of the row.

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

• donner/editor/LayersPanel.h