Process a window event. Returns true on redraw request.

Ramer-Douglas-Peucker line simplification with pressure preservation.

Read an embedded label (quoted or bare) at `start`, returning the trimmed label text and the index just past it. A bare label stops at a connector cha

Read a `|...|` label starting at the opening pipe. Returns the label and the index past the closing pipe.

Remove a shape, syncing to CRDT if enabled.

Render angle snap visualization (polar rays and angle arc).

Render a small text badge (background rect + white text).

Render the bottom-left toolbar with grid toggle and zoom controls.

Render the collaboration modal dialog.

Render eraser cursor (circle showing eraser radius).

Render the hamburger menu and collab button at top-left.

Render a freehand shape with variable width based on pressure.

Render grid as small crosses (+) at intersections. Uses batched paths for performance.

Render grid as dots at intersections. Uses batched rectangles for performance.

Render a single handle. Stroke widths are scaled inversely with zoom to maintain constant screen size.

Render an image shape.

Render laser pointer with trail.

Render a math (LaTeX) shape using ReX.

Render the math equation editor dialog.

Render the open dialog modal with dropdown.

Render the open recent dialog modal.

Render the presence panel showing connected users.

Render the properties panel at the top.

Render the right-side properties panel for selected shapes.

Render rotation helper lines (center crosshair and angle indicator).

Render the save dialog modal.

Render a selection rectangle (marquee). Stroke width and dash pattern are scaled inversely with zoom.

Render shape-specific selection handles. Handles are scaled inversely with zoom to maintain constant screen size.

Render the keyboard shortcuts modal.

Render smart guide lines (magenta alignment guides like Figma).

Render snap guides (crosshairs at the snap point).

Render the tab strip (top-center) with one button per open canvas plus a control to load an Excalidraw library as a new tab. Icons in a library tab ar

Render a text shape using Parley for proper text layout.

Render a text shape in edit mode using PlainEditor state. This renders the text with cursor and selection highlights.

Render the toolbar and return any triggered action.

Render all UI and return any triggered action.

Print a human-readable report and return the process exit code.

Request clipboard text read (async). Result will be available via take_pending_clipboard_text().

Request clipboard text for math editor (async).

Generate only a rotation handle (no corner resize handles).

Secondary button (gray background, gray text).

Test if two line segments (a-b) and (c-d) intersect.

Get the current selection range as byte offsets. Returns None if selection is collapsed (just a cursor).

Get the current selection rectangle (for rendering).

Send a shape to the back (bottom of z-order).

Set the text brush color.

Set the font size.

Set the document name.

Setup drag-drop handlers on the canvas element. Call this once after the canvas is created.

Identify a shape bracket opening at `i`, returning `(open, close, shape)`. Two-character delimiters are tested before single-character ones.

Find shapes that intersect or are contained within a rectangle.

Set keyboard shortcut (shown in hover tooltip).

Check if enough time has passed for an auto-save.

Create a small icon button style (24x24 button, 16x16 icon) for bottom toolbar

Snap a point along an angle ray to smart guides. Returns the intersection of the ray with the nearest aligned shape edge.

Get the state of a shape.

Call at the start of each frame.

Get a reference to the storage backend.

Remove a surrounding Markdown code fence (```mermaid ... ```), if present, and return the inner diagram text. Leaves un-fenced input untouched.

Strip a trailing Mermaid `%% ...` comment.

Strip a trailing Mermaid `%% ...` comment from a line.

Switch the active tab, preserving the outgoing tab's edits.

Take pending clipboard text if available.

Take pending document from async load operation.

Take the pending document list.

Take any pending dropped document JSON.

Take all pending dropped images.

Take pending Excalidraw shapes from clipboard paste.

Take the pending image from clipboard paste.

Take a pending library `(name, document)` from an async load.

Take pending math clipboard text if available.

Take ownership of the scene (resets internal scene).

Create a toolbar tool button style (32x32, solid blue when selected)

Get number of active touches.

Try to interpret text at `label_start` as an embedded link label that is followed by a closing connector run. Returns the completed link on success.

Try to load the last document on startup.

Ungroup the currently selected groups. Returns the IDs of all ungrouped children.

Ungroup a group shape, returning its children to the document. Returns the IDs of the ungrouped children, or None if the shape is not a group.

Update UI state from a shape's style.

Update laser trail (fade out old points). Call each frame.

Upload document from file input - triggers async file picker. Use `take_pending_document()` to retrieve the loaded document.

Get the current version vector.

Get the visible world bounds (viewport in world coordinates).

Set the angle snap info for rendering angle guides.

Set the background color.

Set the shape ID being edited (will be skipped in build_scene).

Set eraser cursor position and radius.

Set the grid style.