This example shows a fixed relation-graph canvas where users can marquee-select multiple existing nodes, clear selection with a canvas click, and switch canvas dragging between selection and move modes. It also surfaces live selection geometry and a selected-node count in a floating helper window, while reusing shared canvas settings and image export tooling.

Canvas Multi-Node Selection with Live Telemetry

What This Example Builds

This example builds a full-height graph viewer for selecting multiple existing nodes with a drag rectangle. Users see a centered icon-based network, a floating helper window, a mode toggle that switches canvas dragging between selection and move, and a live counter of how many nodes are currently selected. The main point is not graph editing, but turning relation-graph marquee selection into an explicit multi-node pi