This sample demonstrates a diagram with rulers at its edges and indicators which display the mouse's position.

The rulers are implemented using Graduated Panels. The main element of each panel is sized according to the width/height of the viewport, with the Panel.graduatedMin and Panel.graduatedMax being set to the edges of the viewport.

Event listeners and Tool overrides are used to keep the rulers and indicators in sync as the viewport bounds change or the mouse moves around the diagram.

The rulers depend on the Diagram.viewportBounds, which can be impacted by changes to the Diagram.documentBounds. Therefore, the Part.isInDocumentBounds property is set to false to prevent circular dependencies in cases where the rulers grow/shrink to fit the viewport.