Writing a component plugin

This page will explain how to add a layout-level component: something drawn once per figure rather than once per trace, like a watermark, a custom legend, or a brush.

Planned topics:

• The component contract: name, layoutSchema, supplyLayoutDefaults, draw, pushMargin, and onInteraction
• Adding layout attributes that validate and appear in the generated reference
• Reserving margin space
• Handling pointer input
• Lifecycle hooks (beforePlot, afterPlot, beforerender, afterrender, destroy)
• A worked example: a watermark component