unity-editor-imgui-design

Custom Inspectors in Unity Editor IMGUI are created by extending Editor classes and implementing OnGUI methods to design property layouts. Use EditorGUILayout for automatic spacing, EditorGUI for low-level control, and the CustomEditor attribute to bind your Inspector to a specific component type, enabling multi-object editing and undo support within editor workflows.

EditorWindow creates panels and tools that run only in the Unity Editor using IMGUI and UnityEditor APIs, while in-game UI uses Canvas and uGUI for runtime gameplay. Editor IMGUI is designed for developer tools, asset management, and custom inspectors—not player-facing interfaces—and operates through editor-only lifecycle events like OnGUI and Repaint.

Unity Editor IMGUI uses Layout and Repaint event types within OnGUI callbacks to manage rendering efficiency. Layout events calculate control sizes and positions, while Repaint events draw the interface. Proper handling prevents layout exceptions and ensures responsive editor tools; use EditorGUILayout for automatic layout or manual Rect calculations for custom control placement.

Yes, Unity Editor IMGUI supports undo/redo through Undo.RecordObject and EditorUtility.SetDirty for asset modifications. Wrap property changes in Undo.BeginChangeCheck and Undo.EndChangeCheck blocks to track changes, enabling users to undo editor tool actions and maintain safe, predictable editor workflows for custom inspectors and property drawers.

Property Drawers customize how individual serialized fields render in the Inspector using IMGUI. Use them to create specialized controls for specific field types, add validation, or combine multiple properties into a single visual unit. They integrate seamlessly with EditorGUI and support both custom classes and built-in types, extending inspector functionality without full custom Inspector classes.