Overlays are used to render objects in 2D screen-space on top of a 3D scene. For example, overlays can be used to display your company's logo, create a heads-up display (HUD), or create a translucent user interface. The texture overlay can render static images, such as a company logo or a UI button, or dynamic images, such as a video feed from a UAV. The panel overlay is used to form hierarchies of overlays, which is useful for creating UI elements, such as toolbars. All overlays support pixel and fractional units, translation, scale, and rotation transformations, and a user defined z-order.
Overlays are in the AGI.Graphics.Overlays namespace. Insight3D provides the following overlays:
| Topic | Description |
|---|---|
| Texture | This topic introduces the texture overlay and basic concepts applicable to all overlays: pixel vs. fractional units, anchor style, transformations, z-order, and borders. |
| Panel | Panel overlays are used to create hierarchies of overlays. This is frequently used to create UIs. For example, to implement a toolbar, create one panel overlay and a texture overlay for each button. Add each texture overlay to the panel to create a parent-child relationship. |
| Picking | Picking allows users to select and interact with overlays on the screen, and can be used to create interactive UI elements. |