topics/screen-coordinates guide

Screen coordinates: projecting a world position to the screen (worldToScreen), the mouse cursor position and a touch, raycasting from a screen point through the camera (screenToRay, Physics.raycastScreen), and placing a HUD marker, a name tag, a health bar or an off-screen edge arrow over a 3D object. The scene viewport's physical pixels and the UI's logical points, and ui.fromViewport / ui.toViewport, the step between them.

Surfaced through guides { path: "topics/screen-coordinates" } and man topics/screen-coordinates. The content lives in guide.md.