Package	starling.display
Class	public class Sprite3D
Inheritance	Sprite3D DisplayObjectContainer DisplayObject EventDispatcher Object

A container that allows you to position objects in three-dimensional space.

Starling is, at its heart, a 2D engine. However, sometimes, simple 3D effects are useful for special effects, e.g. for screen transitions or to turn playing cards realistically. This class makes it possible to create such 3D effects.

Positioning objects in 3D

Just like a normal sprite, you can add and remove children to this container, which allows you to group several display objects together. In addition to that, Sprite3D adds some interesting properties:

• z - Moves the sprite closer to / further away from the camera.
• rotationX — Rotates the sprite around the x-axis.
• rotationY — Rotates the sprite around the y-axis.
• scaleZ - Scales the sprite along the z-axis.
• pivotZ - Moves the pivot point along the z-axis.

With the help of these properties, you can move a sprite and all its children in the 3D space. By nesting several Sprite3D containers, it's even possible to construct simple volumetric objects (like a cube).

Note that Starling does not make any z-tests: visibility is solely established by the order of the children, just as with 2D objects.

Setting up the camera

The camera settings are found directly on the stage. Modify the 'focalLength' or 'fieldOfView' properties to change the distance between stage and camera; use the 'projectionOffset' to move it to a different position.

Limitations

On rendering, each Sprite3D requires its own draw call — except if the object does not contain any 3D transformations ('z', 'rotationX/Y' and 'pivotZ' are zero). Furthermore, it interrupts the render cache, i.e. the cache cannot contain objects within different 3D coordinate systems. Flat contents within the Sprite3D will be cached, though.

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