# Positioning a Scene's Origin Within its View

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Try the different ways to configure the scene's origin inside its view.

### Overview

You use the scene's `anchorPoint` to orient the default screen position of its nodes. For example, setting the scene's anchorPoint to (0,0) makes child nodes with a position of (0,0) display at the bottom-left corner of the scene. However, setting the scene's anchorPoint to (0.5,0.5) makes child nodes with a position of (0,0) display in the center of the scene.
You only use the scene's anchorPoint for scene's that don't have a camera. If, however, you set a scene's camera, then the `camera` drives which portion of the scene is visible at any given time, and the anchorPoint is ignored.

### Set the Scene's Origin to the Bottom-Left of its View

By default, a scene’s origin is placed in the lower-left corner of the view, as shown in the figure below. A scene initialized with a height of 1024 and a width of 768 has the origin (0,0) in the lower-left corner, and the (1024,768) coordinate in the upper-right corner. The `frame` property holds (0,0)-(1024,768).

A scene’s `position` property is ignored by Scene Kit because the scene is always the root node for a node tree. Its default value is `zero` and you can’t change it. However, you can move the scene’s origin by setting its `anchorPoint` property. The anchor point is specified in the unit coordinate space and chooses a point in the enclosing view.


###### Figure 1 Default anchor for a scene is in the lower-left corner of the view

![positioning-a-scenes-origin-within-its-view-001](/images/004-skscene-positioning-a-scenes-origin-within-its-view-001.png)


The default value for the anchor point is `zero`, which places it at the lower-left corner. The scene’s visible coordinate space is (0,0) to (width,height). The default anchor point is most useful for games that do not scroll a scene’s content.

### Center the Scene's Origin Within its View

The second-most common anchor point value is (0.5,0.5), which centers the scene’s origin in the middle of the view as shown in the figure below. The scene’s visible coordinate space is (-width/2,-height/2) to (width/2,height/2). Centering the scene on its anchor point is most useful when you want to easily position nodes relative to the center of the screen, such as in a scrolling game. However, this effect is better achieved using a `SKCameraNode`.


###### Figure 2 Moving the anchor point to the center of the view

![positioning-a-scenes-origin-within-its-view-001](/images/004-skscene-positioning-a-scenes-origin-within-its-view-002.png)

As a result of setting the anchorPoint and size, you indirectly set the scene’s frame, which determines the portion of the scene that's visible to the user.

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