Object Properties

How do objects in the scene look and behave

Each object in your scene has properties that control its presentation and behaviour. As a minimum, this includes its position, rotation and scale but there are loads more that you can optionally add. These properties can be changed during the experience based upon interactions.

The available position for an object will be affected by your scene type. For a Table Top experience, all objects are positioned proportionally with x,y,z coordinates from (-0.5, 0, -0.5) to (0.5, 1, 0.5), and like a vector graphics, these positions will scale smoothly with the surface size. For Room type experiences, the position will be specified in meters and limited by the maximum size of the room specified in the scene settings.

0,0,0 represents the center of the scene, with the object resting on the surface/floor.

You can drag and drop objects on the scene canvas to reposition them or use the sliders in the Inspector, which are conveniently labelled from:

Rotation is between -180 and 180 degrees in all three axes. It can be controlled by three sliders in the Inspector.

Like positions, object size in wiarframe is based on scene type — proportional for Table Top experiences and in meters for Room Size. The maximum is either 1 (100%) of the scene size. There is an option to maintain aspect ratio when scaling.

Each object can be set to either visible or hidden. When visible, you can also control the opacity and render mode. The latter controls whether the object is drawn as just a wireframe outline, shaded in, or a combination of both.

You can enable or disable physics on an object. If enabled the object will participate in collisions with other physics-enabled objects, it will also be affected by gravity.

If the 3D model includes any animations, then these can be selected and played in the experience. You can also choose if these animations should play on loop.

If the movability property is enabled, then the end-user can drag the object across the surface/floor in the experience.

If the rotatability property is enabled then the end-user can use a two-finger rotate gesture to rotate the object around its Up-Axis, i.e. spin it around.

If the scalability property is enabled, then the end-user can use a two-finger pinch gesture to shrink or stretch the object. It will maintain aspect ratio when scaling.

You can move an object over time by applying velocity to it. This can either be relative to the scene direction or relative to the object’s individual direction. The latter option, can for example, be used to move a character in the direction it is facing.

Velocity is measured in units per second, either fractional 0–1 for Table Tops or meters for Rooms.

You can rotate an object over time by applying rotational velocity. It is measured in degrees per second.

You can shrink or grow an object over time by applying scale velocity. It is measured in multiplies per second, ranging from 0.1 to 2. Setting this value to 2 would double the size of the object every second. There is an option to maintain aspect ratio when scaling.

An object’s positioned can be bound to another object in the scene or the camera (i.e. the user). Whenever the other object or camera moves, the object will move with it, as if connected by an invisible link.

When connected to a camera you also have the option of staying in place or zooming in. Zooming in, will attach the object to the camera. When done with a 2D image, this will achieve a Screen Space or traditional UI look. You can also choose where on the screen it should be anchored too, and decided which dimensions should be used for scaling image — picking both dimensions may resort is aspect ratio distortion based on the screen size.

An object’s rotation can also be bound to another object in the scene or the camera. The object can either match the rotation of the other object or look towards the other object. When set to match, the object will adjust its rotation whenever the other object or camera rotates. When set to look at, the object will adjust its rotation whenever the other object or camera moves.

An object’s scale can also be bound to another object in the scene. The object will then match its scale to that of the other object.

3D objects have an additional property called style. Styles provide a convenient way to change the look of a 3D model based upon interactions. We preconfigure these styles through the asset manager — more on this later — and then change them in the properties inspector.

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