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World Effects
World Effects Overview

Introduction to World Effects

The effects that you can create in Spark AR Studio fall into 2 broad categories:

In this article, we introduce the different ways you can create world effects.

The plane tracker

A plane tracker helps you to create world effects by finding a horizontal surface in the real world, like a floor or table, for you to anchor your objects to.

Objects that are children of the plane tracker appear when a suitable surface is detected:

A parade of 3D cats is seen walking down a street.

This example (which you can learn how to build) shows a plane tracker being used to create the effect of a 3D object appearing from the ground:

A 3D hand appears from the tracked surface.

To get started, add a plane tracker to the Scene panel by selecting Add Object.

Alternatively, select a plane tracking effect template from the Spark AR Studio welcome screen. Object Reveal, 2D/3D Stickers and Real-Scale World Objects are just a few of the templates that make use of the plane tracker.

Once you’re confident with the basics, try experimenting with effects that:

The target tracker

Target tracking effects are triggered when the camera is pointed at a specific image in the real world, like a poster for a movie. There are 2 types of target trackers:

  • Moving — The effect moves with the target image if the target image changes position. The effect disappears if the camera isn’t pointing at the target.
  • Fixed — The effect appears where the camera first detected the target image. If the target leaves the camera's view, the effect is still displayed and tracked correctly.

This example (which you can learn how to build) shows a fixed target tracker being used. 3D objects appear when the camera detects the poster:

3D shapes appear when the target poster is detected.

The next example shows a moving target tracker. 3D objects appear when the target (a cookie) is detected. Those objects move as the target changes position:

3D shapes appear when the target is detected, and move as the target is repositioned.

To get started, add a target tracker to the Scene panel by selecting Add Object. Once you select the target tracker in the Scene panel, you can upload a target image and change tracking type from the Inspector:

Alternatively, select the target tracking effect template (3D Animated Poster) from the Spark AR Studio welcome screen.

Once you’re confident with the basics, try experimenting with effects that:

  • Track multiple targets.
  • Track multiple faces of the same object.
  • Track a large object, like a building or billboard.

Camera space VS world space

By default, all objects are added to the scene as children of the Camera in the Scene panel. This means they're in camera space, and move with the movement of the device.

To see camera space, select the Camera in the Scene panel. This highlights 2 rectangles in the Viewport in blue:

  • The smaller rectangle represents the mobile device.
  • The larger rectangle represents what's in view of the camera.

In the example below, the heart is in camera space:

The heart is fixed inside the frame of the camera.

When an object is no longer a child of the Camera, it's in world space. This means you can place an object in a fixed location in someone's environment and it won't move with the camera.

Moving between camera and world space

To move objects out of camera space and into world space:

  1. Select the object.
  2. Drag it to the bottom of the Scene panel.

This positions the object at 0 along the X, Y and Z axes:

The heart is outside the frame of the camera.

To move it back to camera space, drag the object back into position as a child of the Camera in the Scene panel.

To move objects in these 2 spaces, use the Manipulators at the top of the Viewport or edit the object’s Transformations values in the Inspector.

Removing the Device Motion capability

When you move an object into world space, the Device Motion capability is added. Leaving it in place limits the mobile devices your effect works on. So, it's a good idea to remove it if you decide to make an effect in camera space instead.

To remove the capability:

  1. Go to Project in the menu bar and select Edit Properties.
  2. Select Capabilities then Device Motion.
  3. Click the icon.
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