Particle systems let you display and move large numbers of objects, called particles. You can apply force and drag to particles, to mimic the effects of gravity.
Use particle systems to produce all kinds of visual experiences - for example, rain, smoke and confetti.
You can also find out how to build a full effect using particle systems in this tutorial.
To add a particle system:
The particle system will be shown as emitter0 in the Scene Panel. You'll see a small stream of objects in the center of the Viewport.
When a particle system is selected in the Scene Panel, you'll be able to make changes to it by editing its properties in the Inspector:
In the Inspector, edit the values next to:
You can also use the Manipulators to do this.
The options to edit the emitter are listed under Emitter in the Inspector.
Editing Type will change the shape of the source the particles come from.
Use the dropdown next to Type to select either:
Select whether the particles appear in either:
Control the rate at which particles are emitted.
It's set to 20 particles per second by default. You can use the percentage option to add variation.
If the birthrate was changed to 70 and 40%, every second between 42 and 98 particles would be created.
Change the emitter's angle along the X, Y and Z axis. Edit the values in the second box to set the volume of emisson. For example, to create a cone shaped emission or scatter particles in all directions across the scene.
Change the speed the particles move at.
Check this box to start the particle system before the effect is opened. You can adjust when the particle system starts, in seconds.
The options to edit the particles themselves are listed under Particle in the Inspector.
Change the size of the particles
Set how long each particle will appear for in the effect. It's set to 0.4 seconds by default - so each particle is removed after it's been shown for 0.4 seconds.
Specify how fast particles will rotate around each axis during their lifetime.
Set how the particles rotate around each axis as they emit. To change particle rotation during their lifetime, set the Angular Velocity.
Checking this box means particles will always face the camera. You’ll then be able to edit the Spin and Tilt values.
Set an angle for particles to spin at. It's set to 0 by default, which means no spinning after being emitted.
Tilt particles as they're emitted
Checking the boxes next to Force and Drag will make particles look like they're falling more naturally - as if they have gravity applied to them.
You can set the particles to move with force in a certain direction, by adjusting the values next to Acceleration.
Increasing linear drag will cause the particles to slow down their movement through space. Increasing rotational drag will slow down their rotation.
Choose whether the particle system should be visible in the Front or Back camera.
First try reducing the Lifespan of particles. In particular, try to make sure particles don't extend beyond what can be seen in the camera. You can check this by comparing what's visible in the Viewport, with what you can see in the Simulator in Spark AR Studio.
You can also: