# Scrawl-canvas v8 - Particles test 007

## Particle Force objects: generation and functionality

Particle count
Random motion intensity
Select filter

#### Test purpose

Be aware that applying a filter to a particle system can cause it to fail in interesting yet mysterious ways! In some browsers, the addition of a filter can also cause a significant degradation in canvas animation speeds

- Create a Block entity to match the canvas dimensions, to act as a generation area for an Emitter with a set number of required particles.
- Create additional forces to act on the particles.
- Create the Emitter alongside its World object and artefact entity
- Check that the 'brownian-motion' force function responds to changes in the World object's user-defined 'brownianIntensity' attribute.
- Check that the 'mouse-disruptor' force follows the mouse cursor.
- Create a set of filters. Check to make sure that selecting a filter will make it apply to all the bear images in the Demo scene.

Touch test: should work as expected

Annotated code