Understand how the Particle SystemA component that simulates fluid entities such as liquids, clouds and flames by generating and animating large numbers of small 2D images in the scene. More info
See in Glossary can simulate physics forces that act on a particle.
The Force over Lifetime module can change the strength of simulated physics forces on a particle based on how long the particle has existed.
Fluids are often affected by forces as they move. For example, smoke will accelerate slightly as it rises from a fire, carried up by the hot air around it. Subtle effects can be achieved by using curves to control the force over the particles’ lifetimes. Using the previous example, smoke will initially accelerate upward but as the rising air gradually cools, the force will diminish. Thick smoke from a fire might initially accelerate, then slow down as it spreads and perhaps even start to fall to earth if it persists for a long time.
The External Forces module modifies the effect of wind zonesA GameObject that adds the effect of wind to your terrain. For instance, Trees within a wind zone will bend in a realistic animated fashion and the wind itself will move in pulses to create natural patterns of movement among the tree. More info
See in Glossary and Particle System Force Fields on particles emitted by the system.
To get the best results out of this feature, create separate GameObjectsThe fundamental object in Unity scenes, which can represent characters, props, scenery, cameras, waypoints, and more. A GameObject’s functionality is defined by the Components attached to it. More info
See in Glossary with ParticleSystemForceFields components.
A TerrainThe landscape in your scene. A Terrain GameObject adds a large flat plane to your scene and you can use the Terrain’s Inspector window to create a detailed landscape. More info
See in Glossary can incorporate wind zones which affect the movement of trees on the landscape. Enabling this section allows the wind zones to blow particles from the system. The Multiplier value lets you scale the effect of the wind on the particles, since they will often be blown more strongly than tree branches.
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