UFCFX5-15-3Mobile Device Development Particle Systems

UFCFX5-15-3Mobile Device Development Agenda Role of Particle Systems in Visual Effects (VFX) Particle System Types Concepts of Particles Dynamics of Particles Typical Components and Elements of a Particle System Unity Particle Systems Examples

UFCFX5-15-3Mobile Device Development Role of Particle Systems Most objects in a 3D environment are depicted as solid objects, e.g. meshes, 2D apps use sprites. Meshes and sprites depict solid objects with a well - defined shape. However, other entities are more intangible and transient, e.g. smoke, fire, liquids and crystal ‘magic’ effects. Particle systems typically provide a means to portray the visual characteristics and motion of such entities.

UFCFX5-15-3Mobile Device Development Particle Systems Types A particle system can be static or animated Each particle can be displayed all at once (static) or displayed over time (animated) Usually, most particle effects featured in a 3D environment are animated, but the particle system would be able to produce some static effects if required Examples of static particle effects would be hair or fur, these are typically found in 3D Animation systems such as Maya and 3D Studio MAX

UFCFX5-15-3Mobile Device Development Concepts of Particles Particles are small images or meshes moved and displayed in large numbers. Each particle represents a small portion of the resulting entity, which move together in a motion that attempts to portray the dynamics of the real-world entity Such natural dynamic systems have been the study of much research toward the development and evolution of CGI-based particle systems.

UFCFX5-15-3Mobile Device Development Dynamics of Particles Each particle has a predefined lifetime, typically of a few seconds, during which the particle can undergo various changes in colour, orientation and velocity. The system emits particles within a region of space such as a sphere, cone, or arbitrary mesh Particles can be moved under the influence of gravity and or have their own force of movement that can interact with other physics-based systems in the scene.

UFCFX5-15-3Mobile Device Development Typical Components of Particle Systems Emitter The emitter acts as the source of the particles. Where the emitter is positioned in 3D space determines the initial creation point of the particles. Animator The animator determines how the particles motion behave during their existence in the system. Renderer The renderer is responsible for displaying the particles and applying colour and any associated textures. Properties of colour can be modified over time e.g. colour gradients.

UFCFX5-15-3Mobile Device Development ‘Light Snow’ Emitter e.g. Minimum Emission = 25 Maximum Emission = 50

UFCFX5-15-3Mobile Device Development ‘Light Snow’ Animator Animate the Colours

UFCFX5-15-3Mobile Device Development Renderer ‘Billboard’ makes the particle face the viewer

UFCFX5-15-3Mobile Device Development ‘Flame’ Particle System The Flame particle system has four sub components Three Emitters Inner Core, Outer Core, Smoke A Light Source

UFCFX5-15-3Mobile Device Development

UFCFX5-15-3Mobile Device Development ‘Flame’ Light Source

UFCFX5-15-3Mobile Device Development Latest System Unity now features an alternative particle system using the same concepts and principles as the original system. It now includes facilities for collisions detection of particles on other objects. However, all the current particle FX assets are based on the original system.

UFCFX5-15-3Mobile Device Development Summary Particle Systems attempt to simulated non solid object dynamic behaviour and visual characteristics. They are typically used to created fire, dust, liquid, and crystal effects. Most particle systems will consist of a particle Emitter, Animator and Renderer The number of properties associated with each component is extensive, developers would usually choose a suitable base particle system to evolve into the required VFX. Unity has a new particle system component which features similar elements and principles but now has collision detection features. All the current FX are based on the original system Naturally occurring dynamic systems have been the focus of research in the development and evolution of CGI-based particle systems.