Special Particle Maps
There are two special maps designed specifically for use with particles:
Particle Age. This has three slots for maps or colors that can be blended based on particle age. It varies from particle to particle and is applied relatively.
Particle Mblur. This changes the color of the leading and trailing edges of moving particles. It is most commonly used in the Opacity slot of the material, but can also be used in other slots.
Space Warps for Particles
There are lots of space warps that are used as fields to affect particle motion. They can be applied individually or globallyfor example, a single space warp can affect several particle systems at once. Space warps for particles are divided into two groups: Forces and Deflectors. Forces affect the motion of particles during their lifetime and Deflectors work as collision objects for particles.
The Forces group of particle space warps includes the following:
Motor. This is a dynamic force used to impart a torque effect on particles.
Push. This is a simple repulsive force causing particles to push away along the space warp's direction.
Vortex. This is new to 3ds max 4 and causes a special rotational-well effect similar to the vortex of a tornado.
Drag. This is a useful motion dampener that causes particles to slow down a given percentage over time. This dampening effect can be isolated along certain axes.
Path Follow. This forces particle motion to conform to a shape object in the scene.
PBomb. This is another repulsive force but varies in shape. A repulsive force can be applied spherically, cylindrically, or from a plane.
Displace. This is another useful space warp that uses an image or map to cause motion perturbation. It modulates the amplitude of the forces based on grayscale values, with white as full force and black as no force. The extents of the force depend on the shape of the gizmo being used.
Gravity. This is a common variable force that uses Newtonian physics to cause an attraction or repulsion spherically or planar with acceleration.
Wind. This is similar to gravity and works in both Spherical and Planar mode, but adds perturbation controls in the form of turbulence.
There are three basic categories of Deflectors, differentiated by their shape. All three categories include planar, spherical, and universal (object-based) shapes:
Deflector. This is a standard Deflector that has bounce and friction controls, including Deflector, SDeflector, and UDeflector.
DynaFlect. This is a special type of Deflector used in dynamics simulations. DynaFlect Deflectors have the added capability of enabling the user to include particle systems in dynamics simulations. They add physics-based parameters, such as mass, and include PDynaFlect, SDynaFlect, and UDynaFlect.
OmniFlect. This is a variation of Deflectors that adds the capability of both reflecting and refracting particles. OmniFlect Deflectors include POmniFlect, SOmniFlect, and UOmniFlect.