Chaos Phoenix is a dynamics simulator, which enables you to create fluids like liquids and gases, as well as make objects such as a ship or ice cubes float in water. It can even simulate waves that can carry these objects around, or wash them away.
The Phoenix Active Bodies feature makes this possible, by introducing Rigid Body Dynamics for active body objects.
To use Active Bodies, you’ll need to create an Active Body Solver component, and Solver node is used to specify the scene geometrywhich will partake in the Active Bodies simulation. By .
Then, in the Simulator's Liquid rollout, enable the Active Bodies parameter, and specify the Active Body Solver node.
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Note that by default, all geometries in the scene areSolid and act as obstacles to the Phoenix fluid simulation.
Active Bodies go one step further and can be pushed by the fluid or can float over the liquid surface
However, unlike Solid obstacles, which stay in place and
just
simply obstruct the movement of the fluid, Active Bodies go further by enabling objects to be pushed by the fluid, or to float over a liquid surface.
Just as the movement of Solid objects . Additionally, just like the movement Solid bodies can be animated, the movement of the Active Bodies can also be animated as well. This way, so that an Active Body can both follows follow a trajectory, and at the same time gets get pushed by the fluid.
You can balance between the influence of the animation and the fluid from an Active Body's Node Properties'Original Animation Influence optionusing the Original Animation Influence parameter, located in the Phoenix Node Properties attributes rollout, for any Active Body.
You can also set the density and other Active Body properties in the Node Properties attributes rollout as well, for each Active Body object.
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The Active Bodies simulation currently supports interaction between scene geometry and the Phoenix Liquid Simulator.
Interaction between Active Bodies and the Phoenix Fire/Smoke Simulator is not supported yet.
The Active
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Note that the Active Body Solver node sets up global
simulation parameters which affect all Active
simulation parameters, which affect all Active Body objects in the
Interaction list,
Interaction Set. This is in contrast to the Phoenix
attributes, which are unique for each Active Body.
This way
As a result, you can
have
set up several Active Body Solver nodes, each with their own solver settings and set of Active Bodies
with
, so that you can have different rigid body
behavior
behaviors for each set
.
.
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The Active Bodies simulation currently supports interaction between scene geometry and liquid simulations.
Interaction between Active Bodies and fire/smoke simulations is not supported yet.
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UI Path: ||Phoenix FD Menu|| > Create > Active Body Solver
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Solver | solver – Specifies which solver will be used for the Active Bodies scene interaction.
Bullet – Uses the Bullet solver for the Active Bodies interaction. Allows for mutual interaction between Active Bodies. Basic – Uses the legacy basic solver for the Active Bodies interaction. This solver does not support mutual interaction between Active Bodies, but does support Air Drag.
Interaction Steps | timestep_mult – Supported only when the Solver is set to Bullet. Determines how many calculations for the Active Bodies are performed between two consecutive fluid simulation steps - e.g. if the Steps Per Frame option of the fluid Simulator is 4 and the Interaction Steps of the Active Bodies are 10, then the rigid body simulation will do 40 steps per frame. Increasing the value will make the Active Bodies move smoother and increase the overall accuracy of the collisions at the expense of simulation time.
Fluid Density Multiplier | interaction_mult – Allows you to override the density of the simulated liquid. By default, 1.0 is considered 1000 kilograms per cubic meter (the density of water). Increasing this value will cause the Active Bodies to appear lighter and sink less inside the fluid simulation, and vice versa.
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On Earth, an object floats above water because of two forces: Gravity pulling it down, and the Buoyancy of the liquid pushing it up. Depending on the densities of the liquid and the floating object, those forces balance out and the object either sinks (if denser than the liquid it is submerged in) or floats.
Affect by Foam | affect_by_foam – Controls how much the Foam particles will affect the Active Bodies.
Collision Margin | collision_margin – Supported only when the Solver is set to Bullet. You can lower this parameter if you have groups Active Bodies which are in contact with one another and you want to keep them still. If the values is too high, the bodies might start pushing apart for no apparent reason. On the other hand, if the Collision Margin is too low, the simulation will slow down, and also fast moving bodies might start passing through other bodies. If the latter happens and you still need the Collision Margin to be low, you can prevent bodies from passing through one another by increasing the Interaction Steps.
Air Drag | simulate_air_drag – Applies a simple Drag force to slow down the translation and rotation of the Active Body. This option helps stabilize the motion of objects in the simulation. The Air Drag will affect the simulation only when the Basic solver is used.
Jammed Walls as Obstacles | use_jammed_walls – When enabled the Active Body Solver will use the Simulator's Jammed Walls as obstacles for the Active Bodies.
