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POP Fluid applies forces between nearby particles of a POP Object in an attempt to maintain the goal Particle Separation. This node can be used to capture simple fluid effects (such as cohesion and basic surface tension) with points.
This optional input has two purposes.
First, if it is wired to other POP nodes, they will be executed prior to this node executing. The chain of nodes will be processed in a top-down manner.
Turns this node on and off. The node is only active if this value is greater than 0. This is useful to control the effect of this node with an expression.
This is activation of the node as a whole. You can’t use this parameter to deactivate the node for certain particles.
An overall scale applied to the actual timestep.
This parameter governs which particle properties will be affected. Best results are achieved in Update Positions mode.
The particle positions and velocities will be updated.
Only particle velocities will be updated.
force attribute will be updated.
When Projection Type is set to Update Velocities, this parameter controls how the constraint velocity is to be combined with the particle’s velocity. Value of 1 causes the particle’s velocity to be completely overridden, while value of 0 ignores the constraint velocity altogether.
The desired distance between nearby particles.
The number of iterations of constraint projection to perform. More iterations allow Particle Separation to be matched more closely at the cost of running time.
The stiffness determines how closely Particle Separation will be matched. Stiffer constraints have a lower tolerance for deviation from the goal, but can be unstable.
The maximum acceleration that can be applied to a particle by constraints. Lowering this parameter can help in mitigating instabilities.
Particles apply repulsive forces on their neighbors to prevent clustering. This parameter determines the distance (as a fraction of the particle’s kernel radius) at which this force is equal to Tensile Strength.
Magnitude of the repulsive forces between nearby particles.
Enabling viscosity causes velocity diffusion, resulting in more coherent motion among nearby particles.
Counteracts energy dissipation by maintaining vortices.
Use the OpenCL device to accelerate computations.
The desired number of points in each particle’s neighborhood.
Range of allowed kernel radii, as multiples of a global radius. Disabling this option forces use of a fixed kernel radius for all particles.
The number of points in a particle’s neighborhood is not allowed to exceed this value. Only applies when Adaptive Range is turned off.
Number of times neighborhoods are constructed in a substep.
It is only safe to reduce Construction Frequency below 1 if particles are not being deleted from the bound geometry.
The name of the simulation data to apply the POP node to. This commonly is Geometry, but POP Networks can be designed to apply to different geometry if desired.
The name of the point attribute that determines the constraint stiffness for each particle. Note that the value of this attribute will be scaled by Constraint Stiffness to obtain the actual stiffness.
When enabled, the last computed density for each particle is stored in the specified attribute.