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Physarum

simulations/physarum·v1.5.1

IN:1 OUT:2

SUMMARY

The Physarum operator moves agents that sense a trail field ahead of them, turn toward the strongest reading, step forward and deposit into the field, which diffuses and decays every frame. The population organizes itself into veins, meshes and maze-solving networks, and the operator outputs the agents as points with their heading and the trail as a field carrying Weight.

Sensor distance and angle, move distance and rotation angle each scale with the trail under the agent, so agents on a strong trail can sense farther, turn sharper or move faster. The simulation runs in 3D or in the XY plane inside a simulation box, a mesh or field collider keeps the agents out of or inside a shape, and Target Feedback Loop POPs for the particles and the field re-inject both loops (Initialize, Start, Play) from downstream.

PARAMETERS

PAGEPhysarum

Target Particle Feedback Loop POP	Targetpareticlepop	A reference to a POP node downstream in the network. This reference will cause a feedback loop and re-injects the particles next frame.
Target Field Feedback Loop POP	Targetfieldpop	A reference to a POP node downstream in the network that is re-injected as the field state next frame.
[+]Simulation Space	Simspace	3D uses five sensors and a voxel trail. 2D uses three sensors in XY and a one-slice trail, ignoring input Z.
Max Axis Resolution	Maxaxisres	Sets the number of voxels along the longest axis. The other axes follow the box proportions.
[+]Simulation Resolution	Simres	Shows the resulting grid resolution (read-only).
[+]Simulation Size	Simsize	Size of the simulation box, in world units.
[+]Simulation Center	Simcenter	Sets the center of the simulation box.
Display Bounds	Displaybounds	Display the simulation box.
Initialize	Initializepulse	Initializes the POP from its input and parameters. The agents come from the input and the trail starts empty.
Start	Startpulse	Start the simulation from the initialized state.
Play	Play	Pause or play the feedback loop.
Step	Steppulse	Advance the simulation by one frame while paused.

PAGESense

Sense Scale	Sensescale	Scales the trail value the agents read before it is clamped to 1. Higher values are more binary, lower values more graded.
[+]Sense Interpolation	Senseinterp	Nearest reads one cell. Trilinear weights 8 cells, smoother on coarse grids and short sensor distances.
Sensor Distance Base	Sensordistancebase	Sets the base reach of the sensors ahead of the agent in world units, before the trail response.
Sensor Distance Power	Sensordistancepower	Sets the exponent of the trail value under the agent that modulates the sensor distance. 0 keeps it constant.
Sensor Distance Scale	Sensordistancescale	Sets the sensor distance in world units added at a sensed value of 1, scaled by the sensed value raised to Sensor Distance Power.
Sensor Angle Base	Sensoranglebase	Sets the angle of the side sensors from the heading. Angles are given in degrees.
Sensor Angle Power	Sensoranglepower	Sets the exponent of the trail value under the agent that modulates the sensor angle. 0 keeps it constant.
Sensor Angle Scale	Sensoranglescale	Sets the sensor angle added at a sensed value of 1, scaled by the sensed value raised to Sensor Angle Power. Angles are given in degrees.

PAGEMove

Move Distance Base	Movedistancebase	Sets the base move per second in world units, before the trail response.
Move Distance Power	Movedistancepower	Sets the exponent of the trail value under the agent that modulates the move distance. 0 keeps it constant.
Move Distance Scale	Movedistancescale	Sets the move per second in world units added at a sensed value of 1, scaled by the sensed value raised to Move Distance Power.
Rotation Angle Base	Rotationanglebase	Sets the turn per 1/60 second toward the stronger side, more per frame below 60 FPS. Angles are given in degrees.
Rotation Angle Power	Rotationanglepower	Sets the exponent of the trail value under the agent that modulates the rotation angle. 0 keeps it constant.
Rotation Angle Scale	Rotationanglescale	Sets the turn added at a sensed value of 1, scaled by the sensed value raised to Rotation Angle Power. Angles are given in degrees.

PAGEField

[+]Deposit Mode	Depositmode	Determines how deposits add up. Linear counts each agent once. Square Root uses the root of the count for denser aggregates without blowout.
Trail Level	Traillevel	Sets the average trail value at rest, independent of the agent count and the resolution. Lanes read 5 to 20 times this.
Decay	Decay	Sets the fraction of the trail lost per 1/60 second, the same per second at any frame rate. Low values smear the network, high values keep it crisp.
Smooth Deposit	Depositsplat	Spread each deposit over the 8 surrounding cells, for a smoother trail at low agent density.
Diffuse Strength	Diffusestrength	Sets the strength of each diffusion pass, from 0 for no blur to 1 for a full Gaussian blur.
Diffuse Radius	Diffuseradius	Sets the diffusion radius per 1/60 second as a fraction of the box's longest axis, up to 16 cells.
Diffuse Passes	Diffusepasses	Sets the number of diffusion passes per frame.

PAGECollisions

[+]Collision Type	Collisiontype	Selects the collider: none, a POP mesh (ray traced, Windows only) or a field used as an SDF volume.
Collision POP	Collisionpop	The collider, either a mesh POP or an SDF field volume.
[+]Dist Attribute (SDF)	Distattr	For a field collider, the signed distance attribute of the Collision POP, negative inside.
Solid	Solid	When on, agents inside the collider are pushed out. When off, the collider is hollow.
Keep Inside	Keepinside	When on, the collider is hollow and every outside agent is pulled back in. When off, only escaping agents are caught.
Project	Project	Place every agent on the collider surface instead of colliding.
Collision Offset	Collisionoffset	Distance the agents keep from the collider surface.
Collision Damping	Collisiondamping	Velocity lost on contact. 0 bounces and 1 stops.
[+]Transform Order	Xord	Sets the transform order of the collider.
[+]Rotate Order	Rord	Sets the order of the rotations of the collider.
[+]Translate	T	Translate the collider in the three axes.
[+]Rotate	R	Rotate the collider around the X, Y and Z axes. Angles are given in degrees.
[+]Scale	S	Scale factor for each axis of the collider.
[+]Pivot	P	The pivot point for the rotate and scale of the collider.
Uniform Scale	Scale	Specifies a uniform scale factor for the collider.
Display Geometry	Displaygeo	Enable drawing the collider, as the mesh or the field's zero surface.
[+]Display Color	Displaycolor	Sets the color of the displayed guides.

PAGECommon

Free Extra GPU Memory

Freeextragpumem

Free memory that has accumulated when output memory has grown and shrunk.

INPUTS

Input 0 POP - Particles In

OUTPUTS

Output 0 POP - Particles Out

Output 1 POP - Field