Particle movement
Particle movement operators refer specifically to translation. Rotation is kept separate, since many particle systems don't want it.
Contents
Movement Basic
Moves particles with their internal velocities.
- gravity
- A global force which accumulates over each particle's lifetime.
- drag
- How resistant the particles are to motion. 1 means almost total resistance. Anything above 1 flings the particles off into outer space!
- max constraint passes
- Todo: Unknown. Similar to the value on phys_constraintsystem?
Movement Dampen Relative to Control Point
Drains a particle's internal velocity as it approaches the specified control point. If no other forces are acting on it, the particle will eventually stop.
This can be used with Movement Lock to Control Point (and its distance fade property) to have a control point "capture" particles near it then draw them along. It can also lock endpoints of a line of particles while allowing the middle section to move freely.
- control point number
- The control point to dampen near.
- falloff range
- The distance over which the dampening effect will fade out to nothing.
- dampen scale
- The strength of movement dampening. This is not a maximum value; the effect will continue for as long as a particle is within range. Todo: What is the units/second equivalent of 1?
Movement Lerp to Hitbox
- control point number
- lifetime lerp start
- lifetime lerp end
Movement Lock to Bone
Works like Movement Lock to Control Point, but is designed for use in conjunction with Position on Model Random initializer. Locks all particles emitted from a given control point to their associated bone.
- control point number
- The control point that references the model in question.
- lifetime start/end fade
- The time at which to start/end fading the lock relative to particle lifespan (0-1).
Movement Lock to Control Point
Causes particles to inherit the movement and optionally rotation of a control point.
- control point number
- The control point to lock to.
- distance fade range
- The maximum distance at which the CP will scoop up particles. A gentle falloff gradient is used.
Note:Using both distance fade range and lock rotation will result in particles spiralling in towards the CP until they stop moving. - lock rotation
- Makes the particles respond to CP rotation as well as translation. Starts disabled.
- start_fadeout_min
- start_fadeout_max
- start_fadeout_exponent
- end_fadeout_min
- end_fadeout_max
- end_fadeout_exponent
- Defines when particles start and stop being affected by the movement lock, as a proportion of their lifespan. The exponent values are normals which bias which result from the fade in/out range is most likely to be picked.
Bug:If there is a wide gap between the min and max fadeout times, some particles will continue to judder after they should have stopped. [todo tested in?]
Movement Maintain Offset
Positions particles in a straight line relative to one another.
- Desired Offset
- The gap between each particle in units (but see Scale by Radius).
- Local Space CP
- [Todo]
- Scale by Radius
- Multiplies Desired Offset by the radius of the particle.
Movement Maintain Position Along Path
Arranges particles into a line between two control points, accounting for the movement of either.
- maximum distance
- How far away either end of the path can trail from its control point. See also cohesion strength.
- use existing particle count
- Map the current number of particles in the system to the path, overriding the manual value. Recommended, as getting the number wrong leads to flickering.
- cohesion strength
- How strong the attachment to each control point is. At 0, the path will have to be dragged. At 1, it will never stray from the CPs.
- start control point number
- end control point number
- bulge
- bulge control
- mid point position
- maximum distance
- particles to map from start to end
- See Position Along Path Sequential.
Movement Match Particle Velocities
Forces particles to inherit the velocity of the first one emitted. Can copy the recorded value to a control point.
- Control Point to Broadcast Speed and Direction To
- The given CP is moved to a position that represents the current velocity.
- Direction Matching Strength
- Speed Matching Strength
- Two normals which determine the degree to which emitted particles match the first. Can both be set to 0 if you just want the CP output.
Movement Max Velocity
Limits the speed of all particles in this system.
- Maximum Velocity
- Limit to this value.
- Override Max Velocity from this CP
- Limit to the first value of this control point's position vector.
Movement Place On Ground
Tries to ensure particles float above a surface somewhere beneath them. See also the Position Modify Place On Ground initializer.
- collision group
- What to consider solid. Todo: Values?
NONEseems to mean everything. - CP movement tolerance
- [Todo]
- include water
- Consider water a valid ground surface?
- kill on no collision
- Remove the particle if it can't find the ground.
- max trace length
- How far down to search for the ground.
- offset
- Height above ground to float.
- reference CP 1
- reference CP 2
- [Todo]
- trace offset
- [Todo]
