Particle position

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Particle position initializers decide the location(s) at which particles are created.

Warning: Particles will appear at world origin if there is no position initializer.

Position Along Path Random

See Position Along Path Sequential.

Position Along Path Sequential

See Position Along Path Sequential.

Position Along Ring

Use with render_rope. Note the loose ends on the right-hand side.

Particles are created the edge of a circle. The circle can be thickened to a 3D torus.

control point number
The ring centres on this control point.
even distribution
Creates particles at regular intervals around the ring. Normally their position is random.
even distribution count
The number of locations at which particles are created. Ignored if even distribution is disabled.
initial radius
Number of units from the control point to the ring line.
max initial speed
min initial speed
Gives particles an initial velocity pointing away from the control point.
XY velocity only
Particles with initial speed will not have any velocity in the Z axis. Only relevant if thickness is used.
Override CP
A control point from which to take override values for this operator.
  • Radius = X
  • Thickness = Y
  • Initial speed = Z
pitch
roll
Rotates the ring. Very hight values are required for some reason; 5150 is roughly a 90° twist.
thickness
Particles can spawn up to this far away from the ring line.

Position From Chaotic Attractor

Some kind of time-based random position generator?

Relative Control point number
To do
Pickover A Parameter
Pickover B Parameter
Pickover C Parameter
Pickover D Parameter
To do
Scale
Multiply the final positions by this factor
Speed Max
Speed Min
Gives particles an initial velocity pointing away from the control point.
Uniform speed
To do

Position from Parent Cache

To do

Local Offset Max
Local Offset Min
To do
Set Normal
To do

Position From Parent Particles

To do: Spawn particles at the position of existing ones in the parent? No apparent effect.

Inherited Velocity Scale
How much of the velocity of the parent particles each child particle inherits.
Random Parent Particle Distribution
To do

Position In CP Hierarchy

Particles creation positions "crawl" along a chain of control points. Seems quite buggy.

growth time
How long it takes for particles to travel from the first CP to the last.
distance_bias
distance_bias_absolute_value
To do
use highest supplied end point
To do
start control point number
end control point number
bulge
bulge control
mid point position
See Position Along Path Sequential.

Position Modify Offset Random

Moves particles after their initial position has already been calculated.

offset max
offset min
The range within which positions will be offset. Displayed as a box in the preview window.
offset proportional to radius
Multiplies the offset values by the radius of each particle.
offset in local space
Whether the min/max values should be considered relative to the world or to the control point they were emitted from.
Bug: The helper box is displayed incorrectly when this property is active.

Position Modify Place On Ground

Tries to move particles to the first solid surface beneath them.

This initializer has the same properties as the Movement Place On Ground operator.

Position Modify Warp Random

Position Along Ring with a warp of 1,2,1.

Scales the position of each particle. This can be used to contort the emission shape, and is how the elongated rings seen in Portal are created. Initial velocities are also warped.

warp min
warp max
The warping factor in three dimensions. 1 1 1 results in no warping.
control_point_number
The control point relative to which warp will be applied.
warp transition time
Treats the min/max as start and end sizes for a transition that takes place over this many seconds.
warp transition start time
When the transition will start.
reverse warp
Makes the transition run backwards.

Position on Model Random

Creates particles within the hitboxes of a control point's associated entity.

Burning effects often use this operator.
control_point_number
The control point to get an entity from.
desired hitbox
The hitbox index within which to create particles. Use -1 to target all of them.
direction bias
Biases which parts of the hitbox (or whole model if all of them are active) receive the most particles. 0 0 10 will ensure that almost all particles spawn in the upper half. To do: Precise meaning of the value.
force to be inside model
Tries to ensure that particles aren't created outside the model's surface.
Note:Particles generated more than a few units away will not be affected.
model hitbox scale
Scale the size of each hitbox by this factor (for particle placement only).

Position Within Box Random

Particles are positioned at a random location inside a box.

control point number
The control point to centre the box on.
min
max
Defines the far corners of the box.
use local space
Applies the control point's rotation and local offset (if any) to the box.

Position Within Sphere Random

Particles are positioned at random inside a sphere or hollow shell, and are optionally given an initial velocity.

A half-dome of stars.
control_point_number
The control point to centre the sphere on.
distance_min
distance_max
The nearest and farthest distance from the control point at which to place particles.
distance_bias
The likelihood of particles being created in each axis (X, Y, Z). Setting any of the three numbers to 0 will flatten the sphere in that direction, while setting to 10 will lead to roughly 10 times as many particles near the far ends of that axis. Useful for creating discs, rings, and polar effects.
distance_bias_absolute_value
If any axis is non-zero, all particles will be eliminated from that hemisphere. Use distance_bias to alter the effect (e.g. a negative value will flip the hemisphere from one side to the other).
bias_in_local_system
Sets whether the biasing values should be interpreted locally to the central control point. If they are, then the CP's rotation affects the outcome of the initializer.
speed_min
speed_max
Particles will be initialised with a velocity that repulses them from the centre of the sphere at this many units per second.
Note:A Movement Basic operator is required for this to have any visible effect.
speed_random_exponent
A factor for how likely the minimum speed is to be applied.
  • 0 means that all particles will move at maximum speed
  • 1 means an even spread
  • Above 1 makes particles increasingly likely to move at minimum speed
speed_in_local_coordinate_system_min
speed_in_local_coordinate_system_max
In addition to movement away from the central control point, you can initialise particles with a random velocity. As the name suggests, these directions are always relative to the central control point's rotation.

Category:Particle initializers