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Particle Emitter

Parameter​

Auto Play​

  • Type: bool
  • Default: true

Loop​

  • Type: bool
  • Default: true

Duration​

  • Type: float
  • Default: 5
  • Constrain: t: t > 0

Spawn Rate​

  • Type: float float
  • Default: 10 20
  • Constrain: x: x > 0 y: y > 0

The emission time of the next particle is determined by a random value uniformly taken in this range; negative numbers are treated as 0. The two numbers are order-independent, and being equal means fixed. Same below.

Burst Count​

  • Type: float float
  • Default: 0 0

At the start of each duration, burst particles will be shot out. The intensity of each burst particle is taken as a random value uniformly in this range; negative numbers are treated as 0.

Emitter Size​

  • Type: float float float
  • Default: 1 1 1

Particles will be generated randomly and uniformly in this area; 0 means the position on that axis is fixed, and a negative number means the opposite direction.

Initial Speed​

  • Type: float float
  • Default: 0 5

Each particle takes a random value uniformly in this range; a negative number means the opposite direction.

Initial Rotation​

  • Type: float float
  • Default: 0 0

Each particle takes a random value uniformly in this range; the unit is radian, and a positive number means clockwise.

Angular Velocity​

  • Type: float float
  • Default: 0 0

Each particle takes a random value uniformly in this range; a positive number means clockwise.

Initial Size​

  • Type: float float
  • Default: 0.5 1
  • Constrain: x: x >= 0 y: y >= 0

Each particle takes a random value uniformly in this range; negative numbers are treated as 0.

Lifetime​

  • Type: float float
  • Default: 1 2
  • Constrain: t1: t1 >= 0 t2: t2 >= 0

Each particle takes a random value uniformly in this range; negative numbers are treated as 0.

Follow Camera​

  • Type: bool
  • Default: false

The particle emitter will move and rotate with the camera.

Follow Position Offset
Follow Camera = true
​

  • Type: float float float
  • Default: 0 0 0

Material​

  • Type: Material.Particle
  • Default: empty

Color over Lifetime​

  • Type: list[vec4]
  • Default: [(1, 1, 1, 1), (1, 0, 0, 0.5), (0, 0, 1, 1)]
  • Constrain: (r, g, b, τ): 0 <= r <= 1 and 0 <= g <= 1 and 0 <= b <= 1 and 0 <= τ <= 1

X Y Z correspond to the RGB color; negative numbers are treated as 0, and numbers greater than 1 are treated as 1.

W represents the keyframe time, following the rules below:

  • The start of a particle's lifetime is τ = 0, and the end is τ = 1
  • Negative numbers are treated as 0, and numbers greater than 1 are treated as 1
  • When multiple keyframes have the same time (including the out-of-range keyframes above), only the first declared keyframe is effective
  • If there's no keyframe at the start, the parameter value of the earliest keyframe is used
  • If there's no keyframe at the end, the parameter value of the latest keyframe is used
  • Between two adjacent keyframes, each parameter changes linearly

Alpha over Lifetime​

  • Type: list[vec2]
  • Default: [(0, 0), (1, 0.2), (1, 0.7), (0, 1)]
  • Constrain: (α, τ) : 0 <= α <= 1 and 0 <= τ <= 1

X represents the alpha; negative numbers are treated as 0, and numbers greater than 1 are treated as 1.

Y represents the keyframe time, with the same rules as above.

Size over Lifetime​

  • Type: list[vec2]
  • Default: [(0.3, 0), (1, 1)]
  • Constrain: (s, τ): s >= 0 and 0 <= τ <= 1

X represents the ratio relative to the particle's Initial Size; negative numbers are treated as 0.

Y represents the keyframe time, with the same rules as above.

Gravity Factor​

  • Type: float
  • Default: 0

Turbulence Intensity​

  • Type: float
  • Default: 1

Turbulence Frequency​

  • Type: float
  • Default: 0.2
  • Constrain: f: f > 0

Animation Tiles X Animation Tiles Y​

  • Type: int int
  • Default: 1 1
  • Constrain: m: 0 < m <= 32 n: 0 < n <= 32

Split the material image by the given number of tiles, and treat each tile as one frame to form a particle animation. The animation cycle is determined by the particle's Duration.