NiPSysGravityModifier

NiPSysGravityModifier is a modifier for particle systems that applies a gravity-like effect on particles in the system. It does so by dragging particles towards a NiNode in the NIF.

It is commonly used to mimic the effects of the wind, but can be used to actually pull particles down if the strength is set high enough.

It's settings are as such:

• Name: The name of the modifier. Typically used by other modifiers to target each other.
• Target: The targeted particle system.
• Active: Bool, determines whether or not the modifier is active. NiPSysModifierActiveCtlr can manipulate it.
• Gravity Object: Uses a NiNode to determine the direction of gravity. The effect is stronger over distance.
• Gravity Axis: Specifies the local direction, appears to only work per axis (i.e you would need three GravityModifiers for X, Y, and Z) and goes off a range of 0 or 1.
• Decay: How much the effect of gravity wears off over distance (lifetime or physical proximity to the object?).
• Strength: How much particles accelerate to the Gravity Object.
• Force Type: Either Planar or Spherical, or Unknown.
• Turbulence: Adds a level of randomness to the effects of gravity.
• Turbulence Scale: Multiplies the effects of Turbulence.
• World Aligned:

NiPSysGravityModifier is typically what is used to give the appearance of smoke billowing in the wind. While BSWindModifier exists, all it does is accelerate particles in the direction of the wind and wind in the engine appears to be fixed in a northwestern direction. It is only recommended for player spawned effects such as explosive weapon vfx, and NiPSysGravityModifier is better suited for environmental props.