APEX IOFx Users Guide

NVIDIA APEX

APEX IOFx Users Guide

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Introduction

The IOFx provides the ability to control the parameters that determine if the particles should be drawn as meshes or as sprites. The parameters that determine how the mesh or sprites are drawn are also in the IOFx asset. These parameters are described in the documents referenced below:

IOFx Modifiers

There are two types of IOFx modifiers, Spawn Modifiers that set the characteristics of the particles when they are emitted and Continuous Modifiers that update the particles over time. Characteristics such as the way the particles move, their size, and color can be set and modified. There are modifiers that change the characteristics over time, particle density, velocity, and in a random manner constrained by authorable limits.

The list of parameters and their descriptions for the various modifiers are described here:

Notes:

  • All color channels (RGBA) for a particle are initialized with a value of 1.0 when spawned.
  • If a continuous modifier for color is present, no spawn modifier for color is necessary.
  • Color modifiers in the continuous modifier stack are executed in the order they appear in the stack (0 through n)
  • The first color modifier in the continuouts modifier stack ‘’sets’’ the color, following color modifiers will ‘’multiply’’ the color
  • Using a rotation modifier with an orient along screen velocity modifier (or an orient scale along screen velocity modifier) is not recommended and may result in undetermined particle behavior. If you do use both modifiers together, the modifier nearest to the bottom of the modifier stack will take predominance.

Example

IOFx Example