Game Development and Simulation with Unreal Technology

Material Expressions in Unreal Engine 4 661

SPHERICAL PARTICLE OPACITY

This expression provides a less expensive mechanism to create opacity masks that

would allow a particle to appear sph erical.

Example Usa ge: Use the output channel of a Particle Speed to drive the opacity

texture or the emissive co lor networks of a material. Connecting the result of

these networks to the Emissive or Opacity channels of a material node will create

particles that will fade as they slow down, or get more opaque and glow more as

their speeds in crease (see Figure 5.10).

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Inputs

Density: A value ranging between 0 and 1 that controls the density of the sphere

map. Default value is 1, which results in more opaque particles.

PARTICLE SUB UV

This expression can be used to ...