Instance Property

fresnelExponent

The reflectivity exponent SceneKit uses when rendering the particle’s image as a cube map. Animatable.

Declaration

@property(nonatomic) CGFloat fresnelExponent;

Discussion

This property only takes effect when the particleImage property is an array of six images defining a cube map. In this case, SceneKit renders each particle as a reflective sphere.

The fresnel exponent modulates the reflectivity of a surface from different view angles. At the default value of 1.0, reflections have the same intensity across the entire surface of the particle. At higher values, the edges of the particle are more reflective than the center.

You can animate changes to this property’s value. See Animating SceneKit Content.

See Also

Specifying Particle Appearance

particleSize

The rendered size, in units of the scene’s world coordinate space, of the particle image. Animatable.

particleSizeVariation

The range of randomized particle sizes. Animatable.

particleColor

The color of newly spawned particles. Animatable.

particleColorVariation

The ranges of randomized particle color components. Animatable.

particleImage

The texture image SceneKit uses to render each particle.

stretchFactor

A multiplier for stretching particle images along their direction of motion. Animatable.