API Reference > imodeljs-frontend > Rendering > ParticleCollectionBuilder > transparency transparency transparency: number The default transparency for newly-added particles as an integer in [0,255], used by ParticleCollectionBuilder.addParticle if ParticleProps.transparency is omitted. Changing this value has no effect on the transparency of previously-added particles. Defined in core/frontend/src/render/ParticleCollectionBuilder.ts Line 87 Last Updated: 12 June, 2024