battle_fx

Tracers, muzzle bloom, ichor and dust: four populations, one shader, four materials. Each copy's brightness and its life come out of one instance lane, which multiplies the colour and the alpha together so a spent effect costs a blended draw of nothing. The silhouette is softened against the view angle, which is what lets a stretched box read as a streak of light and a squashed sphere as a puff of dust. lit_amount hands a population back to the scene's own lighting, for the things that are dust rather than fire.