Keep the smoke volume readable
Smoke usually needs a different balance from fire: a longer visible lifetime, a broader silhouette and enough transparency for overlapping layers. Begin with Soft Smoke and a low amount. Increase the spread gradually while checking whether the silhouette still points back to its source.
Attach the emitter to a model to judge scale. A plume that looks convincing in an empty preview can overwhelm a small exhaust pipe. Save a baseline before testing a larger particle size; changing size and emission together makes it difficult to know which change caused a dense dark cloud.
Make a smoke sprite sheet
Generate 4×4 flipbook creates a transparent PNG atlas with 16 procedural frames. Download PNG gives you the image itself; Save .2vfx also preserves the model and particle settings. The atlas is an animated image asset, not a simulation cache.
- Choose Soft Smoke in the editor and set the attachment point.
- Adjust spread, overall scale and the core/edge colours.
- Generate the flipbook and inspect its transparent edge at the intended display size.
- Use Baked Visual for a flipbook-driven Unity prefab, or Native Semantic for editable particle settings.
Avoid dark edges and muddy overlap
A dark fringe is not always a bad texture. Straight-alpha and premultiplied-alpha images need compatible blending. Filtering can also pull dark RGB from nearly transparent pixels into the visible edge. Test the same image on black, grey and white before repainting the source.
Smoke normally obscures what is behind it, while additive effects brighten the background. An additive smoke material may look acceptable against black but disappear in a bright scene. Inspect the imported material and render pipeline as well as the PNG.
- Use the alpha-blending guide for a numerical test rather than judging only a checkerboard.
- Browser-only previews do not validate engine collision, lighting or soft-particle depth behaviour.
- Unity export currently targets Built-in; no URP, HDRP or Niagara package is claimed.