Make a readable fire particle effect for Unity

Start from a saved baseline

Use Core Fire and the model that will carry the effect. Position the emitter before tuning its density. A torch flame, engine plume and burning object have different scale cues; judging all of them against an empty grid makes it easy to build an effect that is too large.

Save a .2vfx baseline, then change one variable per variation. Give the files meaningful names such as torch-short-life and torch-wide-base. These are local project files, not cloud saves. Keep an untouched version so a promising experiment does not overwrite your starting point.

Duration is not particle lifetime

System Duration describes the emitter’s cycle. Start Lifetime describes how long an individual particle survives. With Looping enabled, the emitter repeats; extending its Duration is not the same operation as making every flame particle live longer. Prewarm is meaningful for looping systems and changes the initial visible state.

For a controlled Unity-side experiment, start with lifetime 0.6 seconds, speed 0.8, size 0.25 and gravity modifier 0. Then change only lifetime to 1.2 seconds. These are illustrative artistic values, not a physically accurate fire model or a promise that they are the exact current 2VFX preset.

• Unity 6: Main module ↗

Shape the base before the tip

First decide how much of the model’s surface emits fire. In Unity’s Shape module, radius and cone angle affect the spawn region and initial direction. In 2VFX the Shape controls are labelled Unity-export-only: their exact native behaviour is not shown by the simplified browser preview.

After export, compare a narrow base with a wider base at the same emission rate. Then adjust size over lifetime so the particles grow and fade intentionally. Avoid changing start size, cone radius and emission at once: three simultaneous changes make diagnosis ambiguous.

• Too broad at the base: inspect the spawn radius before shortening lifetime.
• Flame hides the prop: reduce apparent size, alpha or density.
• A harsh end: inspect the colour/alpha and size curves near the final age.
• Unexpected streaks after moving the prop: check Local versus World simulation space.

Move the test into Unity

Generate a PNG atlas if the effect needs textured animation. Native Semantic keeps ParticleSystem modules editable. Baked Visual creates a separate flipbook-driven prefab from an atlas; it does not bake every module setting into a new simulation.

Install the downloaded .tgz through Package Manager and run the model/effect builder under Tools > 2VFX. Use a Unity 6.3 Built-in test project. A GLB model additionally needs a compatible glTF importer; FBX and OBJ use Unity’s native path. Fix missing assets before adjusting the effect to compensate for an import problem.

Review the whole loop at gameplay distance

Watch the start, a steady middle and the loop boundary. Move the model and orbit the camera if the actual game permits those actions. Compare a bright environment and a dark one: additive fire may feel much weaker in daylight.

A fixed seed helps repeat the same generator’s behaviour. It does not make the browser and Unity use the same random stream or shader. If you need image-led consistency, evaluate the baked representation and keep its camera-facing limitation in mind.

1. Check the silhouette with the game camera, not a close editor view.
2. Play several loops and look for a visible reset.
3. Move the prop and confirm the intended simulation space.
4. Compare the native and baked outputs as different representations, not as interchangeable promises.