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Why Balaur

Why Balaur

· 2 min read
Dragos
Balaur

I also maintain Godot Rapier Physics: Rapier's 2D and 3D physics as a drop-in replacement for Godot's. Balaur started there.

What the addon does​

  • Rapier 2D and 3D in Godot, from the asset store.
  • Deterministic, and cross platform deterministic.
  • Physics state serializes and reloads exactly.
  • Fluids, IK, no ghost collisions, better stacking.

Where it stops​

Only the physics server is deterministic. The scene tree, rendering, input and scripting sit outside the physics state, and keeping them in step is the game's job. Documented on the addon's determinism page.

Two reasons for a new engine:

  • I wanted the whole game deterministic, not one server inside it.
  • A fix in Godot waits on review, a merge and the next release. I wanted to fix something and ship it the same day.

What Balaur does instead​

  • The whole tick is deterministic. Fixed 60 Hz step, a digest per tick, run --record and replay --verify, rollback.
  • Network replies queue and land at the start of a tick: a replay covers logins and retries with no network.
  • Rapier is still the physics, 2D and 3D. Built by Sébastien Crozet.
  • Scenes are TOML. Scripts are Rune and hot reload in milliseconds:

Where it is​

0.1.0 is on the Download page. Compare says when to pick Godot, Bevy or Fyrox instead.