flutter3d_impeller 0.8.0

The flutter_gpu backend for flutter3d: one implementation of flutter3d_hardware, and the only place in the stack that names a graphics API.

flutter3d_impeller

flutter3d_hardware over flutter_gpu: the backend a desktop or mobile build draws through.

final device = await GpuRenderBackend.create();
final renderer = Renderer.create(device: device);

Nothing else in the stack names flutter_gpu. Swapping this for another backend changes one line of application wiring. That property is what the split exists for, and there are two more backends to prove it with.

The shader bundle

flutter_gpu wants shaders compiled ahead of time, so this package builds a bundle:

./tool/build_shaders.sh

The bundle is gitignored and its format is tied to the SDK version, so a fresh checkout has none until that runs. A test asserts it was built. It fails instead of skipping on purpose, because "CI built only one bundle" is the trap that test exists to catch.

Run it again after every shader edit. The sources live in flutter3d_shaders, and editing one changes nothing an application loads until this rebuilds. Forgetting shows up as failed to bind texture, not as a shader behaving oddly: the renderer binds a slot the new GLSL declares and the compiled binary does not have. The message names neither the shader nor the edit.

dart run tool/structure.dart compares the bundle against its sources and says which are newer, so the mistake is a red rule instead of a lost afternoon. It skips when there is no bundle, which is every checkout without impellerc.

The entry point lives here and not in flutter3d, and it has to. The script calls impellerc, which is this backend's compiler and not the engine's concern, and a scan holds the engine to naming no backend at all. An extension package outside this repository runs the same build against its own shaders:

dart run flutter3d_impeller:build_shaders

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Part of flutter3d, an independent implementation of a 3D engine for Flutter. It is not a fork or a binding of another engine, and it is not affiliated with the Flutter team. It has four switchable rendering backends: Impeller via Flutter GPU, WebGL2, WebGPU and a software rasteriser. It loads glTF, OBJ and .f3d, and has six lighting models, shadows, bloom, skinning, animation, BVH culling and picking, plus a deterministic fixed-step game layer with collision, navigation, positional audio, and gamepad and touch input. Four example games (shooter, platformer, racing, strategy) are each built on a genre package: flutter3d_game_shooter, flutter3d_game_platformer, flutter3d_game_racing, flutter3d_game_strategy. A new game starts from the editor's scaffold, which writes one from a template: https://flutter3d.pleion.dev/first-project/. Documentation: https://flutter3d.pleion.dev.