flutter3d_cpu

flutter3d_hardware rasterised in Dart, with no GPU under it.

final device = CpuDevice(
  width: 240,
  height: 160,
  shaders: CpuShaderLibrary(builtinCpuShaders()),
);
final pixels = await device.readPixels(frame);

Two things use it. The golden images are drawn with it, so a machine with no display can render a whole frame and compare it. And a test can mount a real game and ask what is on the screen — which is how three bugs that every simulation test passed were finally caught, all of them in the seam between a simulation that was right and a picture that was wrong.

It shares nothing with either hardware backend — no driver, no shading language, no command buffer — which is what makes agreeing with them mean something. test/cross_backend_test.dart compares its output against the Impeller reference set with a per-scene budget.

Comparing frames

compareFrames counts the pixels two frames disagree about, with the same default threshold tool/golden.sh uses, and reports the worst single-channel step beside the count.

Part of flutter3d, an independent implementation of a 3D engine for Flutter — not a fork or a binding of another engine, and not affiliated with the Flutter team. Three switchable rendering backends: Impeller via Flutter GPU, WebGL2, and a software rasteriser. glTF, OBJ and .f3d loading, six lighting models, shadows, bloom, skinning, animation, BVH culling and picking; a deterministic fixed-step game layer with collision, navigation, positional audio, and gamepad and touch input. Three example games — shooter, platformer, racing — each built on its genre package: flutter3d_game_shooter, flutter3d_game_platformer, flutter3d_game_racing. A new game starts from apps/flutter3d_template_app. Documentation: flutter3d.pleion.dev.