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. A test can also mount a real game and ask what is on the screen. That is how three bugs were caught that every simulation test had passed; all three sat in the seam between a simulation that was right and a picture that was wrong.

It shares no driver, shading language or command buffer with either hardware backend, so when its output agrees with theirs, the agreement is independent evidence. 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. 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: flutter3d.pleion.dev/first-project/. Documentation: flutter3d.pleion.dev.