flutter3d_shaders

The engine's shader sources, in GLSL, for every backend to compile.

There is one shared copy so that backends cannot drift apart: flutter3d_impeller builds them into a flutter_gpu bundle, flutter3d_webgl translates them to GLSL ES 3.00, and flutter3d_cpu implements the same stages in Dart against the same declarations.

A shader that exists in one backend and not the others gives a picture that differs by platform, and nothing notices. This has happened: the sky was rewritten here while the browser's copy of the table was a year out of date, so two backends drew different skies until a generated file was finally diffed.


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.

Libraries

flutter3d_shaders
What the engine asks a backend's bundle for, readable from Dart.
stage_bindings
What every stage in the engine's bundle keeps once compiled: the uniform blocks and samplers a draw through it must bind and may bind. Read off impellerc's Metal reflection, so a resource the source declares and the compiler dropped is not here. FakeBackend(stageBindings: stageBindings) holds a renderer to it on the VM.
typed_blocks
A class per uniform block the engine's stages declare, one preallocated array per member, laid out as the compiler lays it out. Filled in place and bound with PassEncoder.bindBlock.
uniform_blocks
How impellerc lays out the uniform blocks of every stage in the engine's bundle: each member's byte offset, byte length, element count and reflected type, in declaration order. Per stage, because one block name can be wider in one stage than another.