flutter3d_webgl library

WebGL2 as an implementation of flutter3d_hardware.

The second backend. Its value is not only that it runs on the web: it is the first thing that can tell us whether the HAL is a seam or a description of Impeller, because a fake backend can only confirm that an interface is callable, never that it is implementable.

Status: it draws the engine's scenes. The engine names its stages — LightingModel.shaderName and the renderer's require calls — and every backend must ship a set answering to those names. This one's are generated: tool/generate_shaders.dart translates flutter3d_shaders into GLSL ES 3.00 and writes engine_shaders.dart, which tool/ci.sh regenerates and diffs, because a table nobody diffed once held a sky from before the sky was rewritten.

What it draws is measured rather than asserted. Every golden scene is recorded here as well, and test/cross_backend_test.dart holds each one to its own measured distance from the picture Impeller recorded — a budget per scene rather than one tolerance over all of them, because a tolerance wide enough for the worst scene stops watching the rest.

This paragraph said the opposite for as long as the shaders took to write, which is the trap a status line sets: it is the first thing a reader of the package sees, on pub.flutter-io.cn and in the IDE, and nothing fails when it goes out of date.