Option to disable shader compile error checks

Presently, when compiling shaders – three.js always checks for compile errors, this is typically the biggest time hog, and if you have a decent number of them (shaders that is) – it tends to cause considerable FPS spikes. For example, in my game it’s about a series of very janky spikes just just as you first load and try to move the camera.

Here’s the first frame:

and here’s the aggregate of the entire game load and first couple of seconds of gameplay:

as you can see, just checking for errors and retrieving error messages takes up close to 800ms.

I think it’s great to have these checks during development and it’s great to be able to keep them, but in production a lot of the time they can be irrelevant or at least it’s a developer’s call whether to get better performance or get better error reporting.

I believe it would be beneficial for developers to be able to opt-out from these error checks/reports.

There’s a separate point, that these checks can be done asynchronously in most browsers. See @toji ‘s demo: http://toji.github.io/shader-perf/

Also, I’m aware of WebGLRenderer.compile, that’s a separate point, good fit for static scenes – I’m glad we have this feature.