Rewrote AudioDriverJavaScript to support multiple processor nodes.
The old (and deprecated) ScriptProcessorNode when threads are not
available, and the new AudioWorklet API when threads are enabled.
The new implementation uses two ring buffers and a shared state to
communicated with the AudioWorklet thread.
The audio.worklet.js JavaScript file is always added to the export
template, but only really used (and download) in the thread build.
The API is implemented in javascript, and generates C functions that can
be called from godot.
This allows much cleaner code replacing all `EM_ASM` calls in our C++
code with plain C function calls.
This also gets rid of few hacks and comes with few optimizations (e.g.
custom cursor shapes should be much faster now).
The size of the audio buffer was incorrectly doubled when creating the
script processor.
latencyHint is expressed in seconds, not milliseconds.
Additionally, on some browsers it actually affect the performance and
stability of the audio driver.
For this reason it has been completely disabled (interactive) and a not
has been left for future reference.
minizip documentation describes tm_mon as expecting the number of months
since January - [0, 11], but the month returned by OS.get_date() is in
the range of [1, 12].
(cherry picked from commit 5fe902244a)
Batching is mostly separated into a common template which can be used with multiple backends (GLES2 and GLES3 here). Only necessary specifics are in the backend files.
Batching is extended to cover more primitives.
A new editor plugin, specific to HTML5, that provide some extra features
needed to make the editor usable on that platform.
For now, it adds a "Download project sources" option in the "Tool" menu,
so the user can download the work done as a zip file (from the browser
storage).
This should be made available in emscripten in a decent way.
Possibly after unmount, to free the database lock and allow performing
operations on it from javascript after the Emscripten Runtime has
exited.
This fixes a "random" deadlock when quitting the editor.
I still haven't figure out the root cause, but having a bigger seems to
greatly mitigate the issue.
The new pool size (pre-allocated threads) is now 8.
No longer parse emscripten/emsdk config to detect emcc/node paths.
Use WhereIs to find "emcc" and "node", look for "node_modules" in "emcc"
path.
(cherry picked from commit 7998745237)
This should fix some of the audio stuttering issues when the HTML5
export is compiled with threads support.
The API should be ported to AudioWorklet to (hopefully) be perfect.
That though, cannot be backported to 3.2 due to extra restriction of
AudioWorklet (which only runs in SecureContext, and needs a polyfill for
Safari).
This allow the page to be considered a SecureContext if the address is
localhost (127.0.0.1/::1) and let Firefox (and future Chrome versions)
enable extra features needed for the HTML5 threaded export.
