I might sometimes build different profiles, so this gives me somewhere
to change them. It *does not work* for debug builds because of how cargo
works. So that sucks.
I can't think of a reason anyone would seriously want to change the
target, but I've made that a variable, too. WASM64 exists, but I can't
get a read on it's availability across browsers. The benefit seems to be
accessing >4GB of memory, which is not important for this project. Other
targets are for "desktop" platforms and so shouldn't be using the
makefile.
https://www.gnu.org/software/make/manual/html_node/Multiple-Targets.html
The previous recipe told Make that each file could be produced by
running wasm-bindgen. The more correct expression is that *both* files
will be produced at the same time.
Now Make knows to only invoke the command one time to get both files if
either is out of date. Previously, multi-job builds (`-j2`) could build
the files twice -- one invocation for each out-of-date file.
This makes the output folder "required to exist" and not "required to be
more recent."
The folder's timestamp is updated when files are written into it. The
files inside depend on the folder existing. The result is that the WASM
and JS files are considered very slightly older than the folder that
contains them. The result is that the folder is up-to-date but it's
contents are not, thus re-building them and *again* updating the folder
timestamp. The makefile was stuck constantly rebuilding things that are
actually up-to-date.
Oops, it's not supposed to have a file suffix! It's a bit annoying that
it still produces both a WASM and JS file, just not the right ones (and
no _bg.wasm at all). Especially without any warning that it is doing
something different than normal. Oh well.
Call with `make -f makefile_web` to produce a web root for serving. Use
target "boids_web_root.tar" to bundle the files into a tarball. For...
publishing... or something.
The `wasm-server-runner` program seems to supply it's own index.html and
is doing *something* regarding MIME types -- hosting a dev build of the
Boids program results in the browser complaining about "" (empty string)
being an invalid MIME type.
I want my own index.html during testing, and I can't figure out why the
MIME type info is wrong. I've decided to automate the web-root build
process and serve it up with whatever webserver I have on hand.