Druid web examples

This crate generates and builds all the necessary files for deploying druid examples to the web.

Building

You will need cargo and wasm-pack for building the code and a simple server like http for serving the web pages.

First build with

> wasm-pack build --target web --dev

This step has two main functions:

1. It generates an HTML document for each of the `druid` examples with a script that
   calls the appropriate function in the JavaScript module exposing the raw Wasm.
2. It builds the Wasm binary which exposes all functions annotated with `#[wasm_bindgen]`.
3. It builds the JavaScript module that loads the Wasm binary and binds all the exposed
   functions to JavaScript functions so they can be called directly from JavaScript.

To preview the build in a web browser, run

> http

which should start serving the crate root folder containing index.html.

Finally, point your browser to the appropriate localhost url (usually http://localhost:8000) and you should see a list of HTML documents -- one for each example.

When you make changes to the project, re-run wasm-pack build --target web --dev and you can see the changes in your browser when you refresh -- no need to restart http.

New Examples

New examples that can be built against the web target should have an associated impl_example!(<example_name>) entry added to lib.rs. Examples that don't support the web target should be specified in the EXCEPTIONS list defined at the top of the build.rs script.