Deduplicate Wasm optimization instructions (#14173)

See bevyengine/bevy-website#1538 for context.

docs-template/EXAMPLE_README.md.tpl

@@ -256,61 +256,26 @@ In browsers, audio is not authorized to start without being triggered by an user
 ### Optimizing
 
 On the web, it's useful to reduce the size of the files that are distributed.
-With rust, there are many ways to improve your executable sizes.
-Here are some.
+With rust, there are many ways to improve your executable sizes, starting with
+the steps described in [the quick-start guide](https://bevyengine.org/learn/quick-start/getting-started/setup/#compile-with-performance-optimizations).
 
-#### 1. Tweak your `Cargo.toml`
-
-Add a new [profile](https://doc.rust-lang.org/cargo/reference/profiles.html)
-to your `Cargo.toml`:
-
-```toml
-[profile.wasm-release]
-# Use release profile as default values
-inherits = "release"
-
-# Optimize with size in mind, also try "s", sometimes it is better.
-# This doesn't increase compilation times compared to -O3, great improvements
-opt-level = "z"
-
-# Do a second optimization pass removing duplicate or unused code from dependencies.
-# Slows compile times, marginal improvements
-lto = "fat"
-
-# When building crates, optimize larger chunks at a time
-# Slows compile times, marginal improvements
-codegen-units = 1
-```
-
-Now, when building the final executable, use the `wasm-release` profile
-by replacing `--release` by `--profile wasm-release` in the cargo command.
+Now, when building the executable, use `--profile wasm-release` instead of `--release`:
 
 ```sh
 cargo build --profile wasm-release --example lighting --target wasm32-unknown-unknown
 ```
 
-Make sure your final executable size is smaller, some of those optimizations
-may not be worth keeping, due to compilation time increases.
-
-#### 2. Use `wasm-opt` from the binaryen package
-
-Binaryen is a set of tools for working with wasm. It has a `wasm-opt` CLI tool.
-
-First download the `binaryen` package,
-then locate the `.wasm` file generated by `wasm-bindgen`.
-It should be in the `--out-dir` you specified in the command line,
-the file name should end in `_bg.wasm`.
-
-Then run `wasm-opt` with the `-Oz` flag. Note that `wasm-opt` is _very slow_.
-
-Note that `wasm-opt` optimizations might not be as effective if you
-didn't apply the optimizations from the previous section.
+To apply `wasm-opt`, first locate the `.wasm` file generated in the `--out-dir` of the
+earlier `wasm-bindgen-cli` command (the filename should end with `_bg.wasm`), then run:
 
 ```sh
 wasm-opt -Oz --output optimized.wasm examples/wasm/target/lighting_bg.wasm
 mv optimized.wasm examples/wasm/target/lighting_bg.wasm
 ```
 
+Make sure your final executable size is actually smaller. Some optimizations
+may not be worth keeping due to compilation time increases.
+
 For a small project with a basic 3d model and two lights,
 the generated file sizes are, as of July 2022, as follows:
 
@@ -323,13 +288,6 @@ the generated file sizes are, as of July 2022, as follows:
 |"z" + "thin" + codegen-units = 1 | 5.3M | 11M |
 |"z" + "fat" + codegen-units = 1 | 4.8M | 8.5M |
 
-There are more advanced optimization options available,
-check the following pages for more info:
-
-- <https://rustwasm.github.io/book/reference/code-size.html>
-- <https://rustwasm.github.io/docs/wasm-bindgen/reference/optimize-size.html>
-- <https://rustwasm.github.io/book/game-of-life/code-size.html>
-
 ### Loading Assets
 
 To load assets, they need to be available in the folder examples/wasm/assets. Cloning this

examples/README.md

@@ -664,61 +664,26 @@ In browsers, audio is not authorized to start without being triggered by an user
 ### Optimizing
 
 On the web, it's useful to reduce the size of the files that are distributed.
-With rust, there are many ways to improve your executable sizes.
-Here are some.
+With rust, there are many ways to improve your executable sizes, starting with
+the steps described in [the quick-start guide](https://bevyengine.org/learn/quick-start/getting-started/setup/#compile-with-performance-optimizations).
 
-#### 1. Tweak your `Cargo.toml`
-
-Add a new [profile](https://doc.rust-lang.org/cargo/reference/profiles.html)
-to your `Cargo.toml`:
-
-```toml
-[profile.wasm-release]
-# Use release profile as default values
-inherits = "release"
-
-# Optimize with size in mind, also try "s", sometimes it is better.
-# This doesn't increase compilation times compared to -O3, great improvements
-opt-level = "z"
-
-# Do a second optimization pass removing duplicate or unused code from dependencies.
-# Slows compile times, marginal improvements
-lto = "fat"
-
-# When building crates, optimize larger chunks at a time
-# Slows compile times, marginal improvements
-codegen-units = 1
-```
-
-Now, when building the final executable, use the `wasm-release` profile
-by replacing `--release` by `--profile wasm-release` in the cargo command.
+Now, when building the executable, use `--profile wasm-release` instead of `--release`:
 
 ```sh
 cargo build --profile wasm-release --example lighting --target wasm32-unknown-unknown
 ```
 
-Make sure your final executable size is smaller, some of those optimizations
-may not be worth keeping, due to compilation time increases.
-
-#### 2. Use `wasm-opt` from the binaryen package
-
-Binaryen is a set of tools for working with wasm. It has a `wasm-opt` CLI tool.
-
-First download the `binaryen` package,
-then locate the `.wasm` file generated by `wasm-bindgen`.
-It should be in the `--out-dir` you specified in the command line,
-the file name should end in `_bg.wasm`.
-
-Then run `wasm-opt` with the `-Oz` flag. Note that `wasm-opt` is _very slow_.
-
-Note that `wasm-opt` optimizations might not be as effective if you
-didn't apply the optimizations from the previous section.
+To apply `wasm-opt`, first locate the `.wasm` file generated in the `--out-dir` of the
+earlier `wasm-bindgen-cli` command (the filename should end with `_bg.wasm`), then run:
 
 ```sh
 wasm-opt -Oz --output optimized.wasm examples/wasm/target/lighting_bg.wasm
 mv optimized.wasm examples/wasm/target/lighting_bg.wasm
 ```
 
+Make sure your final executable size is actually smaller. Some optimizations
+may not be worth keeping due to compilation time increases.
+
 For a small project with a basic 3d model and two lights,
 the generated file sizes are, as of July 2022, as follows:
 
@@ -731,13 +696,6 @@ the generated file sizes are, as of July 2022, as follows:
 |"z" + "thin" + codegen-units = 1 | 5.3M | 11M |
 |"z" + "fat" + codegen-units = 1 | 4.8M | 8.5M |
 
-There are more advanced optimization options available,
-check the following pages for more info:
-
-- <https://rustwasm.github.io/book/reference/code-size.html>
-- <https://rustwasm.github.io/docs/wasm-bindgen/reference/optimize-size.html>
-- <https://rustwasm.github.io/book/game-of-life/code-size.html>
-
 ### Loading Assets
 
 To load assets, they need to be available in the folder examples/wasm/assets. Cloning this