Bevy Setup

Installing Rust

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• More details in the following note Rust Setup.

Create new project:

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• In your terminal run these commands:

cargo new your_bevy_prj_name
cd your_bevy_prj_name

• After running above commmands, your project folder will have a tree structure like this:

│   Cargo.lock
│   Cargo.toml
├───src
|      main.rs
└───target

• main.rs is your Root Crate which is the entry point of the program:

fn main() {
    println!("Hello, world!");
}

• Cargo.toml is the “project file” which includes:
  • Metadata
  • Dependencies
  • Build configs

[package]
name = "your_bevy_prj_name"
version = "0.1.0"
edition = "2021"
 
[dependencies]

Add Bevy to the project:

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• Method 1: cargo add bevy.
• Method 2: Add the following line bevy = "*" to your toml file:

[package]
name = "your_bevy_prj_name"
version = "0.1.0"
edition = "2021"
 
[dependencies]
bevy = "*"

• * means it will get the latest version of bevy crate. If you want to pick a specific version go to this website and check the version Bevy.

Compiling optimization:

---

• In case you want to debug the game, the complication is super slow for doing that. To optimize it, add these following lines in your toml file:

# Enable a small amount of optimization in debug mode
[profile.dev]
opt-level = 1
 
# Enable high optimizations for dependencies (incl. Bevy), but not for our code:
[profile.dev.package."*"]
opt-level = 3

Optional:

---

Feature:

• Enable bevy’s dynamic linking Feature:
  • Run cargo run --features bevy/dynamic_linking each time.
  • If you don’t want to do it each run then add the following feature to your toml file:

[dependencies]
bevy = { version = "0.13.0", features = ["dynamic_linking"] }

Compiler:

• Nightly Rust Compiler: Not stable but this gives lightly performance than the stable rust.
  • Create “rust-toolchain.toml” file
  • Then put following code:

[toolchain]
channel = "nightly"

Linker:

• Choose one of following linkers:
• Use LLD linker:
  • Windows:

cargo install -f cargo-binutils
rustup component add llvm-tools-preview

• Use mold linker: x5 faster than LLD linker but not stable and not Windows support
  • Ubuntu: sudo apt-get install mold clang

Enable fast compiles:

• Install both LLD linker and nightly rust compiler.
• Put .cargo/config.toml next to src folder.
• Copy following code in the url to config.toml file: link

Rebuild:

• Build your project again to see the significant change.
• The first time may be slow but after that it will be fast.