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ReiLua Manual

ReiLua - Enhanced Edition

> A modified version of ReiLua with embedded main.lua, embedded assets, splash screens, and asset loading system

About This Version

This is an enhanced version of ReiLua featuring:

What is ReiLua?

ReiLua brings the power and simplicity of Raylib to the beginner-friendly Lua language in a straightforward manner. It is a loose binding to Raylib - some functions are excluded and some are added. The concept of pointing to a "main.lua" file and accessing functions "init", "update", and "draw" is borrowed from the Löve game framework.

Note: ReiLua is lovingly handcrafted and will likely contain bugs and documentation errors, so it would be much appreciated if you would report any such findings. Reilua means "fair" in Finnish.

Attributions

This enhanced version is built upon:

Core Framework

Enhancements Added

Additional Components

Font

Status

ReiLua is WIP and some planned raylib functionality is still missing, but it already has over 1000 functions. Current Raylib version is 5.5.

Included Submodules

Missing Features

List of some MISSING features that are planned to be included:

Roadmap

Quick Start

For Game Developers

Development Mode (Fast Iteration):

# 1. Create your game files
GameFolder/
├── main.lua
├── assets/
│   ├── player.png
│   └── music.wav

# 2. Run ReiLua pointing to your game folder
ReiLua.exe GameFolder/

# Or from your game folder
cd GameFolder
path/to/ReiLua.exe

# Skip splash screens during development
ReiLua.exe --no-logo

# Enable console for debugging
ReiLua.exe --log --no-logo

Release Mode (Single Executable):

# See "Building for Release" section below

Basic Example

Create a main.lua file:

local textColor = RL.BLACK
local textPos = { 192, 200 }
local textSize = 20
local text = "Congrats! You created your first window!"

function RL.init()
	RL.SetWindowTitle( "First window" )
	RL.SetWindowState( RL.FLAG_VSYNC_HINT )
end

function RL.update( delta )
	if RL.IsKeyPressed( RL.KEY_ENTER ) then
		local winSize = RL.GetScreenSize()
		local measuredSize = RL.MeasureTextEx( RL.GetFontDefault(), text, textSize, 2 )

		textColor = RL.BLUE
		textPos = { winSize[1] / 2 - measuredSize[1] / 2, winSize[2] / 2 - measuredSize[2] / 2 }
	end

	if RL.IsKeyPressed( RL.KEY_SPACE ) then
		textColor = RL.RED
		textPos = { 192, 200 }
	end
end

function RL.draw()
	RL.ClearBackground( RL.RAYWHITE )
	RL.DrawText( text, textPos, textSize, textColor )
end

Run it:

ReiLua.exe --no-logo

Framework Functions

ReiLua looks for a 'main.lua' or 'main' file as the entry point. There are seven Lua functions that the framework will call:

All functionality can be found in "API.md".

Enhanced Features

1. Splash Screens

This version includes customizable splash screens that display at startup:

Screen 1: Custom text - Bold text on Raylib red background (customizable) Screen 2: "Made using" - Displays Raylib and ReiLua logos side-by-side

Each screen fades in (0.8s), displays (2.5s), and fades out (0.8s) for a total of ~8 seconds.

Skip During Development:

ReiLua.exe --no-logo

Customize:

See SPLASH_SCREENS.md for full documentation.

2. Asset Loading System

Beautiful loading screen with progress tracking:

function RL.init()
    -- List your assets
    local assets = {
        "assets/player.png",
        "assets/enemy.png",
        "assets/background.png",
        "assets/music.wav",
    }

    -- Start loading with progress
    RL.BeginAssetLoading(#assets)

    -- Load each asset
    for i, path in ipairs(assets) do
        RL.UpdateAssetLoading(path)

        -- Your loading code
        if path:match("%.png$") then
            textures[i] = RL.LoadTexture(path)
        elseif path:match("%.wav$") then
            sounds[i] = RL.LoadSound(path)
        end
    end

    -- Finish loading
    RL.EndAssetLoading()
end

Features:

See ASSET_LOADING.md for full documentation.

3. Embedded Lua Files

Bundle all your Lua code into the executable for easy distribution:

# Copy Lua files to build directory
cd build
copy ..\your_game\*.lua .

# Build with embedding
cmake .. -DEMBED_MAIN=ON
cmake --build . --config Release

Result: Single executable with all Lua code embedded!

4. Embedded Assets

Package images, sounds, fonts, and other assets into your executable:

# Create assets folder and copy files
cd build
mkdir assets
copy ..\your_game\assets\* assets\

# Build with embedding
cmake .. -DEMBED_ASSETS=ON
cmake --build . --config Release
Your Lua code doesn't change! Use the same paths: 
-- Works in both development and release
playerImg = RL.LoadTexture("assets/player.png")
music = RL.LoadSound("assets/music.wav")

See EMBEDDING.md for full documentation.

5. Console Control (Windows)

By default, ReiLua runs without a console window for a clean user experience. Enable it for debugging:

# Show console for debugging
ReiLua.exe --log

# Combine with other options
ReiLua.exe --log --no-logo
ReiLua.exe --log path/to/game

This shows:

6. Automated Build Scripts

One-command builds for development and release:

Development Build (Fast Iteration):

# Windows
scripts\build_dev.bat

# Linux/Unix
chmod +x scripts/build_dev.sh
scripts/build_dev.sh

Release Build (Distribution):

# Prepare files first
cd build
copy ..\your_game\*.lua .
mkdir assets
copy ..\your_game\assets\* assets\

# Build release
cd ..

# Windows
scripts\build_release.bat

# Linux/Unix
scripts/build_release.sh

See BUILD_SCRIPTS.md for full documentation.

Command Line Options

ReiLua [Options] [Directory to main.lua or main]

Options:
  -h, --help       Show help message
  -v, --version    Show ReiLua version
  -i, --interpret  Interpret mode [File name]
  --log            Show console window for logging (Windows only)
  --no-logo        Skip splash screens (development)

Examples

# Run game in current directory
ReiLua.exe

# Run game in specific folder
ReiLua.exe path/to/game/

# Development mode (no splash, with console)
ReiLua.exe --log --no-logo

# Interpreter mode (run single script)
ReiLua.exe -i script.lua

# Show help
ReiLua.exe --help

# Show version
ReiLua.exe --version

Object Unloading

Some objects allocate memory that needs to be freed when no longer needed. By default, objects like Textures are unloaded by the Lua garbage collector. However, it's generally recommended to handle this manually in more complex projects:

RL.SetGCUnload()

Interpreter Mode

ReiLua can run single Lua files using interpreter mode:

ReiLua -i hello.lua

The given file will be called with dofile.

Generate API Documentation

Generate API.md and ReiLua_API.lua from the build folder:

ReiLua -i ../tools/docgen.lua
Tip: Use tools/ReiLua_API.lua in your project folder to provide annotations when using "Lua Language Server".

Building from Source

Prerequisites

You'll need to statically link Raylib and Lua to create the executable. This simplifies distribution, especially on Linux where different distros use different library versions.

Note: Lua header files are from Lua 5.4.0. If using a different version, replace them.

Windows

1. Install Tools

2. Build Raylib

# Download Raylib source
# Run w64devkit.exe and navigate to raylib/src
cd raylib/src
mingw32-make

# Copy libraylib.a to ReiLua/lib folder
copy libraylib.a path\to\ReiLua\lib\

3. Build Lua

Download Lua source from https://github.com/lua/lua

Modify Lua's makefile:

# Change this:
MYCFLAGS= $(LOCAL) -std=c99 -DLUA_USE_LINUX -DLUA_USE_READLINE
# To this:
MYCFLAGS= $(LOCAL) -std=c99

# Comment out or remove:
MYLIBS= -ldl -lreadline

Build:

# In w64devkit, navigate to Lua folder
mingw32-make

# Copy liblua.a to ReiLua/lib folder
copy liblua.a path\to\ReiLua\lib\

4. Build ReiLua

Quick Method (Recommended):

cd ReiLua
scripts\build_dev.bat

Manual Method:

cd ReiLua\build
cmake -G "MinGW Makefiles" ..
mingw32-make

5. Test

cd build
ReiLua.exe ..\examples\snake\

If you see a low-res snake racing off the window, success! Press Enter to reset.

Linux

1. Install Dependencies

sudo apt install build-essential cmake

2. Build Raylib and Lua

Compile Raylib and Lua by following their instructions. They will compile to libraylib.a and liblua.a by default.

Move both .a files to the ReiLua/lib folder.

3. Build ReiLua

Quick Method (Recommended):

cd ReiLua
chmod +x scripts/build_dev.sh
scripts/build_dev.sh

Manual Method:

cd ReiLua/build
cmake ..
make

4. Test

./ReiLua ../examples/snake/

MacOS

Not tested, but should work similarly to Linux.

Raspberry Pi

Works best when Raylib is compiled using PLATFORM=DRM. See Raylib build instructions for Raspberry Pi.

Compile ReiLua with:

cmake .. -DDRM=ON
Note: DRM should be launched from CLI, not in X.

Web (Emscripten)

Compile Raylib for web following its instructions: https://github.com/raysan5/raylib/wiki/Working-for-Web-(HTML5)

1. Compile Lua for Web

Modify Lua's makefile:

# Change:
MYCFLAGS= $(LOCAL) -std=c99 -DLUA_USE_LINUX -DLUA_USE_READLINE
# To:
MYCFLAGS= $(LOCAL) -std=c99

# Change:
MYLIBS= -ldl -lreadline
# To:
MYLIBS= -ldl

# Change:
CC= gcc
# To:
CC= emcc

# Change:
CFLAGS= -Wall -O2 $(MYCFLAGS) -fno-stack-protector -fno-common -march=native
# To:
CFLAGS= -Wall -O2 $(MYCFLAGS) -fno-stack-protector -fno-common

# Change:
AR= ar rc
# To:
AR= emar

# Change:
$(AR) $@ $?
# To:
$(AR) rcs $@ $?

Build with make if emsdk environmental variables are correct.

2. Prepare Libraries

Put libraylib.a and liblua.a into ReiLua/lib/web/.

3. Create Resources Folder

cd ReiLua/build
mkdir resources
# Copy main.lua to resources/
# Copy assets to resources/

Structure:

ReiLua/
└── build/
    └── resources/
        ├── main.lua
        └── assets/

4. Build

cd build
cmake .. -DCMAKE_TOOLCHAIN_FILE=/emsdk/upstream/emscripten/cmake/Modules/Platform/Emscripten.cmake -DPLATFORM=Web
make

5. Test

python -m http.server 8080

Access in browser: localhost:8080/ReiLua.html

Complete Release Workflow

Step 1: Prepare Your Game

MyGame/
├── main.lua
├── player.lua
├── enemy.lua
├── assets/
│   ├── player.png
│   ├── enemy.png
│   └── music.wav

Step 2: Copy Files to Build Directory

cd ReiLua/build

# Copy all Lua files
copy ..\MyGame\*.lua .

# Copy assets
mkdir assets
copy ..\MyGame\assets\* assets\
# Or: xcopy /E /I ..\MyGame\assets assets

Step 3: Build Release

cd ..
scripts\build_release.bat
# Or: scripts/build_release.sh on Linux

Step 4: Test

cd build
ReiLua.exe --log

Verify:

Step 5: Distribute

mkdir Distribution
copy ReiLua.exe Distribution\YourGameName.exe

Your game is now a single executable ready for distribution!

Customizing Your Executable

Change Executable Name

Edit CMakeLists.txt:

project( YourGameName )  # Change from "ReiLua"

Add Custom Icon

Replace icon.ico with your own icon file, then rebuild.

Edit Executable Properties

Edit resources.rc:

VALUE "CompanyName", "Your Studio Name"
VALUE "FileDescription", "Your Game Description"
VALUE "ProductName", "Your Game Name"
VALUE "LegalCopyright", "Copyright (C) Your Name, 2025"

Customize Splash Screens

Edit src/splash.c:

const char* text = "YOUR STUDIO NAME";  // Change this

Replace logos:

# Replace these files before building
logo/raylib_logo.png
logo/reilua_logo.png

Setting Up Zed Editor

Zed is a modern, high-performance code editor. Here's how to set it up for ReiLua development:

Install Zed

Download from: https://zed.dev/

Setup Lua Language Support

1. Open Zed 2. Press Cmd+Shift+P (Mac) or Ctrl+Shift+P (Windows/Linux) 3. Type "install language server" and select Lua 4. Zed will automatically install the Lua Language Server

Configure for ReiLua

Create .zed/settings.json in your project root:

{
  "lsp": {
    "lua-language-server": {
      "settings": {
        "Lua": {
          "runtime": {
            "version": "Lua 5.4"
          },
          "diagnostics": {
            "globals": ["RL"]
          },
          "workspace": {
            "library": ["ReiLua_API.lua"]
          }
        }
      }
    }
  },
  "languages": {
    "Lua": {
      "format_on_save": "on",
      "formatter": "language_server"
    }
  }
}

Copy ReiLua API Definitions

Copy tools/ReiLua_API.lua to your project folder. This provides autocomplete and documentation for all ReiLua functions.

copy path\to\ReiLua\tools\ReiLua_API.lua your_game\

Keyboard Shortcuts

Useful Zed shortcuts for Lua development:

Extensions

Install useful extensions: 1. Press Ctrl+Shift+X / Cmd+Shift+X 2. Search and install:

Workspace Setup

Create a workspace for ReiLua projects:

1. Open your game folder in Zed 2. File → Add Folder to Workspace 3. Add the ReiLua source folder (for reference) 4. File → Save Workspace As...

This lets you easily reference ReiLua source while developing your game.

Debugging

For debugging Lua code with Zed:

1. Use print() statements liberally 2. Run ReiLua with --log flag to see output 3. Use RL.TraceLog() for more detailed logging:

RL.TraceLog(RL.LOG_INFO, "Player position: " .. x .. ", " .. y)
RL.TraceLog(RL.LOG_WARNING, "Low health!")
RL.TraceLog(RL.LOG_ERROR, "Failed to load asset!")

Terminal Integration

Run ReiLua directly from Zed's terminal:

1. Press ` Ctrl+ ` / Cmd+ ` to open terminal 2. Run your game:

path\to\ReiLua.exe --log --no-logo

Tips for ReiLua Development in Zed

1. Use Multiple Cursors: Alt+Click to add cursors, great for batch edits 2. Split Views: Ctrl+\ to split editor for side-by-side editing 3. Symbol Search: Ctrl+T / Cmd+T to search for functions 4. Zen Mode: Ctrl+K Z for distraction-free coding 5. Live Grep: Ctrl+Shift+F to search across all files

Documentation

Comprehensive Guides

Quick References

Troubleshooting

Common Issues

Game doesn't start:

Assets not loading:

Splash screens don't show:

Lua files not embedded:

Assets not embedded:

Build fails:

Getting Help

1. Check documentation files listed above 2. Review the examples in examples/ folder 3. Use --log` flag to see detailed error messages 4. Check your file paths and directory structure

Contributing

Contributions are welcome! This is an enhanced version with additional features. When contributing:

1. Test thoroughly with both development and release builds 2. Update documentation if adding features 3. Follow existing code style 4. Test on multiple platforms if possible

License

ReiLua is licensed under the zlib/libpng license. See LICENSE file for details.

Third-Party Licenses

Contact & Links

Version Information

---

Happy Game Development!

Embedding

Embedding main.lua into Executable

When you're ready to ship your game, you can embed all Lua files and asset files directly into the executable.

Development vs Release Workflow

Development Build (Fast Iteration)

During development, use external files for quick iteration.

Setup:

GameFolder/
├── ReiLua.exe
├── main.lua
├── player.lua
└── assets/
    ├── player.png
    └── music.wav

Build:

cd build
cmake ..
cmake --build .

Benefits:

Release Build (Single Executable)

For distribution, embed everything into one file.

Setup:

cd build

# Copy Lua files to build directory
copy ..\main.lua .
copy ..\player.lua .

# Create assets folder and copy files
mkdir assets
copy ..\player.png assets\
copy ..\music.wav assets\

Build:

# Configure with embedding
cmake .. -DEMBED_MAIN=ON -DEMBED_ASSETS=ON

# Build release
cmake --build . --config Release

Result:

Distribution/
└── YourGame.exe  (Everything embedded!)

Benefits:

Quick Start

Embedding Lua Files

1. Copy your Lua files to the build directory:

   copy main.lua build\main.lua
   copy player.lua build\player.lua

2. Build with EMBED_MAIN option:

   cd build
   cmake .. -DEMBED_MAIN=ON
   cmake --build . --config Release

Command Line Options

ReiLua supports several command-line options:

ReiLua [Options] [Directory to main.lua or main]

Options:
  -h, --help       Show help message
  -v, --version    Show ReiLua version
  -i, --interpret  Interpret mode [File name]
  --log            Show console window for logging (Windows only)

Console/Logging

By default, ReiLua runs without a console window for a clean user experience. To enable console output for debugging:

# Run with console for debugging
ReiLua.exe --log

# You can also combine with other options
ReiLua.exe --log path/to/game

# Or with interpret mode
ReiLua.exe --log -i script.lua

This is useful during development to see:

Complete Release Workflow

Here's a complete step-by-step guide to prepare your game for release:

Step 1: Organize Your Project

Ensure your project has this structure:

MyGame/
├── main.lua
├── player.lua
├── enemy.lua
├── player.png
├── enemy.png
├── music.wav
└── icon.ico (optional)

Step 2: Customize Branding (Optional)

Change executable icon:

# Replace ReiLua's icon with yours
copy MyGame\icon.ico ReiLua\icon.ico

Edit executable properties: Open ReiLua\resources.rc and modify:

VALUE "CompanyName", "Your Studio Name"
VALUE "FileDescription", "Your Game Description"
VALUE "ProductName", "Your Game Name"
VALUE "LegalCopyright", "Copyright (C) Your Name, 2025"

Change executable name: Edit ReiLua\CMakeLists.txt:

project( YourGameName )  # Change from "ReiLua"

See CUSTOMIZATION.md for full details.

Important: Asset Paths

Keep your paths consistent! The embedding system now preserves the assets/ prefix, so use the same paths in both development and release: 
--  Correct - works in both dev and release
playerImage = RL.LoadTexture("assets/player.png")
backgroundImg = RL.LoadTexture("assets/background.png")
musicSound = RL.LoadSound("assets/music.wav")

Your Lua code doesn't need to change between development and release builds!

Step 3: Prepare Build Directory

cd ReiLua\build

# Copy all Lua files
copy ..\MyGame\*.lua .

# Create assets folder
mkdir assets

# Copy all asset files (images, sounds, etc.)
copy ..\MyGame\*.png assets\
copy ..\MyGame\*.wav assets\
copy ..\MyGame\*.ogg assets\
# Or copy entire folders
xcopy /E /I ..\MyGame\images assets\images
xcopy /E /I ..\MyGame\sounds assets\sounds

Step 4: Build Release

# Configure with embedding enabled
cmake .. -DEMBED_MAIN=ON -DEMBED_ASSETS=ON

# Build in release mode
cmake --build . --config Release

Step 5: Test Release Build

# Test with console to verify everything loaded
YourGameName.exe --log

# Test production mode (no console)
YourGameName.exe

Check console output for:

Step 6: Package for Distribution

# Create distribution folder
mkdir ..\Distribution
copy YourGameName.exe ..\Distribution\

# Optional: Add README, LICENSE, etc.
copy ..\README.txt ..\Distribution\

Your game is now ready to distribute as a single executable!

Workflow Summary

| Stage | Build Command | Files Needed | Result | |-------|--------------|--------------|--------| | Development | cmake .. && cmake --build . | Lua + assets external | Fast iteration | | Testing | cmake .. -DEMBED_MAIN=ON && cmake --build . | Lua in build/ | Test embedding | | Release | cmake .. -DEMBED_MAIN=ON -DEMBED_ASSETS=ON && cmake --build . --config Release | Lua + assets in build/ | Single .exe |

Troubleshooting

Problem: "No .lua files found in build directory"

# Solution: Copy Lua files to build directory
copy ..\*.lua .

Problem: "No files found in assets folder"

# Solution: Create assets folder and copy files
mkdir assets
copy ..\*.png assets\

Problem: Game crashes on startup

# Solution: Run with --log to see error messages
YourGameName.exe --log

Problem: Assets not loading

Notes

Customizing Your Executable

Want to add your own icon and version info to the executable? See CUSTOMIZATION.md for details on:

Asset Loading

Asset Loading System

ReiLua includes a built-in asset loading system with a loading screen UI that shows progress while assets are being loaded.

Features

API Functions

RL.BeginAssetLoading(totalAssets)

Initialize asset loading progress tracking and show the loading screen.

Parameters:

Example:

RL.BeginAssetLoading(10)  -- We're loading 10 assets

---

RL.UpdateAssetLoading(assetName)

Update the loading progress and display current asset being loaded.

Parameters:

Example:

RL.UpdateAssetLoading("player.png")

Call this after each asset is loaded to update the progress bar.

---

RL.EndAssetLoading()

Finish asset loading and hide the loading screen.

Example:

RL.EndAssetLoading()

Quick Example

function RL.init()
    -- List of assets to load
    local assetsToLoad = {
        "assets/player.png",
        "assets/enemy.png", 
        "assets/background.png",
        "assets/music.wav",
    }
    
    -- Begin loading
    RL.BeginAssetLoading(#assetsToLoad)
    
    -- Load each asset
    for i, path in ipairs(assetsToLoad) do
        RL.UpdateAssetLoading(path)  -- Update progress
        
        -- Load the actual asset
        if path:match("%.png$") or path:match("%.jpg$") then
            textures[i] = RL.LoadTexture(path)
        elseif path:match("%.wav$") or path:match("%.ogg$") then
            sounds[i] = RL.LoadSound(path)
        end
    end
    
    -- Done!
    RL.EndAssetLoading()
end

Complete Example

local assets = {}

local assetsToLoad = {
    {type="texture", name="player", path="assets/player.png"},
    {type="texture", name="enemy", path="assets/enemy.png"},
    {type="texture", name="background", path="assets/background.png"},
    {type="sound", name="music", path="assets/music.wav"},
    {type="sound", name="shoot", path="assets/shoot.wav"},
    {type="font", name="title", path="assets/title.ttf"},
}

function RL.init()
    RL.SetWindowTitle("My Game")
    
    -- Start loading with progress
    RL.BeginAssetLoading(#assetsToLoad)
    
    -- Load all assets
    for i, asset in ipairs(assetsToLoad) do
        -- Show current asset name on loading screen
        RL.UpdateAssetLoading(asset.name)
        
        -- Load based on type
        if asset.type == "texture" then
            assets[asset.name] = RL.LoadTexture(asset.path)
        elseif asset.type == "sound" then
            assets[asset.name] = RL.LoadSound(asset.path)
        elseif asset.type == "font" then
            assets[asset.name] = RL.LoadFont(asset.path)
        end
    end
    
    -- Loading complete!
    RL.EndAssetLoading()
    
    print("Game ready!")
end

function RL.update(delta)
    -- Your game logic
end

function RL.draw()
    RL.ClearBackground(RL.RAYWHITE)
    
    -- Use loaded assets
    if assets.background then
        RL.DrawTexture(assets.background, {0, 0}, RL.WHITE)
    end
    
    if assets.player then
        RL.DrawTexture(assets.player, {100, 100}, RL.WHITE)
    end
end

Loading Screen Appearance

The loading screen features a clean 1-bit pixel art style:

Design:

Elements:

Background:

Color Palette:

Style Inspiration:

Customization

If you want to customize the loading screen appearance, you can modify the colors and sizes in src/lua_core.c in the drawLoadingScreen() function.

Performance Tips

1. Call UpdateAssetLoading AFTER loading - This ensures the progress updates at the right time 2. Load assets in order of importance - Load critical assets first 3. Group similar assets - Load all textures, then sounds, etc. 4. Use descriptive names - Shows better feedback to users

Example Asset Loading Patterns

Pattern 1: Simple List

local files = {"player.png", "enemy.png", "music.wav"}
RL.BeginAssetLoading(#files)
for i, file in ipairs(files) do
    RL.UpdateAssetLoading(file)
    -- load file
end
RL.EndAssetLoading()

Pattern 2: With Types

local assets = {
    textures = {"player.png", "enemy.png"},
    sounds = {"music.wav", "shoot.wav"},
}
local total = #assets.textures + #assets.sounds

RL.BeginAssetLoading(total)
for _, file in ipairs(assets.textures) do
    RL.UpdateAssetLoading(file)
    -- load texture
end
for _, file in ipairs(assets.sounds) do
    RL.UpdateAssetLoading(file)
    -- load sound
end
RL.EndAssetLoading()

Pattern 3: Error Handling

RL.BeginAssetLoading(#files)
for i, file in ipairs(files) do
    RL.UpdateAssetLoading(file)
    
    if RL.FileExists(file) then
        -- load file
    else
        print("Warning: " .. file .. " not found")
    end
end
RL.EndAssetLoading()

When to Use

Use the loading system when:

You can skip it when:

✨ Benefits

The loading system makes your game feel polished with just a few lines of code!

Splash Screens

Splash Screens

ReiLua includes a built-in splash screen system that displays splash screens before your game loads. This gives your game a polished appearance right from startup.

Overview

When you run your ReiLua game, it automatically shows two splash screens in sequence:

1. Custom Text - Clean, bold text on Raylib red background (similar to Squid Game style) 2. "Made using" - Text with Raylib and ReiLua logos displayed side-by-side

Each splash screen:

Features

Always Embedded

The logo images are always embedded into the executable in both development and release builds. This means:

Asset Loading Integration

The splash screens display before your game's asset loading begins. This means:

1. User starts your game 2. Splash screens play (~8 seconds) 3. Your RL.init() function runs 4. Asset loading with progress indicator (if you use it) 5. Your game starts

This creates a smooth, polished startup experience.

Skipping Splash Screens (Development)

During development, you often need to test your game repeatedly. Waiting for splash screens every time can slow down your workflow. Use the --no-logo flag to skip them:

# Windows
ReiLua.exe --no-logo

# Linux/Mac
./ReiLua --no-logo

# With other options
ReiLua.exe --log --no-logo
./ReiLua --no-logo path/to/game/
Note: The --no-logo flag only works in development. In release builds, users should see the full splash screen sequence.

Technical Details

How It Works

The splash screen system is implemented in C and runs before any Lua code executes:

1. Logo Embedding: During build, scripts/embed_logo.py converts PNG files to C byte arrays 2. Initialization: Before calling RL.init(), the engine initializes splash screens 3. Display Loop: A dedicated loop handles timing, fading, and rendering 4. Cleanup: After completion, resources are freed and Lua code begins

Files

Build Integration

The CMakeLists.txt automatically:

1. Runs scripts/embed_logo.py during build 2. Generates embedded_logo.h with logo data 3. Defines EMBED_LOGO flag 4. Compiles splash.c with the project

No manual steps required - it just works!

Customization

Changing Splash Screen Text

To change the default text to your studio name:

1. Open src/splash.c 2. Find the splash drawing function 3. Change the text line:

   const char* text = "YOUR STUDIO NAME";

4. Rebuild the project

Note: Use ALL CAPS for the Squid Game-style aesthetic.

Changing Logos

To use different logos:

1. Replace logo/raylib_logo.png and/or logo/reilua_logo.png with your images 2. Recommended size: 256x256 or smaller (logos are auto-scaled to max 200px) 3. Format: PNG with transparency support 4. Rebuild the project - logos will be automatically embedded

Changing Timing

To adjust how long each screen displays:

1. Open src/splash.c 2. Modify these constants at the top:

   #define FADE_IN_TIME 0.8f    // Seconds to fade in
   #define DISPLAY_TIME 2.5f    // Seconds to display fully
   #define FADE_OUT_TIME 0.8f   // Seconds to fade out

3. Rebuild the project

Removing Splash Screens Entirely

If you don't want any splash screens:

1. Open src/main.c 2. Find this block:

   /* Show splash screens if not skipped */
   if ( !skip_splash ) {
       splashInit();
       // ... splash code ...
       splashCleanup();
   }

3. Comment out or remove the entire block 4. Rebuild the project

Example: Complete Startup Sequence

Here's what a typical game startup looks like with everything enabled:

ReiLua.exe MyGame/

User Experience: 1. Splash Screen 1 (4.1 seconds)

2. Splash Screen 2 (4.1 seconds)

3. Asset Loading (varies)

4. Game Start

Best Practices

1. Keep --no-logo for Development: Always use --no-logo during active development 2. Test Without Flag: Occasionally test without --no-logo to ensure splash screens work 3. Customize for Your Studio: Change the text and logos to match your branding 4. Consider Total Time: Splash (~8s) + Loading (varies) = Total startup time 5. Optimize Loading: Keep asset loading fast to maintain a good first impression

Troubleshooting

Splash Screens Don't Show

Problem: Game starts immediately without splash screens Solutions:

Logos Appear Corrupted

Problem: Logos display incorrectly or not at all Solutions:

Compilation Errors

Problem: Build fails with logo-related errors Solutions:

Command Reference

# Development (skip splash)
ReiLua --no-logo

# Development with logging
ReiLua --log --no-logo

# Production/testing (full splash)
ReiLua

# Help
ReiLua --help

---

The splash screen system adds a polished touch to your ReiLua games with minimal effort. Customize it to match your studio's branding and give players a great first impression!

Build Scripts

Build Scripts Documentation

ReiLua includes automated build scripts for easy development and release builds.

Available Scripts

Development Build Scripts

Release Build Scripts

Development Build

Purpose

Fast iteration during game development with external Lua files and assets.

Usage

Windows:

scripts\build_dev.bat

Linux/Unix:

chmod +x scripts/build_dev.sh
scripts/build_dev.sh

Features

Output

Release Build

Purpose

Create a single-file executable for distribution with all code and assets embedded.

Preparation

Before running the release build, prepare your files:

cd build

# Copy all Lua files
copy ..\your_game\*.lua .
# Or: cp ../your_game/*.lua .

# Copy assets
mkdir assets
copy ..\your_game\assets\* assets\
# Or: cp -r ../your_game/assets/* assets/

Usage

Windows:

scripts\build_release.bat

Linux/Unix:

chmod +x scripts/build_release.sh
scripts/build_release.sh

Features

Output

Build Configuration

The release build automatically configures:

Customizing Your Executable

Adding Custom Icon

1. Replace icon.ico with your own icon file 2. Keep the same filename or update resources.rc 3. Rebuild

Changing Executable Properties

Edit resources.rc to customize:

VALUE "CompanyName", "Your Studio Name"
VALUE "FileDescription", "Your Game Description"
VALUE "ProductName", "Your Game Name"
VALUE "LegalCopyright", "Copyright (C) Your Name, 2025"

Renaming the Executable

Edit CMakeLists.txt:

project( YourGameName )  # Line 6

After building, the executable will be named YourGameName.exe.

Workflow Examples

Development Workflow

# Initial setup
scripts\build_dev.bat

# Edit your Lua files in your game directory
# ... make changes ...

# Just run - no rebuild needed!
cd your_game
path\to\build\ReiLua.exe

# If you modify C code, rebuild
scripts\build_dev.bat

Release Workflow

# 1. Prepare files
cd build
copy ..\your_game\*.lua .
mkdir assets
copy ..\your_game\assets\* assets\

# 2. Build release
cd ..
scripts\build_release.bat

# 3. Test
cd build
ReiLua.exe --log

# 4. Distribute
# Copy build\ReiLua.exe to your distribution folder

Troubleshooting

"CMake configuration failed"

"No Lua files found"

"Build failed"

Development build embedding warning

Script Features

Safety Features

User Friendly

Notes

Customization

Customizing Your ReiLua Executable

This guide explains how to customize the ReiLua executable with your own branding.

Overview

You can customize:

Quick Customization Checklist

1. Changing the Executable Name

The easiest customization - change "ReiLua.exe" to "YourGame.exe".

Steps

1. Open CMakeLists.txt 2. Find line 6 (near the top):

   project( ReiLua )

3. Change to your game name:

   project( MyAwesomeGame )

4. Rebuild:

   cd build
   cmake ..
   cmake --build . --config Release

Result: Executable is now named MyAwesomeGame.exe

2. Adding a Custom Icon

Replace the default icon with your game's icon.

Requirements

Steps

1. Create or convert your image to .ico format 2. Replace icon.ico in the ReiLua root folder with your icon 3. Keep the same filename (icon.ico) or update resources.rc:

   IDI_ICON1 ICON "your_icon.ico"

4. Rebuild the project

Tip: Many online tools can convert PNG to ICO:

3. Customizing Executable Properties

When users right-click your .exe and select "Properties", they see file information. Customize this to show your game details.

Steps

1. Open resources.rc 2. Find the VERSIONINFO section 3. Modify these values:

1 VERSIONINFO
FILEVERSION     1,0,0,0      // Change version numbers
PRODUCTVERSION  1,0,0,0      // Change product version
FILEFLAGSMASK   0x3fL
FILEFLAGS       0x0L
FILEOS          VOS_NT_WINDOWS32
FILETYPE        VFT_APP
FILESUBTYPE     VFT2_UNKNOWN
BEGIN
    BLOCK "StringFileInfo"
    BEGIN
        BLOCK "040904b0"
        BEGIN
            VALUE "CompanyName",      "Your Studio Name"           // Your company/studio
            VALUE "FileDescription",  "Your Game - An awesome game"  // Game description
            VALUE "FileVersion",      "1.0.0.0"                    // File version string
            VALUE "InternalName",     "YourGame"                   // Internal name
            VALUE "LegalCopyright",   "Copyright (C) 2025 Your Name"  // Copyright notice
            VALUE "OriginalFilename", "YourGame.exe"               // Original filename
            VALUE "ProductName",      "Your Game"                  // Product name
            VALUE "ProductVersion",   "1.0.0.0"                    // Product version string
        END
    END
    BLOCK "VarFileInfo"
    BEGIN
        VALUE "Translation", 0x409, 1200
    END
END

Common Values

FileVersion / ProductVersion Format: Major, Minor, Patch, Build CompanyName Examples: FileDescription: LegalCopyright:

4. Rebuild the project

4. Customizing Splash Screens

Change the text and logos that appear when your game starts.

Changing Splash Screen Text

1. Open src/splash.c 2. Find the splash drawing function (around line 150) 3. Change this line:

   const char* text = "YOUR STUDIO NAME";
Style Tips:

Changing Splash Screen Logos

1. Create or find your logos:

2. Replace these files:

   logo/raylib_logo.png  → Your game logo
   logo/reilua_logo.png  → Your studio logo (or keep ReiLua logo as credit)

3. Logo sizing:

4. Rebuild the project - logos are automatically embedded

Changing Splash Screen Timing

1. Open src/splash.c 2. Modify these constants at the top:

   #define FADE_IN_TIME 0.8f    // Seconds to fade in (default: 0.8)
   #define DISPLAY_TIME 2.5f    // Seconds fully visible (default: 2.5)
   #define FADE_OUT_TIME 0.8f   // Seconds to fade out (default: 0.8)
Recommendations:

Changing Splash Screen Colors

1. Open src/splash.c 2. Find color definitions:

   // First splash screen background (Raylib red)
   Color bgColor = (Color){ 230, 41, 55, 255 };  // Change these RGB values
   
   // Second splash screen background (Black)
   Color bg = BLACK;  // Change to any color
Color Examples:

5. Customizing the Loading Screen

Change the appearance of the asset loading screen.

Steps

1. Open src/lua_core.c 2. Find the drawLoadingScreen() function 3. Modify colors and style:

// Background color
Color bgColor = BLACK;  // Change background

// Text color
Color textColor = WHITE;  // Change text color

// Progress bar fill color
Color fillColor = WHITE;  // Change bar fill

// Border color
Color borderColor = WHITE;  // Change borders

Customizing Loading Text

// In drawLoadingScreen() function
const char* loadingText = "LOADING";  // Change to "LOADING GAME", etc.

Changing Progress Bar Size

int barWidth = 200;   // Default 200px, change as needed
int barHeight = 16;   // Default 16px, change as needed
int borderThick = 2;  // Border thickness

6. Complete Rebranding Example

Here's a complete example of rebranding ReiLua as "Space Quest":

1. CMakeLists.txt

project( SpaceQuest )

2. resources.rc

VALUE "CompanyName",      "Cosmic Games Studio"
VALUE "FileDescription",  "Space Quest - Explore the Galaxy"
VALUE "FileVersion",      "1.0.0.0"
VALUE "InternalName",     "SpaceQuest"
VALUE "LegalCopyright",   "Copyright (C) 2025 Cosmic Games"
VALUE "OriginalFilename", "SpaceQuest.exe"
VALUE "ProductName",      "Space Quest"
VALUE "ProductVersion",   "1.0.0.0"

3. icon.ico

Replace with your space-themed icon

4. src/splash.c

const char* text = "COSMIC GAMES STUDIO";

5. logo/ folder

logo/raylib_logo.png  → Your game logo (space ship, planet, etc.)
logo/reilua_logo.png  → Studio logo (keep ReiLua logo for credit)

6. Build

cd build
cmake ..
cmake --build . --config Release

Result: SpaceQuest.exe with all your custom branding!

7. Advanced: Removing ReiLua Branding

If you want to completely remove ReiLua references:

Remove "Made with ReiLua" Logo

1. Open src/splash.c 2. Find drawMadeWithSplash() function 3. Comment out or modify the function to only show your logo

Remove Second Splash Screen

1. Open src/main.c 2. Find the splash screen loop 3. Modify to only call your custom splash

Note: Please keep attribution to Raylib and ReiLua in your game's credits or about screen as a courtesy!

8. Build and Test

After making any customizations:

# Clean build (recommended after customizations)
cd build
rm -rf *  # Or: rmdir /s /q * on Windows
cmake ..
cmake --build . --config Release

# Test with console
YourGame.exe --log

# Test production mode
YourGame.exe

Verify:

Checklist: Release-Ready Customization

Before releasing your game:

Tips for Polish

1. Consistent Branding: Use the same colors, fonts, and style across splash screens, loading screen, and in-game UI

2. Icon Quality: Invest time in a good icon - it's the first thing users see

3. Version Management: Update version numbers for each release

4. Legal Info: Always include proper copyright and attribution

5. Test Everything: Test your branded executable on a clean system

6. Keep Credits: Mention Raylib and ReiLua in your game's credits screen

Troubleshooting

Icon doesn't change:

Properties don't update:

Splash screens don't show changes:

Executable name unchanged:

Additional Resources

Icon Creation Tools

Image Editing

Color Picking

---

Now your ReiLua executable is fully branded and ready to represent your game!

Editor Setup

Zed Editor Setup for ReiLua

This guide explains how to set up autocomplete, type hints, and documentation for ReiLua in Zed Editor.

---

Method 1: Using Lua Language Server (Recommended)

Zed uses the Lua Language Server (LuaLS) for Lua support. ReiLua includes tools/ReiLua_API.lua with LuaLS annotations.

Setup Steps

1. Install Lua Language Server in Zed

Zed should automatically install LuaLS when you open a Lua file. If not:

1. Open Zed 2. Go to Extensions (Cmd/Ctrl + Shift + X) 3. Search for "Lua" 4. Install the Lua extension

2. Configure Your Project

Create a .luarc.json file in your project root:

{
  "runtime.version": "Lua 5.4",
  "workspace.library": [
    "${3rd}/luassert/library",
    "${3rd}/busted/library"
  ],
  "completion.enable": true,
  "diagnostics.globals": [
    "RL"
  ],
  "workspace.checkThirdParty": false
}

3. Copy tools/ReiLua_API.lua to Your Project

Copy tools/ReiLua_API.lua to your game project folder:

# From ReiLua directory
cp tools/ReiLua_API.lua /path/to/your/game/project/

Or on Windows:

Copy-Item tools/ReiLua_API.lua "C:\path\to\your\game\project\"

4. (Optional) Create Library Directory

For better organization, create a library directory:

your-game/
├── main.lua
├── .luarc.json
└── .lua/
    └── tools/ReiLua_API.lua

Update .luarc.json:

{
  "runtime.version": "Lua 5.4",
  "workspace.library": [".lua"],
  "completion.enable": true,
  "diagnostics.globals": ["RL"],
  "workspace.checkThirdParty": false
}

---

Method 2: Global Configuration (All Projects)

To make ReiLua API available for all projects:

Windows

1. Create directory: %USERPROFILE%\.luarocks\lib\lua\5.4\ 2. Copy tools/ReiLua_API.lua to this directory 3. Add to global LuaLS config:

Location: %APPDATA%\Zed\settings.json or via Zed settings 
{
  "lsp": {
    "lua-language-server": {
      "settings": {
        "Lua.workspace.library": [
          "C:\\Users\\YourName\\.luarocks\\lib\\lua\\5.4"
        ],
        "Lua.diagnostics.globals": ["RL"]
      }
    }
  }
}

Linux/macOS

1. Create directory: ~/.lua/reilua/ 2. Copy tools/ReiLua_API.lua to this directory 3. Update Zed settings:

{
  "lsp": {
    "lua-language-server": {
      "settings": {
        "Lua.workspace.library": [
          "~/.lua/reilua"
        ],
        "Lua.diagnostics.globals": ["RL"]
      }
    }
  }
}

---

Method 3: Using Zed's LSP Configuration

Create a .zed/settings.json in your project: > Note There is a sample zed settings json file in the repo root (zed.sample.settings.json)

{
  "lsp": {
    "lua-language-server": {
      "settings": {
        "Lua.runtime.version": "Lua 5.4",
        "Lua.workspace.library": [
          "."
        ],
        "Lua.completion.enable": true,
        "Lua.completion.callSnippet": "Replace",
        "Lua.completion.displayContext": 3,
        "Lua.diagnostics.globals": [
          "RL"
        ],
        "Lua.hint.enable": true,
        "Lua.hint.paramName": "All",
        "Lua.hint.setType": true
      }
    }
  }
}

---

Verifying Setup

Create a test file test.lua:

function RL.init()
    -- Type "RL." and you should see autocomplete
    RL.SetWindowTitle("Test")  -- Should show documentation

    local color = RL.RED  -- Should autocomplete color constants

    -- Hover over functions to see documentation
    RL.DrawText("Hello", 10, 10, 20, color)
end

function RL.update(delta)
    -- 'delta' should show as number type
end

If autocomplete works, you should see:

---

Enhanced Features

Enable Inlay Hints

In Zed settings:

{
  "inlay_hints": {
    "enabled": true
  },
  "lsp": {
    "lua-language-server": {
      "settings": {
        "Lua.hint.enable": true,
        "Lua.hint.paramName": "All",
        "Lua.hint.setType": true,
        "Lua.hint.paramType": true
      }
    }
  }
}

This will show:

Disable Annoying Warnings

Add these to suppress common false positives:

{
  "lsp": {
    "lua-language-server": {
      "settings": {
        "Lua.diagnostics.disable": [
          "lowercase-global",
          "unused-local",
          "duplicate-set-field",
          "missing-fields",
          "undefined-field"
        ],
        "Lua.diagnostics.globals": ["RL"]
      }
    }
  }
}

Common warnings and what they mean:

> Note: The tools/ReiLua_API.lua file now uses type annotations instead of function definitions for callbacks to prevent duplicate warnings.

---

Troubleshooting

"duplicate-set-field" Error

Problem: Getting warnings like Duplicate field 'init'. (Lua Diagnostics. duplicate-set-field) Why: The tools/ReiLua_API.lua file previously defined callback functions as empty function definitions. When you define them in your main.lua, LSP sees it as redefining the same field. Solution: The latest tools/ReiLua_API.lua now uses type annotations instead: 
-- Old way (caused warnings)
function RL.init() end

-- New way (no warnings)
---@type fun()
RL.init = nil

Fix Steps: 1. Update tools/ReiLua_API.lua - Copy the latest version from the repository 2. Or add to diagnostics.disable in your configuration:

   {
     "diagnostics.disable": ["duplicate-set-field"]
   }

3. Restart Zed to reload the configuration

Benefits of the new approach:

---

Autocomplete Not Working

1. Restart Zed after configuration changes 2. Check LSP Status: Look for Lua Language Server in bottom-right status bar 3. Verify File Location: Ensure tools/ReiLua_API.lua is in the workspace 4. Check Console: Open Zed's log to see LSP errors

Performance Issues

If the language server is slow:

{
  "lsp": {
    "lua-language-server": {
      "settings": {
        "Lua.workspace.maxPreload": 2000,
        "Lua.workspace.preloadFileSize": 1000
      }
    }
  }
}

Missing Documentation

Ensure hover is enabled:

{
  "hover_popover_enabled": true
}

---

Advanced: Custom Annotations

You can extend tools/ReiLua_API.lua with your own game types:

---@class Player
---@field x number
---@field y number
---@field health number

---@class Enemy
---@field x number
---@field y number
---@field damage number

-- Your game globals
---@type Player
player = {}

---@type Enemy[]
enemies = {}

---

Keyboard Shortcuts in Zed

---

Additional Resources

---

Example Project Structure

my-reilua-game/
├── .luarc.json              # LuaLS configuration
├── .zed/
│   └── settings.json        # Zed-specific settings
├── tools/ReiLua_API.lua           # API definitions (copy from ReiLua)
├── main.lua                 # Your game entry point
├── player.lua
├── enemy.lua
└── assets/
    ├── sprites/
    └── sounds/

---

Quick Start Template

Save this as .luarc.json in your project:

{
  "runtime.version": "Lua 5.4",
  "completion.enable": true,
  "completion.callSnippet": "Replace",
  "diagnostics.globals": ["RL"],
  "diagnostics.disable": [
    "lowercase-global",
    "duplicate-set-field",
    "missing-fields"
  ],
  "workspace.checkThirdParty": false,
  "workspace.library": ["."],
  "hint.enable": true
}

Save this as .zed/settings.json:

{
  "lsp": {
    "lua-language-server": {
      "settings": {
        "Lua.hint.enable": true,
        "Lua.hint.paramName": "All",
        "Lua.hint.setType": true,
        "Lua.diagnostics.disable": [
          "lowercase-global",
          "duplicate-set-field",
          "missing-fields"
        ]
      }
    }
  },
  "inlay_hints": {
    "enabled": true
  }
}

Then copy tools/ReiLua_API.lua to your project root, and you're ready to go!

---

Happy Coding!

ReiLua Enhanced · indrajith.dev