SDL2 for Alusus

[العربية]

SDL2 bindings for the Alusus Programming Language, providing comprehensive access to SDL2 graphics, audio, and input functionality with full Arabic language support.

Features

• Graphics: Window creation, rendering, textures, surfaces, and 2D drawing primitives
• Audio: Music playback and sound effects via SDL2_mixer
• Input: Keyboard, mouse, and joystick/gamepad support
• Image Loading: PNG, JPG, TIF, and WEBP format support via SDL2_image
• Text Rendering: Advanced text rendering with HarfBuzz integration for proper Arabic text shaping (Linux only)
• Bilingual API: Full Arabic language bindings alongside English API
• Cross-Platform: Support for Linux and macOS

Components

This library provides bindings for:

• SDL2: Core graphics, windowing, and event handling
• SDL2_image: Image file loading (PNG, JPG, WEBP, TIF)
• SDL2_mixer: Audio playback (music and sound effects)
• SDL2_gfx: Advanced 2D drawing primitives
• HarfBuzz Extension: Custom text rendering with proper Arabic text shaping

Requirements

System Dependencies

Linux

sudo apt-get install libsdl2-2.0-0 libsdl2-image-2.0-0 libsdl2-mixer-2.0-0 libsdl2-gfx-1.0-0

macOS

brew install sdl2 sdl2_image sdl2_mixer sdl2_gfx

Alusus

• Alusus compiler version 0.8 or later
• Installation instructions available at alusus.org

Installation

Using Alusus Package Manager (APM):

import "Apm.alusus";
Apm.importPackage("Alusus/Sdl2@0.1", "Sdl.alusus");

Usage

Basic Example (English)

import "Srl/Console.alusus";
import "Apm.alusus";
Apm.importPackage("Alusus/Sdl2@0.1", "Sdl.alusus");

// Initialize SDL
Sdl.init(Sdl.INIT_VIDEO);

// Create window
def window: ptr[Sdl.Window] = Sdl.Window.create("My Game", 0, 0, 800, 600, 0);

// Create renderer
def renderer: ptr[Sdl.Renderer] = Sdl.Renderer.create(window, -1, Sdl.Renderer.Flags.ACCELERATED);

// Main loop
def running: Bool = true;
def event: Sdl.Event;

while running {
    // Handle events
    while Sdl.pollEvent(event~ptr) != 0 {
        if event.eventType == Sdl.Event.QUIT {
            running = false;
        }
    }

    // Clear screen
    Sdl.Renderer.setDrawColor(renderer, 0, 0, 0, 255);
    Sdl.Renderer.clear(renderer);

    // Present frame
    Sdl.Renderer.present(renderer);
}

Loading and Displaying Images

// Initialize image subsystem
Sdl.Img.init(Sdl.Img.INIT_PNG);

// Load texture
def texture: ptr[Sdl.Texture] = Sdl.Img.loadTexture(renderer, "image.png");

// Render texture
def destRect: Sdl.Rect(100, 100, 200, 200);
Sdl.Renderer.copy(renderer, texture, 0, destRect~ptr);

Playing Audio

// Initialize audio
Sdl.Audio.init(44100, Sdl.Audio.Format.DEFAULT, 2, 2048);

// Load and play music
def music: ptr[Sdl.Audio.Music] = Sdl.Audio.loadMusic("song.ogg");
Sdl.Audio.play(music, -1); // -1 = loop forever

// Load and play sound effect
def sound: ptr[Sdl.Audio.Sound] = Sdl.Audio.loadWav("effect.wav");
Sdl.Audio.play(-1, sound, 0, -1); // Play on first available channel

Text Rendering (Linux only)

// Initialize text subsystem
Sdl.Text.init();

// Open font
def font: ptr[Sdl.Text.Font] = Sdl.Text.openFont("font.ttf", 24);

// Render text
def color: Sdl.Color(255, 255, 255, 255);
Sdl.Text.renderText("Hello, World!", color~ptr, font, 0, 100, 100, renderer);

// For Arabic text with proper shaping
Sdl.Text.renderText("مرحبا بالعالم", color~ptr, font, 1, 100, 100, renderer);

Keyboard Input

// Get keyboard state
def keyStates: ptr[array[Word[8]]] = Sdl.Keyboard.getState(0);

// Check specific keys
if keyStates~cnt(Sdl.Keyboard.ScanCode.SPACE) != 0 {
    Console.print("Space pressed\n");
}

Mouse Input

// Get mouse state
def x: Int;
def y: Int;
def buttons: Word = Sdl.Mouse.getState(x~ptr, y~ptr);

Examples

The Examples/ directory contains sample programs:

• ship.alusus: Complete game demo with graphics, audio, text rendering, and keyboard input
• joystick_test.alusus: Joystick/gamepad input demonstration

To run an example:

alusus Examples/ship.alusus

Platform-Specific Notes

Linux

• Full functionality including HarfBuzz text rendering
• Text rendering supports both LTR (English) and RTL (Arabic) scripts

macOS

• Graphics, audio, and input fully supported
• HarfBuzz text rendering is disabled on macOS

API Reference

Initialization Flags

• Sdl.INIT_VIDEO: Initialize video subsystem
• Sdl.INIT_AUDIO: Initialize audio subsystem
• Sdl.INIT_JOYSTICK: Initialize joystick subsystem

Event Types

• Sdl.Event.QUIT: Window close event
• Sdl.Event.KEY_DOWN: Key press event
• Sdl.Event.KEY_UP: Key release event
• Sdl.Event.MOUSEMOTION: Mouse movement
• Sdl.Event.MOUSEBUTTONDOWN: Mouse button press
• Sdl.Event.MOUSEBUTTONUP: Mouse button release

Renderer Flags

• Sdl.Renderer.Flags.SOFTWARE: Software rendering
• Sdl.Renderer.Flags.ACCELERATED: Hardware-accelerated rendering

Blend Modes

• Sdl.BlendMode.NONE: No blending
• Sdl.BlendMode.BLEND: Alpha blending
• Sdl.BlendMode.ADD: Additive blending
• Sdl.BlendMode.MOD: Modulative blending

License

This library is licensed under the GNU Lesser General Public License (LGPL). See the COPYING and COPYING.LESSER files for details.

Contributing

Contributions are welcome! Please submit issues and pull requests on the project repository.

Links

• Alusus Website
• SDL2 Documentation
• Alusus Documentation