GUI-Desktop Enviroment

NØNOS includes a graphical desktop environment.

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Architecture

┌─────────────────────────────────────────────────────────────────┐
│                    DESKTOP ENVIRONMENT                          │
├─────────────────────────────────────────────────────────────────┤
│                                                                 │
│  ┌─────────────┐  ┌─────────────┐  ┌─────────────────────────┐  │
│  │   Taskbar   │  │ System Tray │  │     Clock Widget        │  │
│  └─────────────┘  └─────────────┘  └─────────────────────────┘  │
│                                                                 │
│  ┌───────────────────────────────────────────────────────────┐  │
│  │                                                           │  │
│  │                    WINDOW COMPOSITOR                      │  │
│  │                                                           │  │
│  │   ┌─────────────────┐     ┌─────────────────┐             │  │
│  │   │    Terminal     │     │   Application   │             │  │
│  │   │                 │     │                 │             │  │
│  │   └─────────────────┘     └─────────────────┘             │  │
│  │                                                           │  │
│  └───────────────────────────────────────────────────────────┘  │
│                                                                 │
└─────────────────────────────────────────────────────────────────┘
                              │
                              ▼
┌─────────────────────────────────────────────────────────────────┐
│                      FRAMEBUFFER DRIVER                         │
│                   (UEFI GOP / Direct FB)                        │
└─────────────────────────────────────────────────────────────────┘

---

Components

Window Manager

Manages window lifecycle:

Window {
    id: u32,              // Unique identifier
    title: String,        // Window title
    x: i32, y: i32,       // Position
    width: u32,           // Width in pixels
    height: u32,          // Height in pixels
    visible: bool,        // Visibility state
    framebuffer: Vec<u32>, // RGBA pixel data
    process_id: u32,      // Owning process
}

Window Compositor

Composites windows to screen:

• Dirty region tracking

• Z-order management

• Window occlusion

• Double buffering

Taskbar

Shows running applications:

• Application icons

• Window titles

• Quick launch

• System buttons

System Tray

System indicators:

• Network status

• Battery (if applicable)

• Notifications

• Quick settings

Clock Widget

Time display:

• 24-hour or 12-hour format

• Optional seconds display

• Date display

---

Framebuffer

Specifications

Parameter	Value
Max Resolution	1920 × 1080
Pixel Format	RGBA (32-bit)
Color Depth	8 bits per channel
Max Pixels	~4 million
Min Buffer	4 KB

---

Memory Layout

Pixel at (x, y):
  offset = (y * stride + x) * 4

  byte[offset + 0] = Blue
  byte[offset + 1] = Green
  byte[offset + 2] = Red
  byte[offset + 3] = Alpha

---

Input Handling

Keyboard

• PS/2 keyboard support

• USB keyboard (XHCI)

• Scancode to keycode translation

• Modifier key tracking (Shift, Ctrl, Alt)

Mouse

• PS/2 mouse support

• USB mouse (XHCI)

• Absolute and relative positioning

• Button state tracking

---

Event System

Event Types

enum GuiEvent {
    WindowCreated { id: u32 },
    WindowDestroyed { id: u32 },
    WindowResized { id: u32, width: u32, height: u32 },
    WindowMoved { id: u32, x: i32, y: i32 },
    WindowFocused { id: u32 },
    KeyPressed { keycode: u32, modifiers: u32 },
    KeyReleased { keycode: u32 },
    MouseMoved { x: i32, y: i32 },
    MouseButton { button: u32, pressed: bool },
}

Event Flow

Hardware Interrupt
       │
       ▼
   Driver Layer
       │
       ▼
   Event Queue
       │
       ▼
 Window Manager
       │
       ▼
  Active Window

---

Terminal

Built-in terminal emulator:

Features

• VT100/ANSI escape codes

• Scrollback buffer

• Copy/paste

• Configurable colors

• Multiple fonts

Shell Commands

# System information
sysinfo

# Memory status
memstat

# Process list
ps

# Clear screen
clear

# Help
help

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Graphics API

Drawing Primitives

// Fill rectangle
draw_rect(x, y, width, height, color);

// Draw line
draw_line(x1, y1, x2, y2, color);

// Draw text
draw_text(x, y, text, font, color);

// Blit image
blit(src, dst, x, y);

Color Format

// RGBA color
let red   = 0xFF0000FF;  // Red, full alpha
let green = 0x00FF00FF;  // Green, full alpha
let blue  = 0x0000FFFF;  // Blue, full alpha
let trans = 0xFFFFFF00;  // White, transparent

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Resolution Support

Resolution	Status
640 × 480	Supported
800 × 600	Supported
1024 × 768	Supported
1280 × 720	Supported
1920 × 1080	Supported
Higher	Limited by VRAM

---

Performance

Operation	Time
Window create	~1 ms
Window destroy	~0.5 ms
Full redraw	~16 ms (60 FPS)
Partial redraw	~2 ms
Input event	~0.1 ms

---

Themes

Default Theme

Element	Color
Background	Dark gray (#2D2D2D)
Window title	Blue (#3498DB)
Active border	Light blue (#5DADE2)
Inactive border	Gray (#7F8C8D)
Text	White (#FFFFFF)

---

Configuration

Display settings in boot config:

# target/esp/EFI/nonos/boot.cfg

resolution=1920x1080
refresh=60
vsync=true

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Limitations

Current limitations (active development):

• Single monitor only

• No hardware acceleration (software rendering)

• Basic window decorations

• Limited font support

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Future Plans

• Multi-monitor support

• GPU acceleration (Vulkan/OpenGL)

• Wayland-compatible protocol

• Theme customization

• Widget toolkit