DrawThatThing

A cross-platform desktop application that converts images into automated mouse drag actions, allowing you to "replay" an image as a drawing.

Features

• Image Parsing: Load images and analyze pixel data using multiple parsing algorithms
• Mouse Automation: Convert parsed image data to mouse drag sequences and replay them
• Color Management: Define custom color palettes, pick colors from screen, mark background colors
• Plugin Architecture: Extensible bitmap readers and brush changers
• Global Hotkeys: System-wide keyboard shortcuts for quick actions
• Live Preview: See how the image will be drawn before executing

Project Structure

DrawThatThing/
├── DrawThatThing.Avalonia/         # Main Avalonia UI application
├── DrawThatThing.Core/             # Platform-agnostic core library
├── DrawThatThing.Platform/         # Platform abstraction interfaces
├── DrawThatThing.Platform.Windows/ # Windows-specific implementations
├── DrawThatThing.Platform.macOS/   # macOS-specific implementations
├── DrawThatThing.Platform.Linux/   # Linux-specific implementations
├── DrawThatThing.sln               # Solution file
├── build.sh                        # Build script for Linux/macOS
└── build.cmd                       # Build script for Windows

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Requirements

Platform	.NET SDK	Additional Requirements
All	.NET 8.0 SDK or later	-
Windows	-	None (Win32 APIs included)
macOS	-	Accessibility permissions (System Preferences → Security & Privacy → Privacy → Accessibility)
Linux	-	X11, libXtst (XTest extension)

Installing .NET 8 SDK

Windows

# Using winget
winget install Microsoft.DotNet.SDK.8

# Or download from https://dotnet.microsoft.com/download/dotnet/8.0

macOS

# Using Homebrew
brew install --cask dotnet-sdk

# Or download from https://dotnet.microsoft.com/download/dotnet/8.0

Linux (Ubuntu/Debian)

# Add Microsoft package repository
wget https://packages.microsoft.com/config/ubuntu/22.04/packages-microsoft-prod.deb -O packages-microsoft-prod.deb
sudo dpkg -i packages-microsoft-prod.deb
rm packages-microsoft-prod.deb

# Install .NET SDK
sudo apt-get update
sudo apt-get install -y dotnet-sdk-8.0

# Install X11 dependencies for mouse automation
sudo apt-get install -y libx11-dev libxtst-dev

Linux (Fedora)

sudo dnf install dotnet-sdk-8.0
sudo dnf install libX11-devel libXtst-devel

Linux (Arch)

sudo pacman -S dotnet-sdk
sudo pacman -S libx11 libxtst

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Building from Source

# Restore dependencies
dotnet restore DrawThatThing.sln

# Build in Debug mode
dotnet build DrawThatThing.sln

# Build in Release mode
dotnet build DrawThatThing.sln -c Release

Or use the provided build scripts:

# Linux/macOS
./build.sh

# Windows
build.cmd

Running the Application

dotnet run --project DrawThatThing.Avalonia/DrawThatThing.Avalonia.csproj

Publishing Self-Contained Executables

Create standalone executables that don't require .NET to be installed:

Windows (x64)

dotnet publish DrawThatThing.Avalonia -c Release -r win-x64 --self-contained -o publish/win-x64

Windows (ARM64)

dotnet publish DrawThatThing.Avalonia -c Release -r win-arm64 --self-contained -o publish/win-arm64

macOS (Intel)

dotnet publish DrawThatThing.Avalonia -c Release -r osx-x64 --self-contained -o publish/osx-x64

macOS (Apple Silicon)

dotnet publish DrawThatThing.Avalonia -c Release -r osx-arm64 --self-contained -o publish/osx-arm64

Linux (x64)

dotnet publish DrawThatThing.Avalonia -c Release -r linux-x64 --self-contained -o publish/linux-x64

Linux (ARM64)

dotnet publish DrawThatThing.Avalonia -c Release -r linux-arm64 --self-contained -o publish/linux-arm64

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Platform-Specific Notes

Windows

No additional configuration required. The application uses Win32 APIs for:

• Mouse control (user32.dll - SetCursorPos, mouse_event)
• Global hotkeys (user32.dll - RegisterHotKey)
• Screen capture (gdi32.dll - BitBlt)

macOS

Important: You must grant Accessibility permissions for mouse automation to work.

1. Open System Preferences (or System Settings on macOS Ventura+)
2. Go to Security & Privacy → Privacy → Accessibility
3. Click the lock icon to make changes
4. Add DrawThatThing to the list and enable it

The application uses:

• CoreGraphics framework for mouse control (CGEventCreateMouseEvent, CGEventPost)
• Carbon framework for global hotkeys (RegisterEventHotKey)
• CoreGraphics for screen capture (CGWindowListCreateImage)

Linux

Requires X11 and the XTest extension. Wayland is not currently supported for mouse automation.

Check if XTest is available:

xdpyinfo | grep -i xtest

Install dependencies:

# Ubuntu/Debian
sudo apt-get install libx11-6 libxtst6

# Fedora
sudo dnf install libX11 libXtst

# Arch
sudo pacman -S libx11 libxtst

For Wayland users: You may need to run the application under XWayland or switch to an X11 session for full functionality.

The application uses:

• X11 for mouse control (XTestFakeMotionEvent, XTestFakeButtonEvent)
• X11 for global hotkeys (XGrabKey)
• X11 for screen capture (XGetImage)

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Global Hotkeys

Hotkey	Action
Shift+Alt+C	Stop playback
Shift+Alt+S	Capture current mouse position
Shift+Alt+A	Add color at current cursor position
Shift+Alt+D	Toggle debug panel
Shift+Alt+Q	Add debug point

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Troubleshooting

Mouse automation not working

Windows: Run the application as Administrator if mouse events are being blocked.

macOS: Ensure Accessibility permissions are granted (see macOS notes above).

Linux:

• Verify XTest extension is installed: xdpyinfo | grep -i xtest
• Ensure you're running under X11, not pure Wayland

Application won't start

All platforms: Verify .NET 8 SDK is installed: dotnet --version

Linux: Install missing dependencies:

sudo apt-get install libicu-dev libssl-dev

Hotkeys not responding

Windows: Another application may have registered the same hotkeys.

macOS: Grant Accessibility permissions and restart the application.

Linux: Ensure no other application is grabbing those key combinations.

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Links

• Project Page: http://egeozcan.github.com/DrawThatThing
• Issues: https://github.com/egeozcan/DrawThatThing/issues

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License

This project is licensed under the GPL-3.0 License - see the LICENSE.txt file for details.