Point2Point

A cross-platform screen pixel measurement tool that allows you to measure distances between any two points on your screen and displays the result in all HTML/CSS supported units.

Features

• Screen-wide Measurement: Measure pixels anywhere on your screen (browser, desktop, any application)
• Multi-Monitor Support: Select which monitor to capture on multi-monitor setups
• All HTML/CSS Units: Instantly converts pixel measurements to all CSS length units
• Live Preview: See distance in real-time as you move the cursor
• Configurable Settings: Adjust DPI and base font size for accurate conversions
• Resizable Window: Customize the application window size to your preference

Supported Platforms

Operating Systems

OS	Status	Notes
Linux	Fully Supported	Primary development platform
macOS	Should Work	Requires screenshot tool (e.g., screencapture)
Windows	Not Tested	May require modifications

Display Protocols

Protocol	Status	Screenshot Tool	Notes
Wayland (GNOME)	Fully Supported	gnome-screenshot	Recommended for GNOME desktop
Wayland (wlroots)	Supported	grim	For Sway, Hyprland, etc.
X11	Fully Supported	scrot, gnome-screenshot	Works with any X11 desktop
XWayland	Supported	gnome-screenshot, grim	Hybrid environments

Supported CSS Units

Unit	Description
px	Pixels (absolute)
pt	Points (1pt = 1/72 inch)
pc	Picas (1pc = 12pt)
em	Relative to element font-size
rem	Relative to root font-size
%	Percentage of screen width
vw	1% of viewport width
vh	1% of viewport height
vmin	1% of smaller viewport dimension
vmax	1% of larger viewport dimension
cm	Centimeters
mm	Millimeters
in	Inches
Q	Quarter-millimeters
ch	Width of "0" character
ex	Height of "x" character

Requirements

Python Dependencies

• Python 3.6+
• Tkinter (usually included with Python)
• Pillow (pip install pillow)

Screenshot Tools (at least one required)

For Wayland (GNOME):

# Fedora/RHEL
sudo dnf install gnome-screenshot

# Ubuntu/Debian
sudo apt install gnome-screenshot

For Wayland (wlroots-based compositors):

# Fedora/RHEL
sudo dnf install grim

# Ubuntu/Debian
sudo apt install grim

# Arch
sudo pacman -S grim

For X11:

# Fedora/RHEL
sudo dnf install scrot

# Ubuntu/Debian
sudo apt install scrot

# Arch
sudo pacman -S scrot

Installation

From Source

# Clone the repository
git clone https://github.com/tatlilimon/point2point.git
cd point2point

# Install Python dependencies
pip install pillow

# Make executable (optional)
chmod +x pixel_measure.py

# Create a command alias (optional)
mkdir -p ~/.local/bin
ln -sf $(pwd)/pixel_measure.py ~/.local/bin/point2point

# Add to PATH if needed (add to ~/.bashrc or ~/.zshrc)
export PATH="$HOME/.local/bin:$PATH"

Quick Start

python3 pixel_measure.py

Or if you created the alias:

point2point

Usage

1. Launch the application
2. Click "Start Measuring"
3. If you have multiple monitors, select which one to capture
4. Click the first point on the screenshot
5. Move cursor to see live distance preview
6. Click the second point
7. View measurements in all CSS units

Press ESC at any time to cancel measurement.

Settings

Setting	Default	Description
Screen DPI	96	Adjust for accurate physical unit conversions (cm, mm, in)
Base font size	16px	Reference font size for em/rem calculations

Multi-Monitor Setup

Point2Point automatically detects all connected monitors and their positions. When you click "Start Measuring":

1. A dialog appears listing all detected monitors with their:
   • Name (e.g., DP-1, HDMI-1, eDP-1)
   • Resolution (e.g., 1920x1080)
   • Position (x, y coordinates)
2. Select a specific monitor or "All Monitors (Full Desktop)"
3. The screenshot will be cropped to the selected monitor

Troubleshooting

Screenshot appears gray/empty

• Ensure you have a screenshot tool installed (gnome-screenshot, grim, or scrot)
• On Wayland, gnome-screenshot is recommended for GNOME desktop
• Check terminal output for error messages

Monitor detection not working

• Install xrandr (usually pre-installed on most Linux systems)
• For wlroots-based compositors, install wlr-randr

Window doesn't appear fullscreen

• This may happen on some Wayland compositors
• Try using "All Monitors" option instead of a specific monitor

Contributing

Contributions are welcome! Please feel free to submit a Pull Request.

License

GPL-3.0 license