Compass & Ruler: Interactive Geometry Tool

Welcome to Compass & Ruler, Your digital canvas for creating Euclidean geometric constructions with precision and ease. This free application works directly in your browser, allowing you to explore mathematical concepts, theorems, and figures without the need to install additional software.

User Guide and Tools

Our sidebar toolbar is designed to be intuitive. Here's how to use each function to create perfect builds:

1. Basic Tools

  • 🖐️ Select and Move (Select & Grab): Your primary tool. Use it to select existing objects (they'll light up when you hover over them) or drag the canvas to move around your workspace. Selecting an object will open the panel of Properties where you can change colors or delete elements.

  • • Period: Click anywhere on the canvas to create a free point. If you click at the intersection of two lines or circles, the point will magnetically snap to the exact intersection.

  • 🔤 Label: Click on an existing point to automatically assign it a letter (A, B, C...). Useful for mathematical proofs.

2. Lines and Strokes

  • 📏 Segment: Draw a finite line connecting two points.

  • ➖ Infinite Straight Line: Create a line that extends infinitely in both directions passing through two points.

  • 🔃 Parallel: Two-step construction:

    1. Select an existing line or segment as a reference.

    2. Click on a point where you want the new parallel line to pass.

  • ➕ Perpendicular: Two-step construction:

    1. Select a reference line or segment.

    2. Click on a point to draw a line that crosses at exactly 90°.

3. Figures

  • ⭕ Circle: Draw perfect circles. Click once to define the center and again to define the radio.

Advanced Features

  • 🎨 Personalization: Select any shape to change its color, thickness or line style (solid, dotted, or dashed). Ideal for differentiating auxiliary strokes!

  • 🌓 Light and Dark Theme: Use the button in the upper right corner to switch between modes, protecting your eyesight in low-light environments.

  • Undo and Redo: Did you make a mistake? No problem. Use the menu arrows or keyboard shortcuts (Ctrl+Z, Ctrl+Y) to correct your steps.

  • 🔍 Zoom and Full Screen: Zoom in to see the finest details or use full-screen mode for an immersive experience on digital whiteboards or tablets.

This tool is ideal for elementary, middle, and high school students who want to practice plane geometry, as well as for teachers looking for interactive teaching resources.