Put a ruler on the canvas and draw the way you would on a real board

How the virtual ruler works

1. Press R or select the ruler tool.
2. Drag the ruler body to position it.
3. Use the round handle to rotate it to the required angle.
4. Write near the top edge; the pen snaps to the ruler for a straight stroke.

When the line tool is faster

Press L for a one-off straight segment without leaving a ruler on screen. Hold Shift while drawing to snap the line to useful constraints. Use it for axes, vectors, construction guides and diagram edges.

Made for visible reasoning

The ruler is most useful when students need to see the construction, not only the result: a geometry proof, vector diagram, coordinate graph, free-body diagram or annotated exam question.

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