: drag to move around the canvas (shortcut: hold Space down).
: click to select an existing shape and edit its properties.
: click to draw a line. Each click determines the coordinates of an end point.
: click to draw a circle. The first click determines the coordinates of the center; the second click determines the radii. A circle can be edited into an ellipse when selected.
: click to draw a polygon. Each click creates a corner. A polygons is a closed shape. The first and last click must occur at the same coordinates.
: click and drag to draw cubic Bezier curves (see here for an introduction). Each click creates an anchor and each drag creates one or a pair of handles. During drawing, when Shift is pressed, the most recently created handle is reset to the the most recently created anchor. Curves can be closed or open: when drawing curves, clicking on the starting anchor closes it; pressing Enter finishes and creates an open curve.
: insert texts (supports inline math).
: undo (shortcuts: Ctrl-Z / Cmd-Z).
: redo (shortcuts: Ctrl-Y / Cmd-Y / Shift-Cmd-Z).
: show TikZ code.
: copy a url to clipboard that allows future access to the current drawing (shortcuts: Ctrl-S / Cmd-S).
When an existing shape is selected, a property box shows up. Properties of shapes can be changed there. Additionally, two buttons appear
-
: toggle snapping. When it is checked, shapes and points can only move by multiples of half of the size of a grid cell. Snapping will be turned on automatically when drawing new shapes. -
: delete selected shape (shortcuts: DELETE / BACKSPACE).
On the canvas, a shadow and some control points will appear around the selected shape. Move the selected shape around by dragging the shadow; change its shape by dragging the points.
[Sep.10, 2021] When a shape is selected, you can press Ctrl-C / Cmd-C to copy it and then Ctrl-V / Cmd-V to paste a copy to the current pointer location.
Hold SPACE down: set tool to .
Ctrl-Z / Cmd-Z: .
Ctrl-Y / Cmd-Y / Shift-Cmd-Z: .
Ctrl-S / Cmd-S: .
Ctrl-C / Cmd-C : copy selected shape. [Sep.10, 2021]
Ctrl-V / Cmd-V : paste copied shape to pointer location. [Sep.10, 2021]
Esc: abort drawing process (delete shapes that are being created, like unclosed polygon, unsubmitted text input, etc).
Enter: finish curve drawing (creates an open curve).
Shift: reset last handle to its corresponding anchor when drawing curves.
DELETE / BACKSPACE: 
.
Mouse wheel: zoom.