Drawing on the canvas

Pen strokes, arrows and boxes over the circuit, on a layer of their own that the simulator never sees.

Opening the drawing tools

Press D, or the pen button in the canvas toolbar, or Draw in the toolbar's more menu. A small strip appears under the toolbar with everything the layer has: Pen, Arrow, Box, Erase, five colors, two widths, Clear drawings and Done.

While a tool is on, the pointer draws instead of selecting. Dragging over a part leaves a mark across it rather than moving it, and dragging over the board draws rather than pans. Getting around does not change: the middle button, the right button and holding Space all still pan, and the wheel still zooms.

Escape puts the pen away and gives the pointer back, and so does Done or the Draw button again.

The three marks

• Pen follows your hand. What is stored is not every sample the pointer sent: the run is thinned and then drawn through its own midpoints with curves, so a stroke is a smooth line rather than the tremor of the pointer that made it.
• Arrow is a drag from tail to head. The head is drawn, not filled, so it grows with the width.
• Box is a drag between two opposite corners, drawn as four edges with nothing inside them.

Ink, red, blue, green and amber, thin or thick. The colors are chosen per theme rather than stored as a fixed value, so a project drawn on the dark board still reads on the light one and the other way around.

Moving, selecting and erasing

With the pen away, a mark behaves like anything else on the canvas. Click one to select it. Click on the line, not in the space it encloses, so a click inside a box belongs to the circuit under it. Drag to move it, shift-drag a marquee to catch several, and Delete to remove them. It all goes on the undo stack, it all copies and pastes with Ctrl/Cmd+C and V, and in a room everybody sees the same marks as they are made.

Erase on the strip takes away the mark you click on, one at a time. Clear drawings empties the whole layer in one go, which one Ctrl/Cmd+Z puts back.

The Drawings row in the layers panel

Press L for the layers panel and the drawing layer has a row of its own, under Notes. Hide it to see the circuit without the annotation, dim it to push it back, or lock it so a stray drag cannot move a mark you are happy with. Like the rest of that panel this is how you are looking at the project, not part of it: it is kept in this browser and never travels in the diagram or a share link.

Drawings and export

A PNG or SVG export leaves the drawing layer out by default. A picture of a circuit is the circuit, and the arrows somebody drew while explaining it are working notes. When you do want them (a worksheet with "start here" written on it, a diagram for a lesson), tick Include drawings in the share sheet before you download, and both formats carry the marks.

The marks are never electrical. They live beside the parts in the document rather than among them, so a board covered in arrows builds exactly the same netlist as a bare one and runs exactly the same way.