I want to draw a free-hand polygon, to enclose certain portions of my diagram so I can identify them as being part of Phase I development, for example. Is there a polygon tool in draw.io?
Start by adding the polygon shape to your drawing. The polygon shape is within the "Basic" shapes group. You may need to bring the "Basic" shapes group into view from the "View" > "Shapes..." menu.
Next, select your polygon and click "Edit Style". There you will see something like:
Add/Remove additional points to the polyCoords array and click on Apply. No need to worry about getting the coordinates correct -- we'll move them around in the next step. Just keep them within the boundary of your shape (from 0.0 to 1.0). Click Apply.
Finally, move your points around on the drawing canvas.
Unfortunately, at present time (and since a long time) there is no easy solution. If you really need to draw a filled polygon, the only solution that I could find is to represent it as a "patchwork" of simple shape (triangles, rectangles, etc.). More precisely, for each of the shapes which will compose te patchwork, you can:
- define the correct size, and the correct rotation by adjusting the parameter [Angle] of the onglet [Arrange]; this is the most time-consuming step,
- remove the border, fill the shape with the color you want, and send it to the back,
If you take time, you can reasonably cover simple polygons by using this technique.