In QGIS, I'm trying to draw some polygons (mostly rectangles) on a grid, with neat 90-degree right angles and such. All the polygons should be parallel or perpendicular to each other.
The problem is that the city I'm working on top of, Chicago, skews a little bit off a proper north-south line. For example, in the image below, Grant Park's field (yellow rectangle) is off just a bit from the red north-south line generated by Advanced Digitizing (and the red rectangle built from that line). Thus, anything I create off that red line won't match up with the park's grid.
Can I somehow "rotate" or "offset" the tool such that every line snaps to the yellow rectangle's lines, instead of compass north? If I add a bunch more red rectangles, their lines should all be parallel and perpendicular with the yellow one over Grant Park.
I tried rotating the entire QGIS canvas, but Advanced Digitizing still just points north-south. Or, if not through Advanced Digitizing, can I create my own guide/grid lines to snap other polygons to? Not really sure the proper way to do this.