How to digitize rectangles with snapping in QGIS?

Question

Trying to digitize a floor plan for a building (just need polygons for each room) in QGIS (shapefile layer). I started just trying to draw the features, but want to align polygons so that there is no gap or overlap. That led me to the Snapping features which helped a lot. But having trouble making sure my rectangles have 90 degree corners.

Then I discovered the rectangles ovals digitizing tool which solves that problem. Unfortunately--it seems to ignore the "snapping" that I got when just drawing features node to node. Is there a way to get both snapping and rectangles in QGIS?

Answer 1

I have had similar issues. One approach I have done is to use the CadInput tool. This tool allows you to draw vectors based on distances, angles, etc. which ensures that when you enter in a new vector, they snap to the point you want. It works with the snapping tolerance that is native within QGIS.

https://vimeo.com/85052231

Answer 2

Thanks very much for pointing me towards CadInput. This got me on a continued hunt and I ended up using another plugin called CADDigitize [ https://hub.qgis.org/projects/caddigitize ]. I was originally confused because this plugin does not provide visual feedback of the snapping. But if you hold down the control key, it will snap the actual nodes when you click to place them. I also like it's ability to do rectangle by extant or by 3 points. I use extant to draw my first rectangle, then use 3 points with snap on the first two to draw another rectangle lined up with the first.