linepointqgisvector
I'm trying to do something very simple, to create points and lines in a new vector layer. With the 'Add Feature' button I can create polygons, but I can't find any tool to create points and/or lines. Is there a way to do so?
I've tried all of this tools and can't seem to find it:
NOTE the plugin referenced below is no longer maintained. The QGIS plugin site suggests using the CAD Digitize plugin instead (as of January 2018).
There's the Rectangles Ovals Digitizing plugin that does just that and the shapes you create are saved in a layer (start editing that layer first).
It allows you to draw Rectangles, Squares, Ovals and Circles.
But I'm not sure about a plugin for arrows and other diagram type object. Those can be added in the Print Composer Layout, there is a separate toolbar for that.
I've had a similar problem and I think it's due to the way that QGIS calculates the number of points when using density. It is rounding the density * polygon area for each polygon. So if that value is < 0.5 for any of your polygons, QGIS will round this to 0 and then you'll get a divide by 0 error.
For example:
Say you choose a density of 0.01. If you have a polygon with an area of 49, then 49 * 0.01 = 0.49. QGIS will then round this down to 0.
The solution for me was to remove the polygons that were smaller than this, then re-add them afterwards.
Best Answer
Go to layer menu:
Create new layer:
Select point (or line) type:
You'll be able to add points, same scenario for lines: