Is there a way to convert 2D features to "3D" features in QGIS? I know there is a way to do this in ArcMap by using an attribute value in the attribute table, but I am looking to do this with shapefiles in QGIS.
You can use the v.to.3d module in the GRASS toolkit (installed with QGIS) to do 2d to 3d layer transformation:
v.to.3d - Performs transformation of 2D vector features to 3D.
QGIS 3 has 3D support now. Open 3D Map window via "View > New 3D Map View" and set any filed as height and/or extrusion value.
This post helps you out.
QGIS 2.14 version does convert 2D to 3D features.
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