Working under QGIS 3.16.4 and using the Modeler, I would like to create buffers for a polygons layer.
The polygons layer includes the buffer size as an attribute (e.g.
"BUFFER_M") resulting from the field calculator (a previous step in the model).
Although I specified the polygons layer as the Input layer (Using algorithm output), there is no fields available (
NULL) in the Expression Dialog.
I tried to fix the Distance with the expected BUFFER_M field as following: Pre-calculated Value >
"BUFFER_M" in the Expression Dialog with no success.
All other steps in the model worked well but the buffers layer was generated with a Distance default value of 10,00 m.
Any ideas on how to specify the buffer size (Distance parameter) based on a field attribute of the input layer (vector layer)?
NB: the same problem when done manually as well (generated buffer of 10,00 m), however in this case the
"BUFFER_M" field was available in the Expression Dialog.