r.cost
r.cost.raster - Creates a raster layer of cumulative cost of moving across a raster layer whose cell values represent cost.
Raster (r.*)
ParameterRaster|input|Unit cost layer|False
ParameterRaster|start_raster|Name of starting raster points map|False
ParameterBoolean|-k|Use the 'Knight's move'; slower, but more accurate|False
ParameterBoolean|-n|Keep null values in output raster layer|True
ParameterNumber|max_cost|Maximum cumulative cost|0|None|0
ParameterNumber|null_cost|Cost assigned to null cells. By default, null cells are excluded|None|None|0
ParameterNumber|memory|Maximum memory to be used in MB|0|None|300
OutputRaster|output|Cumulative cost