r.resamp.interp: implement parallelization with OpenMP (#1771)

raster/r.resamp.interp/Makefile

@@ -2,8 +2,9 @@ MODULE_TOPDIR = ../..
 
 PGM = r.resamp.interp
 
-LIBES = $(RASTERLIB) $(GISLIB) $(MATHLIB)
+LIBES = $(RASTERLIB) $(GISLIB) $(MATHLIB) $(OMPLIB)
 DEPENDENCIES = $(RASTERDEP) $(GISDEP)
+EXTRA_CFLAGS = $(OMPCFLAGS)
 
 include $(MODULE_TOPDIR)/include/Make/Module.make
 

raster/r.resamp.interp/benchmark/benchmark_r_resamp_interp.py

@@ -0,0 +1,57 @@
+"""Benchmarking of r.resamp.interp
+
+@author Aaron Saw Min Sern
+"""
+
+from grass.exceptions import CalledModuleError
+from grass.pygrass.modules import Module
+from subprocess import DEVNULL
+
+import grass.benchmark as bm
+
+
+def main():
+    results = []
+
+    # Users can add more or modify existing reference maps
+    benchmark(7071, "r.resamp.interp_50M", results)
+    benchmark(14142, "r.resamp.interp_200M", results)
+    benchmark(10000, "r.resamp.interp_100M", results)
+    benchmark(20000, "r.resamp.interp_400M", results)
+
+    bm.nprocs_plot(results)
+
+
+def benchmark(size, label, results):
+    reference = "r_resamp_interp_reference_map"
+    output = "benchmark_r_resamp_interp"
+
+    generate_map(rows=size, cols=size, fname=reference)
+    module = Module(
+        "r.resamp.interp",
+        input=reference,
+        output=output,
+        method="lanczos",
+        memory=500,
+        run_=False,
+        stdout_=DEVNULL,
+        overwrite=True,
+    )
+    results.append(bm.benchmark_nprocs(module, label=label, max_nprocs=16, repeat=3))
+    Module("g.remove", quiet=True, flags="f", type="raster", name=reference)
+    Module("g.remove", quiet=True, flags="f", type="raster", name=output)
+
+
+def generate_map(rows, cols, fname):
+    Module("g.region", flags="p", s=0, n=rows, w=0, e=cols, res=1)
+    # Generate using r.random.surface if r.surf.fractal fails
+    try:
+        print("Generating reference map using r.surf.fractal...")
+        Module("r.surf.fractal", output=fname)
+    except CalledModuleError:
+        print("r.surf.fractal fails, using r.random.surface instead...")
+        Module("r.random.surface", output=fname)
+
+
+if __name__ == "__main__":
+    main()