Function cannyGradientParallel

Bounded parallel variant of cannyGradient. Workers write disjoint rows.

raster.parallel_rows.ParallelRowsResult cannyGradientParallel(
  scope const(float)[] src,
  ulong w,
  ulong h,
  ref float[] gx,
  ref float[] gy,
  ref float[] magnitude,
  ulong workerLimit = 0LU,
  ulong minimumChunk = 1LU
) @trusted;