Create a GeoTiff from an RDD of [(K, Iterator[(x, y, z)])]

create-geotiff-points.scala

import geotrellis.proj4._
import geotrellis.vector._
import geotrellis.raster._
import geotrellis.raster.io.geotiff._

import org.apache.spark.rdd._

trait Example {
  // Some information you'll need to supply...
  val crs = CRS.fromName("EPSG")

  // Depends on your key type
  type KeyType

  // The dimensions of each GeoTiff. You could derive this from each of
  // the groupings if need be.
  val (cols, rows): (Int, Int) = ???

  // We need to get the bounding box for the GeoTiff. I'm assuming this changes
  // per key, but perhaps it's only one extent for each key? If so this can be a
  // val instead of a def.
  def extentFromKey(k: KeyType): Extent = ???

  def filePathFromKey(k: KeyType): String = ???

  val rdd: RDD[(KeyType, Iterator[(Int, Int, Double)])] = ???

  rdd
    .foreach { case (key, iterator) =>
      val tile = DoubleArrayTile.empty(cols, rows)
      for((col, row, value) <- iterator) {
        tile.setDouble(col, row, value)
      }
      val extent = extentFromKey(key)
      val filePath = filePathFromKey(key)

      SingleBandGeoTiff(tile, extent, crs).write(filePath)
    }
}