I wasn't suggesting that it be a method on RasterData, it was the toRasterData method....

```scala
def toRasterData(aw: ArgWritable, awType: RasterType, cols: Int, rows: Int)
```

So instead of 
```scala
val aw:ArgWritable = ???
ArgWritabe.toRasterData(aw, rasterType, cols, rows)
```
it could be

```scala
val aw:ArgWritable = ???
aw.toRasterData(rasterType, cols, rows)
```