Assume correct extents in binary operationsto avoid floating point er…

…rors (#91)

jvm/src/main/scala/eval/tile/LazyRaster.scala

@@ -95,7 +95,7 @@ object LazyRaster {
     require(children.length == arity, s"Incorrect arity: $arity argument(s) expected, ${children.length} found")
     def fst = children(0)
     def snd = children(1)
-    def rasterExtent: RasterExtent = fst.rasterExtent combine snd.rasterExtent
+    def rasterExtent: RasterExtent = fst.rasterExtent
     def crs = fst.crs
   }