Row of No Data Pixels returned from Raster Source Read

[notthatbreezy]

Describe the bug

When performing a tile read from a RasterSource for a tiff that is supposed to be 256x256 sometimes the resulting tile includes a single row of no data at the bottom of the tile.

To Reproduce

I've attached a zip file that has the steps to reproduce this bug, including a tiff that exhibits the behavior. To run this - install ammonite, unzip the file, and run amm test-script-worksheet.sc

This only seems to be happening for zoom level 19 - when running the script here is some sample output:

Debug info for: (307710, 257618)
Tile sum:  65280
Tile size: 65536
Debug info for: (307711, 257615)
Tile sum:  65280
Tile size: 65536
Debug info for: (307711, 257616)
Tile sum:  65280
Tile size: 65536
Debug info for: (307711, 257617)
Tile sum:  65280
Tile size: 65536
Debug info for: (307711, 257618)
Tile sum:  65280
Tile size: 65536

The value for the sum and size should be the same: 65536 but they are not - there are 256 nodata values present in the the tile read, though the dimensions are correct 256 x 256.

Expected behavior

Data should be returned for all pixels for this test case.

Screenshots

In practice this manifests as blank lines of pixels when rendering PNGs

Environment

• Java version: 8
• Scala version: 2.12
• GeoTrellis version: tested on 3.4 and 3.5

nodata-tiles.zip