Clip artifacts at low zoom

[kylebarron]

You could try math.ceil and math.floor instead of round here:

usgs-topo-tiler/usgs_topo_tiler/usgs_topo.py

Lines 49 to 52 in b41a4f0

	left = round(buffers[0] / crs_width * img_width)
	bottom = img_height - round(buffers[1] / crs_height * img_height)
	right = img_width - round(buffers[2] / crs_width * img_width)
	top = round(buffers[3] / crs_height * img_height)

That would slightly overcompensate, but then the gaps would be white, instead of whatever the background color is.

[kylebarron]

Helped with 8cc581d, which removed the rounding. But there's still some artifacts. I'm not sure I want to round up, since that could add white borders where the tile junction is even. For now this is fine.