I reprojected a natural earth raster file (Natural Earth II with Shaded Relief, Water, and Drainages, CRS WGS84) with a costum CRS (azimuthal orthografic) using Raster->Projections->Warp in QGIS. Worked fine except glitches at the international date line and at the horizon of the hemisphere (see attached image). An idea how I can prevent these?
Edit: as @user30184 suggests adding
-wo SAMPLE_STEPS=100 and
-wo SOURCE_EXTRA=10 fixes the glitches