Add gdal raster mosaic

[dbaston]

Feature description

Rename the current gdal raster buildvrt to gdal raster mosaic and allow output in any supported format.

Additional context

As discussed in #11558 (comment)

[jratike80]

I am not totally sure if t a good idea to support any supported format. Mosaics can be big, some formats will not work at all, and for the drivers that work user should be aware of reasonable options. But yes, they need to know them when they materialize the vrt anyway.

"Mosaic" feels good when flat images are stiched side by side, but how about combining bands with -separate. Is the result so much a mosaic?

[dbaston]

"Mosaic" feels good when flat images are stiched side by side, but how about combining bands with -separate.

Maybe this could be a separate command, something like gdal raster stack ?

[jratike80]

Maybe this could be a separate command, something like gdal raster stack ?

Makes me think about https://stacspec.org/en that can be flat or deep, or cube. Pile?

[mdsumner]

I think we see the issue where gdalwarp is the superset that includes gdal_translate. I would just vote for

gdalwarp <inputs> output.<ext>

but, as ever that's weird for cases that don't involve reprojection or even resampling. How is a "mosaic" functionally different from this?

gdal raster reproject <inputs> output.<ext>

warp is currently standing in for merge,mosaic,reproject,translate and I think that needs some thought - can we sensibly refactor this? Maybe "convert" should do mosaicing-via-warper when needed, and normal "translate" otherwise.

(I will explore this more, just those immediate thoughts). I overall support "mosaic" as a concept in addition to "convert", "reproject" and I think that's clean enough despite the fair amount of functional overlap.