[raster] ST_BandSurface returning a multipolygon of a band

[dustymugs]

Since an underlying C function is being written for use by various raster/raster spatial relationship functions, the C function might as well be exposed.

This could be done calling

ST_Union((ST_DumpAsPolygons()).geom)

or

ST_Union((ST_PixelAsPolygons()).geom)

but it may be that the underlying C function might be faster. No way to tell until the function is written.

ST_Surface(raster rast, integer nband DEFAULT 1) -> geometry

Suggestions on the function name? ST_Surface? ST_BandSurface? ST_???

[pracine]

ST_AsPolygon()? or ST_DumpAsPolygon(without s)?

[dustymugs]

Final function is named ST_BandSurface(). Added to trunk in r10055