pggeodb.nancy.inra.fr/db_toff - db_toff on pggeodb.nancy.inra.fr

Function: st_iscoveragetile

Schema

public

Owner

postgres

Descriptions

There is no description for function st_iscoveragetile

Options

Definition

CREATE OR REPLACE FUNCTION public.st_iscoveragetile (
 rast public.raster,
 coverage public.raster,
 tilewidth integer,
 tileheight integer
)
RETURNS boolean AS
$span$
DECLARE
_rastmeta record;
_covmeta record;
cr record;
max integer[];
tile integer[];
edge integer[];
BEGIN
IF NOT ST_SameAlignment(rast, coverage) THEN
RAISE NOTICE 'Raster and coverage are not aligned';
RETURN FALSE;
END IF;

_rastmeta := ST_Metadata(rast);
_covmeta := ST_Metadata(coverage);

-- get coverage grid coordinates of upper-left of rast
cr := ST_WorldToRasterCoord(coverage, _rastmeta.upperleftx, _rastmeta.upperlefty);

-- rast is not part of coverage
IF
(cr.columnx < 1 OR cr.columnx > _covmeta.width) OR
(cr.rowy < 1 OR cr.rowy > _covmeta.height)
THEN
RAISE NOTICE 'Raster is not in the coverage';
RETURN FALSE;
END IF;

-- rast isn't on the coverage's grid
IF
((cr.columnx - 1) % tilewidth != 0) OR
((cr.rowy - 1) % tileheight != 0)
THEN
RAISE NOTICE 'Raster is not aligned to tile grid of coverage';
RETURN FALSE;
END IF;

-- max # of tiles on X and Y for coverage
max[0] := ceil(_covmeta.width::double precision / tilewidth::double precision)::integer;
max[1] := ceil(_covmeta.height::double precision / tileheight::double precision)::integer;

-- tile # of rast in coverge
tile[0] := (cr.columnx / tilewidth) + 1;
tile[1] := (cr.rowy / tileheight) + 1;

-- inner tile
IF tile[0] < max[0] AND tile[1] < max[1] THEN
IF
(_rastmeta.width != tilewidth) OR
(_rastmeta.height != tileheight)
THEN
RAISE NOTICE 'Raster width/height is invalid for interior tile of coverage';
RETURN FALSE;
ELSE
RETURN TRUE;
END IF;
END IF;

-- edge tile

-- edge tile may have same size as inner tile
IF
(_rastmeta.width = tilewidth) AND
(_rastmeta.height = tileheight)
THEN
RETURN TRUE;
END IF;

-- get edge tile width and height
edge[0] := _covmeta.width - ((max[0] - 1) * tilewidth);
edge[1] := _covmeta.height - ((max[1] - 1) * tileheight);

-- edge tile not of expected tile size
-- right and bottom
IF tile[0] = max[0] AND tile[1] = max[1] THEN
IF
_rastmeta.width != edge[0] OR
_rastmeta.height != edge[1]
THEN
RAISE NOTICE 'Raster width/height is invalid for right-most AND bottom-most tile of coverage';
RETURN FALSE;
END IF;
ELSEIF tile[0] = max[0] THEN
IF
_rastmeta.width != edge[0] OR
_rastmeta.height != tileheight
THEN
RAISE NOTICE 'Raster width/height is invalid for right-most tile of coverage';
RETURN FALSE;
END IF;
ELSE
IF
_rastmeta.width != tilewidth OR
_rastmeta.height != edge[1]
THEN
RAISE NOTICE 'Raster width/height is invalid for bottom-most tile of coverage';
RETURN FALSE;
END IF;
END IF;

RETURN TRUE;
END;
$span$
LANGUAGE 'plpgsql'
IMMUTABLE
RETURNS NULL ON NULL INPUT
SECURITY INVOKER
COST 100;

This file was generated with SQL Manager for PostgreSQL (www.pgsqlmanager.com) at 13/03/2014 13:23