[Gfoss] grid poligonale su raster

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— Dom 28/2/10, Zucchini Antonio zucchiniantonio@yahoo.it ha scritto:


> IOvviamente parlo sempre di dato vettoriale per il postgis, per il qgis non ho capito come rendere trasparente il fill perchè se metto tutto trasparente sopra il raster sotto non appare in ogni caso,
>
> avevo già capito che dovevo rendere trasparente solo il fill e non il contorno ma non trovo in qgis l’opzione adatta.
>
> Per la tabella di parametri di grid la utilizzo per generare dinamicamente delle grid vettoriale partendo da parametri che possono essere anche definiti dall’utente finale (i ricercatori) che nula sanno e nulla vogliono sapere dei dettagli implementativi del modello logico e di archittetura del GIS.
>
> Riporto un esempio di script di generazione:
>
> INSERT
> INTO delphis.grids
> (parameter
> ,lon_index
> ,lat_index
> ,quota_index
> ,lon_south_west
> ,lat_south_west
> ,quota_south_west
> ,lon_south_east
> ,lat_south_east
> ,quota_south_east
> ,lon_north_east
> ,lat_north_east
> ,quota_north_east
> ,lon_north_west
> ,lat_north_west
> ,quota_north_west
> ,polygon_utm_wgs84
> )
> SELECT polygrid.parameter
> ,lon_index
> ,lat_index
> ,0 as quota_index
> ,lon_south_west + (lon_index-1) * cell_length as lon_sw
> ,lat_south_west + (lat_index-1) * cell_length as lat_sw
> ,quota_south_west + 0 as quota_sw
> ,lon_south_east + (lon_index-1) * cell_length as lon_se
> ,lat_south_east + (lat_index-1) * cell_length as lat_se
> ,quota_south_east + 0 as quota_se
> ,lon_north_east + (lon_index-1) * cell_length as lon_ne
> ,lat_north_east + (lat_index-1) * cell_length as lon_ne
> ,quota_north_east + 0 as quota_ne
> ,lon_north_west + (lon_index-1) * cell_length as lon_nw
> ,lat_north_west + (lat_index-1) * cell_length as lat_nw
> ,quota_north_west + 0 as quota_nw
> ,ST_TRANSLATE(cell,(lon_index-1) * cell_length , (lat_index-1) * cell_length, 0) as grid_element
> FROM
> (
> SELECT parameter
> ,GENERATE_SERIES(1,cells_side+1) as lon_index
> FROM delphis.parameters_grid
> WHERE COALESCE(status_grid,‘NOBUILT’) = ‘NOBUILT’
> ) lon_series,
> (
> SELECT parameter
> ,GENERATE_SERIES(1,cells_side+1) as lat_index
> FROM delphis.parameters_grid
> WHERE COALESCE(status_grid,‘NOBUILT’) = ‘NOBUILT’
> ) lat_series,
> (
> SELECT parameter
> ,cell_length
> ,cells_side
> ,low_corner_lon as lon_south_west
> ,low_corner_lat as lat_south_west
> ,low_corner_quota as quota_south_west
> ,low_corner_lon as lon_south_east
> ,low_corner_lat+cell_length as lat_south_east
> ,low_corner_quota as quota_south_east
> ,low_corner_lon+cell_length as lon_north_east
> ,low_corner_lat+cell_length as lat_north_east
> ,low_corner_quota as quota_north_east
> ,low_corner_lon+cell_length as lon_north_west
> ,low_corner_lat as lat_north_west
> ,low_corner_quota as quota_north_west
> ,srid
> ,ST_MAKEPOLYGON(
> ST_MAKELINE(
> ARRAY[ST_SETSRID(ST_MAKEPOINT(low_corner_lon ,low_corner_lat ,low_corner_quota),srid)::geometry
> ,ST_SETSRID(ST_MAKEPOINT(low_corner_lon ,low_corner_lat+cell_length,low_corner_quota),srid)::geometry
> ,ST_SETSRID(ST_MAKEPOINT(low_corner_lon+cell_length,low_corner_lat+cell_length,low_corner_quota),srid)::geometry
> ,ST_SETSRID(ST_MAKEPOINT(low_corner_lon+cell_length,low_corner_lat ,low_corner_quota),srid)::geometry
> ,ST_SETSRID(ST_MAKEPOINT(low_corner_lon ,low_corner_lat ,low_corner_quota),srid)::geometry
> ]
> )
> ) as cell
> FROM delphis.parameters_grid pg
> WHERE COALESCE(status_grid,‘NOBUILT’) = ‘NOBUILT’
> ORDER
> BY cell_length
> ,parameter
> ) polygrid
> WHERE lat_series.parameter = polygrid.parameter
> AND lon_series.parameter = polygrid.parameter
> ORDER
> BY cell_length
> ,polygrid.parameter
> ,lon_index
> ,lat_index;
> update delphis.grids set polygon_wgs84 = st_transform(polygon_utm_wgs84,4326);
> update delphis.grids set polygon_utm_ed50 = st_transform(polygon_utm_wgs84,23033);
> update delphis.parameters_grid
> set status_grid = ‘BUILT’
> where coalesce(status_grid,‘NOBUILT’) = ‘NOBUILT’;
> commit;