Ciao a tutti,
ho fatto alcune prove con rasterlite.
Ho provato a combinare assieme due vestizioni della stessa mappa, in
formato geotiff, nella stesa piramide, in modo da visualizzare mappe con
diversi dettagli a scale diverse. Per farlo ho creato un file sql con un
serie di istruzioni, sfruttando le mie poche conoscenze del linguaggio
sql. Funziona a meraviglia.
Riporto il codice sql:
BEGIN ;
CREATE VIEW IF NOT EXISTS base250_rm AS
SELECT base250_rasters.id, raster, source_name, tile_id, width, height, pixel_x_size, pixel_y_size, geometry
FROM base250_rasters
JOIN base250_metadata ON (base250_rasters.id = base250_metadata.id) AND (base250_metadata.pixel_x_size < 160) ;
CREATE VIEW IF NOT EXISTS base500_rm AS
SELECT base500_rasters.id, raster, source_name, tile_id, width, height, pixel_x_size, pixel_y_size, geometry
FROM base500_rasters
JOIN base500_metadata ON (base500_metadata.id = base500_rasters.id) AND (base500_metadata.pixel_x_size >= 160) ;
COMMIT ;
ATTACH DATABASE "/home/marco/quantumnik/base10m/base.sqlite" AS "base" ;
BEGIN ;
CREATE TABLE base.base_metadata (
id INTEGER NOT NULL PRIMARY KEY,
source_name TEXT NOT NULL,
tile_id INTEGER NOT NULL,
width INTEGER NOT NULL,
height INTEGER NOT NULL,
pixel_x_size DOUBLE NOT NULL,
pixel_y_size DOUBLE NOT NULL, "geometry" POLYGON) ;
INSERT INTO base.base_metadata
SELECT * FROM base250_metadata
WHERE ROWID = 0 ;
CREATE TABLE base.base_rasters (
id INTEGER NOT NULL PRIMARY KEY AUTOINCREMENT,
raster BLOB NOT NULL) ;
COMMIT ;
BEGIN ;
INSERT INTO base.base_metadata
( "source_name", "tile_id", "width", "height", "pixel_x_size", "pixel_y_size", "geometry")
SELECT "source_name", "tile_id", "width", "height", "pixel_x_size", "pixel_y_size", "geometry"
FROM base250_rm
ORDER BY ROWID ;
INSERT INTO base.base_rasters (raster) SELECT raster FROM base250_rm ;
COMMIT ;
BEGIN ;
INSERT INTO base.base_metadata
( "source_name", "tile_id", "width", "height", "pixel_x_size", "pixel_y_size", "geometry")
SELECT "source_name", "tile_id", "width", "height", "pixel_x_size", "pixel_y_size", "geometry"
FROM base500_rm
ORDER BY ROWID ;
INSERT INTO base.base_rasters (raster) SELECT raster FROM base500_rm ;
COMMIT ;
BEGIN ;
INSERT INTO base.geometry_columns
("f_table_name", "f_geometry_column", "type", "coord_dimension", "srid", "spatial_index_enabled")
SELECT "f_table_name" AS base_metadata, "f_geometry_column", "type", "coord_dimension", "srid", "spatial_index_enabled"
FROM geometry_columns
WHERE ROWID = 1
ORDER BY ROWID ;
CREATE TABLE base.idx_base_metadata_geometry AS
SELECT * FROM idx_base250_metadata_geometry
ORDER BY ROWID ;
CREATE TABLE base.idx_base_metadata_geometry_node AS
SELECT * FROM idx_base250_metadata_geometry_node
ORDER BY ROWID ;
CREATE TABLE base.idx_base_metadata_geometry_parent AS
SELECT * FROM idx_base250_metadata_geometry_parent
ORDER BY ROWID ;
CREATE TABLE base.idx_base_metadata_geometry_rowid AS
SELECT * FROM idx_base250_metadata_geometry_rowid
ORDER BY ROWID ;
COMMIT ;