PostGIS的raster的api可以支持将栅格导出为图片,如ST_AsJPEG、ST_AsPNG,也有一些灰度图的API,如ST_Grayscale,可把栅格转灰度图图片作为webgl纹理渲染, ST_Grayscale 当然也可以后端直接上色气象栅格tif,通过geoserver等软件发布地理服务简单叠加: 尤其令人兴奋的时,在即将发布的PostGIS3.2版本,竟然有直接支持生成等值...
1.将multipolygon重构为polygon,并转为geojson格式 SELECT gid,st_asgeojson((ST_DUMP(geom)).geom::geometry(Polygon))AS geom FROM res_deference 查询结果如下图所示: 查询结果.png 但是,如果给SQLQuery传入类似 select name::varchar as n from table 包含双冒号的SQL, hibernate会认为是参数, 其中::应该...
dianzhou=# select start_vid,end_vid,st_astext(ST_Union(geom)) from a group by start_vid,end_vid;start_vid|end_vid|st_astext---+---+---
用性的函数,可以导出为GDAL支持的随意格式。此外,还有ST_AsPNG,ST_AsJPEG和 ST_AsTIFF等函数,提供了挺直导出到指定格式,并且接受更少的参数。 注重:PostGIS的默认导出GDAL支持的格式数据是关闭的,启用的话需要修改PostgreSQL 的配置文件。修改的办法比较多,而且不同的PostgreSQL版本的支持状况不一样。我用法如 ...
合并后的图形.png 如果是“缝补”不了的图形,如下: SELECT ST_AsText(ST_LineMerge( ST_GeomFromText('MULTILINESTRING((-29-27,-30-29.7,-36-31,-45-33),(-45.2-33.2,-46-32)) ')) ); st_astext --- MULTILINESTRING((-45.2-33.2,-46-32),(-29-27,-30-29.7,-36-31,-45-33)) 缝补不...
cpp，则为g++ -g -o x x.cpp // 需要带一个命令行参数argv[1]， // 必 ...
st_astext(postgis.geometry) doesn't exist while trying to query st_astext(bbox) function [image: image.png] database search path is already set with 'postgis' but still sees the error. [image: image.png] Can you please advise what is the issue here?
[0], double precision upperleftx=NULL, double precision upperlefty=NULL, double precision skewx=0, double precision skewy=0, boolean touched=false); //示例 -- this will output a black circle taking up 150 x 150 pixels -- SELECT ST_AsPNG(ST_AsRaster(ST_Buffer(ST_Point(1,5),10),...
SELECT ST_X(geom), ST_Y(geom) FROM geometries WHERE name = 'Point';分别返回x\y坐标值 9.3.2linestring closed:首尾点相同的线 simple:线没有自身相交或者相邻接的情况(closed时,末尾点除外); 一个线可以是closed和simple; 返回线的文字表达:SELECT ST_AsText(geom) FROM geometries WHERE name = 'Li...
Raster Outputs ST_AsBinary, ST_AsGDALRaster, ST_AsJPEG, ST_AsPNG, and ST_AsTIFF Raster Processing ST_Clip, ST_ColorMap, ST_Intersection, ST_MapAlgebra, ST_Reclass, and ST_Union ST_Distinct4ma, ST_InvDistWeight4ma, ST_Max4ma, ST_Mean4ma, ST_Min4ma, ST_MinDist4ma, ST_Range4...