在上一篇博文基於postGIS的室內地圖最短路徑演算法三，雖然路徑分析的結果，最後返回了起點到終點的完整線路，但是可能產生起點或終點到路網的連線穿越障礙物的情況，這裡就需要用虛線表示。

       這樣就需要將路徑分析的結果分三條記錄返回，起點到路網、路網中路徑、路網到終點線，並需要對這三段線進行區別。然後在Goeserver中配置樣式。

執行結果如下圖所示：

資料庫程式碼：

--DROP FUNCTION pgr_floor_test3(character varying, double precision, double precision, double precision, double precision, integer);
--tbl路網表名
--startx起點經度
--starty起點緯度
--endx終點經度
--endy終點緯度
--fnumber樓層
CREATE OR REPLACE function pgr_floor_test3(IN tbl varchar,IN startx float,IN starty float,IN endx float,IN endy float,IN fnumber integer,OUT lineType integer,OUT geom geometry) 
 
--限制返回型別
returns SETOF  record as 

$body$  

  

declare 

    fmin integer;
    fmax integer;

    v_startLine geometry;--離起點最近的線 

    v_endLine geometry;--離終點最近的線 

     

    v_startTarget integer;--距離起點最近線的終點

    v_startSource integer;

    v_endSource integer;--距離終點最近線的起點

    v_endTarget integer;

 

    v_statpoint geometry;--在v_startLine上距離起點最近的點 

    v_endpoint geometry;--在v_endLine上距離終點最近的點 

     

    v_res geometry;--最短路徑分析結果

    v_res_a geometry;

    v_res_b geometry;

    v_res_c geometry;

    v_res_d geometry; 

 

    v_perStart float;--v_statpoint在v_res上的百分比 

    v_perEnd float;--v_endpoint在v_res上的百分比 

 

    v_shPath_se geometry;--開始到結束

    v_shPath_es geometry;--結束到開始

    v_shPath geometry;--最終結果

    tempnode float;  
    
    startpoint geometry;
    endpoint geometry;

    v_shPath1 geometry;--一次結果
    v_shPath2 geometry;--二次結果
    star_line geometry; --起點到最近點的線
    end_line geometry; --終點到最近點的線
    geoARR geometry[];
    
    geoType integer[];
    
    lines myline[];--返回線集
    line1 myline;
    line2 myline;
    line3 myline;
    
    ii integer;

begin

fmin=fnumber*1000;
fmax=fmin+1000;
raise notice '%', fmin;
raise notice '%', fmax;
    --查詢離起點最近的線 
    --4326座標系
    --找起點15米範圍內的最近線

    execute 'select geom, source, target  from ' ||tbl||

                            ' where ST_DWithin(geom,ST_Geometryfromtext(''point('||         startx ||' ' || starty||')'',4326),15)

                            and source between '||fmin||' and '||fmax||' order by ST_Distance(geom,ST_GeometryFromText(''point('|| startx ||' '|| starty ||')'',4326))  limit 1'

                            into v_startLine, v_startSource ,v_startTarget; 

raise notice '%',  v_startSource;
raise notice '%', v_startTarget;

    --查詢離終點最近的線 
    --找終點15米範圍內的最近線

    execute 'select geom, source, target from ' ||tbl||

                            ' where ST_DWithin(geom,ST_Geometryfromtext(''point('|| endx || ' ' || endy ||')'',4326),15) 
                            and source between '||fmin||' and '||fmax||' 

                            order by ST_Distance(geom,ST_GeometryFromText(''point('|| endx ||' ' || endy ||')'',4326))  limit 1'

                            into v_endLine, v_endSource,v_endTarget; 
raise notice '%',  v_endSource;
raise notice '%', v_endTarget;
 

    --如果沒找到最近的線，就返回null 

    if (v_startLine is null) or (v_endLine is null) then 

        return; 

    end if ; 

 

    select  ST_ClosestPoint(v_startLine, ST_Geometryfromtext('point('|| startx ||' ' || starty ||')',4326)) into v_statpoint; 

    select  ST_ClosestPoint(v_endLine, ST_GeometryFromText('point('|| endx ||' ' || endy ||')',4326)) into v_endpoint; 

   

   -- ST_Distance 

     

    --從開始的起點到結束的起點最短路徑

    execute 'SELECT st_linemerge(st_union(b.geom)) ' ||

    'FROM pgr_kdijkstraPath( 

    ''SELECT gid as id, source, target, length as cost FROM ' || tbl ||''',' 

    ||v_startSource || ', ' ||'array['||v_endSource||'] , false, false 

    ) a, ' 

    || tbl || ' b 

    WHERE a.id3=b.gid   

    GROUP by id1   

    ORDER by id1' into v_res ;

   

    --從開始的終點到結束的起點最短路徑

    execute 'SELECT st_linemerge(st_union(b.geom)) ' ||

    'FROM pgr_kdijkstraPath( 

    ''SELECT gid as id, source, target, length as cost FROM ' || tbl ||''',' 

    ||v_startTarget || ', ' ||'array['||v_endSource||'] , false, false 

    ) a, ' 

    || tbl || ' b 

    WHERE a.id3=b.gid   

    GROUP by id1   

    ORDER by id1' into v_res_b ;

 

    --從開始的起點到結束的終點最短路徑

    execute 'SELECT st_linemerge(st_union(b.geom)) ' ||

    'FROM pgr_kdijkstraPath( 

    ''SELECT gid as id, source, target, length as cost FROM ' || tbl ||''',' 

    ||v_startSource || ', ' ||'array['||v_endTarget||'] , false, false 

    ) a, ' 

    || tbl || ' b 

    WHERE a.id3=b.gid   

    GROUP by id1   

    ORDER by id1' into v_res_c ;

 

    --從開始的終點到結束的終點最短路徑

    execute 'SELECT st_linemerge(st_union(b.geom)) ' ||

    'FROM pgr_kdijkstraPath( 

    ''SELECT gid as id, source, target, length as cost FROM ' || tbl ||''',' 

    ||v_startTarget || ', ' ||'array['||v_endTarget||'] , false, false 

    ) a, ' 

    || tbl || ' b 

    WHERE a.id3=b.gid   

    GROUP by id1   

    ORDER by id1' into v_res_d ;

 

    if(ST_Length(v_res) > ST_Length(v_res_b)) then

       v_res = v_res_b;

    end if;

   

    if(ST_Length(v_res) > ST_Length(v_res_c)) then

       v_res = v_res_c;

    end if;

   

    if(ST_Length(v_res) > ST_Length(v_res_d)) then

       v_res = v_res_d;

    end if;

             

 

    --如果找不到最短路徑，就返回null 

    if(v_res is null) then 

        return; 

    end if; 

     

    --將v_res,v_startLine,v_endLine進行拼接 

    select  st_linemerge(ST_Union(array[v_res,v_startLine,v_endLine])) into v_res;

    --return v_res;

    select  ST_LineLocatePoint(v_res, v_statpoint) into v_perStart; 

    select  ST_LineLocatePoint(v_res, v_endpoint) into v_perEnd; 

        

    if(v_perStart > v_perEnd) then 

        tempnode =  v_perStart;

        v_perStart = v_perEnd;

        v_perEnd = tempnode;

    end if;

        

    --擷取v_res 
    --拼接線

    SELECT ST_Line_SubString(v_res,v_perStart, v_perEnd) into v_shPath1;

 --接下來進行
 --找線的端點
 -- select  ST_ClosestPoint(v_endLine, ST_GeometryFromText('point('|| endx ||' ' || endy ||')',4326)) into v_endpoint; 
-- select ST_MakePoint(endx , endy) into startpoint;
   select ST_SetSRID( ST_MakePoint(startx , starty),4326 )into startpoint;
 select ST_SetSRID( ST_MakePoint(endx , endy),4326 )into endpoint;
 select ST_MakeLine( v_statpoint,startpoint) into star_line; 
 select ST_MakeLine( v_endpoint,endpoint) into end_line; 
 
-- select st_union(end_line,v_shPath1) into v_shPath2;
--select st_union(star_line,v_shPath2) into v_shPath;

--line1.id=1;
--line1.geom=star_line;
--line2.id=2;
--line2.geom=v_shPath1;
--line3.id=3;
--line3.geom=end_line;

--lines[0]=line1;
--lines[1]=line2;
--lines[2]=line3;
geoARR :=array[end_line,v_shPath1,star_line];
geoType :=array[1,2,1];
--select st_union(geoARR) into v_shPath;
 
 --raise notice '%', '返回資料';
 --OUT lineType integer,OUT geom geometry
    FOR ii IN 1..3 Loop 
 
    lineType:=geoType[ii];
    geom:=geoARR[ii];
    raise notice '%', '返回資料';
    return next;
    end loop;
 return;
 

    --return geoARR; 
    --return lines;
    --return v_shPath;

 

end; 

$body$ 

LANGUAGE plpgsql VOLATILE STRICT;
 

樣式程式碼如下：

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    <sld:UserLayer>
        <sld:LayerFeatureConstraints>
            <sld:FeatureTypeConstraint/>
        </sld:LayerFeatureConstraints>
       <sld:UserStyle>
            <sld:Name>F34</sld:Name>
            <sld:FeatureTypeStyle>
                <sld:Name>group 0</sld:Name>
                <sld:FeatureTypeName>Feature</sld:FeatureTypeName>
                <sld:SemanticTypeIdentifier>generic:geometry</sld:SemanticTypeIdentifier>
                <sld:SemanticTypeIdentifier>simple</sld:SemanticTypeIdentifier>
                <sld:Rule>
                    <sld:Name>虛線</sld:Name>
                    <ogc:Filter>
                        <ogc:PropertyIsEqualTo>
                            <ogc:PropertyName>linetype</ogc:PropertyName>
                            <ogc:Literal>1</ogc:Literal>
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                    <sld:LineSymbolizer>
                        <sld:Stroke>
                            <sld:CssParameter name="stroke">#00FF40</sld:CssParameter>
                            <sld:CssParameter name="stroke-width">2.0</sld:CssParameter>
                            <sld:CssParameter name="stroke-dasharray">5.0</sld:CssParameter>
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                </sld:Rule>
                <sld:Rule>
                    <sld:Name>實線</sld:Name>
                    <ogc:Filter>
                        <ogc:PropertyIsEqualTo>
                            <ogc:PropertyName>linetype</ogc:PropertyName>
                            <ogc:Literal>2</ogc:Literal>
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                    </ogc:Filter>
                    <sld:LineSymbolizer>
                        <sld:Stroke>
                            <sld:CssParameter name="stroke">#FF0000</sld:CssParameter>
                            <sld:CssParameter name="stroke-width">2.0</sld:CssParameter>
                        </sld:Stroke>
                    </sld:LineSymbolizer>
                </sld:Rule>
            </sld:FeatureTypeStyle>
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