從幾何擴展點.STEnvelope（）

Question

我有一個簡單的幾何多邊形形狀。我可以使用STEnvelope（）獲取邊界框。我想按比例擴大點數，基本上縮小與截圖類似。

mssql服務器是否有能力做到這一點？

  DECLARE @g GEOMETRY; 
     SET @g = GEOMETRY::STPolyFromText('POLYGON((-122.358 47.653, -122.348 47.649, -122.348 47.658, -122.358 47.658, -122.358 47.653))', 4326); 
     SELECT @g.STEnvelope() 

更新： 我創建了一個演示SQL命令來縮放多邊形。而不是將它放置在右上方的新多邊形居中。

  DECLARE @zoom DECIMAL(22,22); 
     SET @zoom = 0.00001; 

     DECLARE @g GEOMETRY; 
     SET @g = geometry::STGeomFromText('POLYGON ((-12934935.9561 5405312.0569999963, -12934925.8363 5405305.5031, -12934930.8382 5405297.7252999991, -12934940.957899999 5405304.2792000026, -12934935.9561 5405312.0569999963))', 3857) 

     SELECT @g.STPointN(1) 
     UNION ALL 
     SELECT @g.STPointN(2) 
     UNION ALL 
     SELECT @g.STPointN(3) 
     UNION ALL 
     SELECT @g.STPointN(4) 
     UNION ALL 
     SELECT Geometry::Point(@g.STPointN(1).STX + (@g.STPointN(1).STX * (CASE WHEN @g.STPointN(1).STX > 0 THEN @zoom ELSE -@zoom END)), @g.STPointN(1).STY + (@g.STPointN(1).STY * (CASE WHEN @g.STPointN(1).STY > 0 THEN @zoom ELSE -@zoom END)), 3857) 
     UNION ALL 
     SELECT Geometry::Point(@g.STPointN(2).STX + (@g.STPointN(2).STX * (CASE WHEN @g.STPointN(2).STX > 0 THEN @zoom ELSE -@zoom END)), @g.STPointN(2).STY + (@g.STPointN(2).STY * (CASE WHEN @g.STPointN(2).STY > 0 THEN @zoom ELSE -@zoom END)), 3857) 
     UNION ALL 
     SELECT Geometry::Point(@g.STPointN(3).STX + (@g.STPointN(3).STX * (CASE WHEN @g.STPointN(3).STX > 0 THEN @zoom ELSE -@zoom END)), @g.STPointN(3).STY + (@g.STPointN(3).STY * (CASE WHEN @g.STPointN(3).STY > 0 THEN @zoom ELSE -@zoom END)), 3857) 
     UNION ALL 
     SELECT Geometry::Point(@g.STPointN(4).STX + (@g.STPointN(4).STX * (CASE WHEN @g.STPointN(4).STX > 0 THEN @zoom ELSE -@zoom END)), @g.STPointN(4).STY + (@g.STPointN(4).STY * (CASE WHEN @g.STPointN(4).STY > 0 THEN @zoom ELSE -@zoom END)), 3857) 

我在做什麼錯？

Answer 1

我已經放棄了ms sql版本，並使用Clipper http://www.angusj.com/delphi/clipper.php與c＃版本。