描述

以地理参考栅格的几何单位返回栅格列行的左上角X坐标。列数和行数从1开始，但如果传入的是负数或大于栅格中列数的数值，则会在假定倾斜和像素大小与所选栅格相同的情况下，将栅格文件外部的坐标向左或向右提供。

	对于非倾斜栅格，提供X列就足够了。对于倾斜的栅格，地理参考坐标是ST_ScaleX和ST_SkewX以及行和列的函数。如果只为倾斜的栅格提供X列，则会引发错误。

已更改：2.1.0在以前的版本中，这称为ST_Raster2WorldCoordX

示例

-- non-skewed raster providing column is sufficient
SELECT rid, ST_RasterToWorldCoordX(rast,1) As x1coord,
    ST_RasterToWorldCoordX(rast,2) As x2coord,
    ST_ScaleX(rast) As pixelx
FROM dummy_rast;

 rid |  x1coord   |  x2coord  | pixelx
-----+------------+-----------+--------
   1 |        0.5 |       2.5 |      2
   2 | 3427927.75 | 3427927.8 |   0.05
                

-- for fun lets skew it
SELECT rid, ST_RasterToWorldCoordX(rast, 1, 1) As x1coord,
    ST_RasterToWorldCoordX(rast, 2, 3) As x2coord,
    ST_ScaleX(rast) As pixelx
FROM (SELECT rid, ST_SetSkew(rast, 100.5, 0) As rast FROM dummy_rast) As foo;

 rid |  x1coord   |  x2coord  | pixelx
-----+------------+-----------+--------
   1 |        0.5 |     203.5 |      2
   2 | 3427927.75 | 3428128.8 |   0.05
                

另请参阅

ST_ScaleX, ST_RasterToWorldCoordY, ST_SetSkew, ST_SkewX