Descrizione

Scales the geometry to a new size by multiplying the ordinates with the corresponding factor parameters.

The version taking a geometry as the factor parameter allows passing a 2d, 3dm, 3dz or 4d point to set scaling factor for all supported dimensions. Missing dimensions in the factor point are equivalent to no scaling the corresponding dimension.

The three-geometry variant allows a "false origin" for the scaling to be passed in. This allows "scaling in place", for example using the centroid of the geometry as the false origin. Without a false origin, scaling takes place relative to the actual origin, so all coordinates are just multiplied by the scale factor.

	Prior to 1.3.4, this function crashes if used with geometries that contain CURVES. This is fixed in 1.3.4+

Availability: 1.1.0.

Migliorato: Nella 2.0.0 è stato introdotto il supporto per le superfici poliedriche, i triangoli e i TIN.

Enhanced: 2.2.0 support for scaling all dimension (factor parameter) was introduced.

Enhanced: 2.5.0 support for scaling relative to a local origin (origin parameter) was introduced.

Questa funzione supporta le Polyhedral Surface.

Questa funzione supporta il 3d e non distrugge gli z-index.

Questo metodo supporta le Curve e le Circular String.

Questa funzione supporta i Triangoli e le Triangulated Irregular Network Surfaces (TIN).

Questa funzione supporta le coordinate M.

Esempi

This example scales X, Y, and Z values.

SELECT ST_Scale('LINESTRING(1 2 3,1 1 1)', 0.5, 0.75, 0.8);

LINESTRING(0.5 1.5 2.4,0.5 0.75 0.8)

010200008002000000000000000000E03F000000000000F83F3433333333330340000000000000E03F000000000000E83F9A9999999999E93F

Figure

This example scales X and Y values.

SELECT ST_Scale('LINESTRING(1 2 3,1 1 1)', 0.5, 0.75);

LINESTRING(0.5 1.5 3,0.5 0.75 1)

010200008002000000000000000000E03F000000000000F83F0000000000000840000000000000E03F000000000000E83F000000000000F03F

Figure

This example scales X, Y, Z, and M values.

SELECT ST_Scale('LINESTRING(1 2 3 4,1 1 1 1)',
    ST_MakePoint(0.5, 0.75, 2, -1));

LINESTRING(0.5 1.5 6 -4,0.5 0.75 2 -1)

01020000C002000000000000000000E03F000000000000F83F000000000000184000000000000010C0000000000000E03F000000000000E83F0000000000000040000000000000F0BF

Figure

This example scales X and Y values using a false origin.

SELECT ST_Scale('LINESTRING(1 1,2 2)', 'POINT(2 2)', 'POINT(1 1)'::geometry);

LINESTRING(1 1,3 3)

010200000002000000000000000000F03F000000000000F03F00000000000008400000000000000840

Figure

Si veda anche

ST_Affine, ST_TransScale