SDO_UTIL.BEARING_TILT_FOR

Format

SDO_UTIL.BEARING_TILT_FOR_POINTS(
     start_point IN SDO_GEOMETRY, 
     end_point   IN SDO_GEOMETRY, 
     tol         IN NUMBER, 
     bearing     OUT NUMBER, 
     tilt        OUT NUMBER 
     ) RETURN SDO_GEOMETRY;

Description

Computes the bearing and tilt from a start point to an end point.

Parameters

start_point: Starting point geometry object from which to compute the bearing and tilt. The point geometry must be based on a geodetic coordinate system.
end_point: Ending point geometry object to use in computing the bearing and tilt. The point geometry must be based on the same geodetic coordinate system as start_point.
tol: Tolerance value (see Tolerance).
bearing: Number of radians, measured clockwise from North.
tilt: Number of radians, measured from the normal.

Usage Notes

The input point geometries must be based on the same geodetic coordinate system. If they are based on a non-geodetic coordinate system, the output bearing is a null value.

The tilt is computed as the arctangent of the difference between the height values divided by the distance between the points (with height excluded from the distance calculation). That is: tilt = atan(height_difference/distance)

To convert radians to decimal degrees or decimal degrees to radians, you can use the SDO_UTIL.CONVERT_UNIT function. To return a point geometry that is at a specified distance and bearing from a start point, you can use the SDO_UTIL.POINT_AT_BEARING function.

Examples

The following example computes the bearing and tilt for two longitude/latitude points, where the elevation of the start point is 0 (zero) and the elevation of the end point is 5000 meters. This example displays the bearing and tilt values in radians.

DECLARE
  bearing NUMBER;
  tilt    NUMBER;
BEGIN
  SDO_UTIL.BEARING_TILT_FOR_POINTS(
    SDO_GEOMETRY(2001, 8307,
      SDO_POINT_TYPE(-71.5, 43, 0), NULL, NULL), -- start_point
    SDO_GEOMETRY(2001, 8307,
      SDO_POINT_TYPE(-71, 43.5, 5000), NULL, NULL), -- end_point
    0.05,  --tolerance
    bearing,
    tilt);
  DBMS_OUTPUT.PUT_LINE('Bearing = ' || bearing);
  DBMS_OUTPUT.PUT_LINE('Tilt = ' || tilt);
END;
/
Bearing = .628239101930666          
Tilt = .0725397288678286910476298724869396973718

The following example is the same as the preceding one, except that it displays the bearing and tilt in decimal degrees instead of radians.

DECLARE
  bearing NUMBER;
  tilt    NUMBER;
BEGIN
  SDO_UTIL.BEARING_TILT_FOR_POINTS(
    SDO_GEOMETRY(2001, 8307,
      SDO_POINT_TYPE(-71.5, 43, 0), NULL, NULL), -- start_point
    SDO_GEOMETRY(2001, 8307,
      SDO_POINT_TYPE(-71, 43.5, 5000), NULL, NULL), -- end_point
    0.05,  --tolerance
    bearing,
    tilt);
  DBMS_OUTPUT.PUT_LINE('Bearing in degrees = '  
    || bearing * 180 / 3.1415926535897932384626433832795);
  DBMS_OUTPUT.PUT_LINE('Tilt in degrees = ' 
    || tilt * 180 / 3.1415926535897932384626433832795);
END;
/
Bearing in degrees = 35.99544906571628894295547577999851892359
Tilt in degrees = 4.15622031114988533540349823511872120415