SIST EN ISO 19125-1:2006
(Main)Geographic information - Simple feature access - Part 1: Common architecture (ISO 19125-1:2004)
Geographic information - Simple feature access - Part 1: Common architecture (ISO 19125-1:2004)
This part of ISO 19125 establishes a common architecture and defines terms to use within the architecture. This part of ISO 19125 does not attempt to standardize and does not depend upon any part of the mechanism by which Types are added and maintained, including the following: a) syntax and functionality provided for defining types; b) syntax and functionality provided for defining functions; c) physical storage of type instances in the database; d) specific terminology used to refer to User Defined Types, for example UDT. This part of ISO 19125 does standardize names and geometric definitions for Types for Geometry. This part of ISO 19125 does not place any requirements on how to define the Geometry Types in the internal schema nor does it place any requirements on when or how or who defines the Geometry Types.
Geoinformation - Simple feature access - Teil 1 : Gemeinsame Architektur (ISO 19125-1:2004)
Information géographique - Acces aux entités simples - Partie 1: Architecture commune (ISO 19125-1:2004)
Geografske informacije - Dostop do enostavnih pojavov - 1. del: Skupna arhitektura (ISO 19125-1:2004)
General Information
Standards Content (Sample)
SLOVENSKI STANDARD
SIST EN ISO 19125-1:2006
01-junij-2006
Geografske informacije - Dostop do enostavnih pojavov - 1. del: Skupna
arhitektura (ISO 19125-1:2004)
Geographic information - Simple feature access - Part 1: Common architecture (ISO
19125-1:2004)
Geoinformation - Simple feature access - Teil 1 : Gemeinsame Architektur (ISO 19125-
1:2004)
Information géographique - Acces aux entités simples - Partie 1: Architecture commune
(ISO 19125-1:2004)
Ta slovenski standard je istoveten z: EN ISO 19125-1:2006
ICS:
07.040 Astronomija. Geodezija. Astronomy. Geodesy.
Geografija Geography
35.240.70 Uporabniške rešitve IT v IT applications in science
znanosti
SIST EN ISO 19125-1:2006 en
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
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SIST EN ISO 19125-1:2006
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SIST EN ISO 19125-1:2006
EUROPEAN STANDARD
EN ISO 19125-1
NORME EUROPÉENNE
EUROPÄISCHE NORM
March 2006
ICS 35.240.70
English Version
Geographic information - Simple feature access - Part 1:
Common architecture (ISO 19125-1:2004)
Information géographique - Accès aux entités simples - Geoinformation - Simple feature access - Teil 1 :
Partie 1: Architecture commune (ISO 19125-1:2004) Gemeinsame Architektur (ISO 19125-1:2004)
This European Standard was approved by CEN on 16 February 2006.
CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this European
Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical references concerning such national
standards may be obtained on application to the Central Secretariat or to any CEN member.
This European Standard exists in three official versions (English, French, German). A version in any other language made by translation
under the responsibility of a CEN member into its own language and notified to the Central Secretariat has the same status as the official
versions.
CEN members are the national standards bodies of Austria, Belgium, Cyprus, Czech Republic, Denmark, Estonia, Finland, France,
Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania,
Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION
EUROPÄISCHES KOMITEE FÜR NORMUNG
Management Centre: rue de Stassart, 36 B-1050 Brussels
© 2006 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 19125-1:2006: E
worldwide for CEN national Members.
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SIST EN ISO 19125-1:2006
EN ISO 19125-1:2006 (E)
Foreword
The text of ISO 19125-1:2004 has been prepared by Technical Committee ISO/TC 211
"Geographic information/Geomatics” of the International Organization for Standardization (ISO)
and has been taken over as EN ISO 19125-1:2006 by Technical Committee CEN/TC 287
"Geographic Information", the secretariat of which is held by NEN.
This European Standard shall be given the status of a national standard, either by publication of
an identical text or by endorsement, at the latest by September 2006, and conflicting national
standards shall be withdrawn at the latest by September 2006.
According to the CEN/CENELEC Internal Regulations, the national standards organizations of
the following countries are bound to implement this European Standard: Austria, Belgium,
Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary,
Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland,
Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom.
Endorsement notice
The text of ISO 19125-1:2004 has been approved by CEN as EN ISO 19125-1:2006 without any
modifications.
2
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SIST EN ISO 19125-1:2006
INTERNATIONAL ISO
STANDARD 19125-1
First edition
2004-08-01
Geographic information — Simple feature
access —
Part 1:
Common architecture
Information géographique — Accès aux entités simples —
Partie 1: Architecture commune
Reference number
ISO 19125-1:2004(E)
©
ISO 2004
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SIST EN ISO 19125-1:2006
ISO 19125-1:2004(E)
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ii © ISO 2004 – All rights reserved
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SIST EN ISO 19125-1:2006
ISO 19125-1:2004(E)
Contents Page
Foreword. iv
Introduction . v
1 Scope. 1
2 Conformance . 1
3 Normative references . 1
4 Terms and definitions. 1
5 Abbreviated terms. 4
6 Architecture . 5
6.1 Geometry object model . 5
6.2 Well-known Text Representation for Geometry. 21
6.3 Well-known Binary Representation for Geometry. 22
6.4 Well-known Text Representation of Spatial Reference Systems. 25
Annex A (informative) The correspondence of concepts of the common architecture with
concepts of the geometry model of ISO 19107. 28
Annex B (informative) Supported spatial reference data . 36
Bibliography . 42
© ISO 2004 – All rights reserved iii
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SIST EN ISO 19125-1:2006
ISO 19125-1:2004(E)
Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards bodies
(ISO member bodies). The work of preparing International Standards is normally carried out through ISO
technical committees. Each member body interested in a subject for which a technical committee has been
established has the right to be represented on that committee. International organizations, governmental and
non-governmental, in liaison with ISO, also take part in the work. ISO collaborates closely with the
International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization.
International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 2.
The main task of technical committees is to prepare International Standards. Draft International Standards
adopted by the technical committees are circulated to the member bodies for voting. Publication as an
International Standard requires approval by at least 75 % of the member bodies casting a vote.
Attention is drawn to the possibility that some of the elements of this document may be the subject of patent
rights. ISO shall not be held responsible for identifying any or all such patent rights.
ISO 19125-1 was prepared by Technical Committee ISO/TC 211, Geographic information/Geomatics from a
base document supplied by the Open GIS Consortium, Inc.
ISO 19125 consists of the following parts, under the general title Geographic information — Simple feature
access:
— Part 1: Common architecture
— Part 2: SQL option
A Part 3: COM/OLE option is under preparation.
iv © ISO 2004 – All rights reserved
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SIST EN ISO 19125-1:2006
ISO 19125-1:2004(E)
Introduction
This part of ISO 19125 describes the common architecture for simple feature geometry. The simple feature
geometry object model is Distributed Computing Platform neutral and uses UML notation. The base Geometry
class has subclasses for Point, Curve, Surface and GeometryCollection. Each geometric object is associated
with a Spatial Reference System, which describes the coordinate space in which the geometric object is
defined.
The extended Geometry model has specialized 0, 1 and 2-dimensional collection classes named MultiPoint,
MultiLineString and MultiPolygon for modelling geometries corresponding to collections of Points, LineStrings
and Polygons, respectively. MultiCurve and MultiSurface are introduced as abstract superclasses that
generalize the collection interfaces to handle Curves and Surfaces.
The attributes, methods and assertions for each Geometry class are described in Figure 1 in 6.1.1. In
describing methods, this is used to refer to the receiver of the method (the object being messaged).
The SFA COM function “signatures” may use a different notation from SFA SQL. COM notation is more
familiar for COM programmers. However, UML notation is used throughout this part of ISO 19125. There may
also be methods used in this International Standard that differ from one part to another. Where this is the case,
the differences are shown within the part.
This part of ISO 19125 implements a profile of the spatial schema described in ISO 19107:2003, Geographic
information Spatial schema. Annex A provides a detailed mapping of the schema in this part of ISO 19125
with the schema described in ISO 19107:2003.
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SIST EN ISO 19125-1:2006
INTERNATIONAL STANDARD ISO 19125-1:2004(E)
Geographic information — Simple feature access —
Part 1:
Common architecture
1 Scope
This part of ISO 19125 establishes a common architecture and defines terms to use within the architecture.
This part of ISO 19125 does not attempt to standardize and does not depend upon any part of the mechanism
by which Types are added and maintained, including the following:
a) syntax and functionality provided for defining types;
b) syntax and functionality provided for defining functions;
c) physical storage of type instances in the database;
d) specific terminology used to refer to User Defined Types, for example UDT.
This part of ISO 19125 does standardize names and geometric definitions for Types for Geometry.
This part of ISO 19125 does not place any requirements on how to define the Geometry Types in the internal
schema nor does it place any requirements on when or how or who defines the Geometry Types.
2 Conformance
In order to conform to this part of ISO 19125, an implementation shall satisfy the requirements of one or more
test suites specified in the other parts of ISO 19125.
3 Normative references
The following referenced documents are indispensable for the application of this document. For dated
references, only the edition cited applies. For undated references, the latest edition of the referenced
document (including any amendments) applies.
ISO 19107:2003, Geographic information Spatial schema
ISO 19111:2003, Geographic information Spatial referencing by coordinates
4 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
4.1
boundary
set that represents the limit of an entity
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SIST EN ISO 19125-1:2006
ISO 19125-1:2004(E)
NOTE Boundary is most commonly used in the context of geometry, where the set is a collection of points or a
collection of objects that represent those points. In other arenas, the term is used metaphorically to describe the transition
between an entity and the rest of its domain of discourse.
[ISO 19107]
4.2
buffer
geometric object (4.14) that contains all direct positions (4.7) whose distance from a specified geometric
object is less than or equal to a given distance
[ISO 19107]
4.3
coordinate
one of a sequence of n-numbers designating the position of a point (4.17) in n-dimensional space
NOTE In a coordinate reference system, the numbers must be qualified by units.
[adapted from ISO 19111]
4.4
coordinate dimension
number of measurements or axes needed to describe a position in a coordinate system (4.6)
[ISO 19107]
4.5
coordinate reference system
coordinate system (4.6) that is related to the real world by a datum
[adapted from ISO 19111]
4.6
coordinate system
set of mathematical rules for specifying how coordinates (4.3) are to be assigned to point (4.17)
[ISO 19111]
4.7
curve
1-dimensional geometric primitive (4.15), representing the continuous image of a line
NOTE The boundary of a curve is the set of points at either end of the curve. If the curve is a cycle, the two ends are
identical, and the curve (if topologically closed) is considered to not have a boundary. The first point is called the start
point, and the last is the end point. Connectivity of the curve is guaranteed by the “continuous image of a line” clause.
A topological theorem states that a continuous image of a connected set is connected.
[ISO 19107]
4.7
direct position
position described by a single set of coordinates (4.3) within a coordinate reference system (4.5)
[ISO 19107]
4.9
end point
last point (4.17) of a curve (4.7)
[ISO 19107]
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ISO 19125-1:2004(E)
4.10
exterior
difference between the universe and the closure
NOTE The concept of exterior is applicable to both topological and geometric complexes.
[ISO 19107]
4.11
feature
abstraction of real world phenomena
NOTE A feature may occur as a type or an instance. Feature type or feature instance is used when only one is meant.
[adapted from ISO 19101]
4.12
feature attribute
characteristic of a feature (4.11)
NOTE A feature attribute has a name, a data type, and a value domain associated to it. A feature attribute for a
feature instance also has an attribute value taken from the value domain.
[adapted from ISO 19101]
4.13
geometric complex
set of disjoint geometric primitives (4.15) where the boundary (4.1) of each geometric primitive can be
represented as the union of other geometric primitives of smaller dimension within the same set
NOTE The geometric primitives in the set are disjoint in the sense that no direct position is interior to more than one
geometric primitive. The set is closed under boundary operations, meaning that for each element in the geometric complex,
there is a collection (also a geometric complex) of geometric primitives that represents the boundary of that element.
Recall that the boundary of a point (the only 0D primitive object type in geometry) is empty. Thus, if the largest dimension
geometric primitive is a solid (3D), the composition of the boundary operator in this definition terminates after at most
3 steps. It is also the case that the boundary of any object is a cycle.
[ISO 19107]
4.14
geometric object
spatial object representing a geometric set
NOTE A geometric object consists of a geometric primitive, a collection of geometric primitives, or a geometric
complex treated as a single entity. A geometric object may be the spatial representation of an object such as a feature or a
significant part of a feature.
[ISO 19107]
4.15
geometric primitive
geometric object (4.14) representing a single, connected, homogeneous element of space
NOTE Geometric primitives are non-decomposed objects that represent information about geometric configuration.
They include points, curves, surfaces, and solids.
[ISO 19107]
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ISO 19125-1:2004(E)
4.16
interior
set of all direct positions (4.7) that are on a geometric object (4.14) but which are not on its boundary (4.1)
NOTE The interior of a topological object is the homomorphic image of the interior of any of its geometric realizations.
This is not included as a definition because it follows from a theorem of topology.
[ISO 19107]
4.17
point
0-dimensional geometric primitive (4.15), representing a position
NOTE The boundary of a point is the empty set.
[ISO 19107]
4.18
simple feature
feature (4.11) restricted to 2D geometry with linear interpolation between vertices, having both spatial and
non spatial attributes
4.19
start point
first point (4.17) of a curve (4.7)
[ISO 19107]
4.20
surface
2-dimensional geometric primitive (4.15), locally representing a continuous image of a region of a plane
NOTE The boundary of a surface is the set of oriented, closed curves that delineate the limits of the surface.
[adapted from ISO 19107]
5 Abbreviated terms
API Application Program Interface
COM Component Object Model
CORBA Common Object Request Broker Architecture
DCE Distributed Computing Environment
DCOM Distributed Component Objected Model
DE-9IM Dimensionally Extended Nine-Intersection Model
IEEE Institute of Electrical and Electronics Engineers, Inc.
NDR Little Endian byte order encoding
OLE Object Linking and Embedding
RPC Remote Procedure Call
SQL Structured Query Language
4 © ISO 2004 – All rights reserved
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SIST EN ISO 19125-1:2006
ISO 19125-1:2004(E)
SRID Spatial Reference System Identifier
XDR Big Endian byte order encoding
UDT User Defined Type
UML Unified Modeling Language
WKB Well-Known Binary (representation for example, geometry)
6 Architecture
6.1 Geometry object model
6.1.1 Overview
This subclause describes the object model for simple feature geometry. The simple feature geometry object
model is Distributed Computing Platform neutral and uses UML notation. The object model for geometry
is shown in Figure 1. The base Geometry class has subclasses for Point, Curve, Surface and
GeometryCollection. Each geometric object is associated with a Spatial Reference System, which describes
the coordinate space in which the geometric object is defined.
Figure 1 — Geometry class hierarchy
Figure 1 is based on an extended Geometry model with specialized 0-, 1- and 2-dimensional collection
classes named MultiPoint, MultiLineString and MultiPolygon for modelling geometries corresponding to
collections of Points, LineStrings and Polygons, respectively. MultiCurve and MultiSurface are introduced as
abstract superclasses that generalize the collection interfaces to handle Curves and Surfaces. Figure 1 shows
aggregation lines between the leaf-collection classes and their element classes; the aggregation lines for
non-leaf-collection classes are described in the text.
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ISO 19125-1:2004(E)
The attributes, methods and assertions for each Geometry class are described below. In describing methods,
this is used to refer to the receiver of the method (the object being messaged).
6.1.2 Geometry
6.1.2.1 Description
Geometry is the root class of the hierarchy. Geometry is an abstract (non-instantiable) class.
The instantiable subclasses of Geometry defined in this International Standard are restricted to 0, 1 and
2
2-dimensional geometric objects that exist in 2-dimensional coordinate space (ℜ ).
All instantiable Geometry classes described in this part of ISO 19125 are defined so that valid instances of a
Geometry class are topologically closed, i.e. all defined geometries include their boundary.
6.1.2.2 Basic methods on geometric objects
Dimension ( ):Integer — The inherent dimension of this geometric object, which must be less than or
equal to the coordinate dimension. This specification is restricted to geometries in 2-dimensional
coordinate space.
GeometryType ( ):String — Returns the name of the instantiable subtype of Geometry of which this
geometric object is a instantiable member. The name of the subtype of Geometry is returned as a string.
SRID ( ):Integer — Returns the Spatial Reference System ID for this geometric object.
Envelope( ):Geometry — The minimum bounding box for this Geometry, returned as a Geometry. The
polygon is defined by the corner points of the bounding box [(MINX, MINY), (MAXX, MINY), (MAXX,
MAXY), (MINX, MAXY), (MINX, MINY)].
AsText( ):String — Exports this geometric object to a specific Well-known Text Representation of
Geometry.
AsBinary( ):Binary — Exports this geometric object to a specific Well-known Binary Representation of
Geometry.
IsEmpty( ):Integer — Returns 1 (TRUE) if this geometric object is the empty Geometry. If true, then this
geometric object represents the empty point set, ∅, for the coordinate space.
IsSimple( ):Integer — Returns 1 (TRUE) if this geometric object has no anomalous geometric points,
such as self intersection or self tangency. The description of each instantiable geometric class will include
the specific conditions that cause an instance of that class to be classified as not simple.
Boundary( ):Geometry — Returns the closure of the combinatorial boundary of this geometric object
(Reference [1], section 3.12.2). Because the result of this function is a closure, and hence topologically
closed, the resulting boundary can be represented using representational Geometry primitives
(Reference [1], section 3.12.2).
6.1.2.3 Methods for testing spatial relations between geometric objects
The methods in this subclause are defined and described in more detail following the description of the sub-
types of Geometry.
Equals(anotherGeometry:Geometry):Integer — Returns 1 (TRUE) if this geometric object is “spatially
equal” to anotherGeometry.
Disjoint(anotherGeometry:Geometry):Integer — Returns 1 (TRUE) if this geometric object is “spatially
disjoint” from anotherGeometry.
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ISO 19125-1:2004(E)
Intersects(anotherGeometry:Geometry):Integer — Returns 1 (TRUE) if this geometric object “spatially
intersects” anotherGeometry.
Touches(anotherGeometry:Geometry):Integer — Returns 1 (TRUE) if this geometric object “spatially
touches” anotherGeometry.
Crosses(anotherGeometry:Geometry):Integer — Returns 1 (TRUE) if this geometric object “spatially
crosses’ anotherGeometry.
Within(anotherGeometry:Geometry):Integer — Returns 1 (TRUE) if this geometric object is “spatially
within” anotherGeometry.
Contains(anotherGeometry:Geometry):Integer — Returns 1 (TRUE) if this geometric object “spatially
contains” anotherGeometry.
Overlaps(anotherGeometry:Geometry):Integer — Returns 1 (TRUE) if this geometric object “spatially
overlaps” anotherGeometry.
Relate(anotherGeometry:Geometry, intersectionPatternMatrix:String):Integer — Returns 1 (TRUE) if this
geometric object is spatially related to anotherGeometry by testing for intersections between the interior,
boundary and exterior of the two geometric objects as specified by the values in the
intersectionPatternMatrix.
6.1.2.4 Methods that support spatial analysis
Distance(anotherGeometry:Geometry):Double — Returns the shortest distance between any two Points
in the two geometric objects as calculated in the spatial reference system of this geometric object.
Buffer(distance:Double):Geometry — Returns a geometric object that represents all Points whose
distance from this geometric object is less than or equal to distance. Calculations are in the spatial
reference system of this geometric object.
ConvexHull( ):Geometry — Returns a geometric object that represents the convex hull of this geometric
object.
Intersection(anotherGeometry:Geometry):Geometry — Returns a geometric object that represents the
Point set intersection of this geometric object with anotherGeometry.
Union(anotherGeometry:Geometry):Geometry — Returns a geometric object that represents the Point
set union of this geometric object with anotherGeometry.
Difference(anotherGeometry:Geometry):Geometry — Returns a geometric object that represents the
Point set difference of this geometric object with anotherGeometry.
SymDifference(anotherGeometry:Geometry):Geometry — Returns a geometric object that represents
the Point set symmetric difference of this geometric object with anotherGeometry.
6.1.3 GeometryCollection
6.1.3.1 Description
A GeometryCollection is a geometric object that is a collection of 1 or more geometric objects.
All the elements in a GeometryCollection shall be in the same Spatial Reference. This is also the Spatial
Reference for the GeometryCollection.
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SIST EN ISO 19125-1:2006
ISO 19125-1:2004(E)
GeometryCollection places no other constraints on its elements. Subclasses of GeometryCollection may
restrict membership based on dimension and may also place other constraints on the degree of spatial
overlap between elements.
6.1.3.2 Methods
NumGeometries( ):Integer — Returns the number of geometries in this GeometryCollection.
GeometryN(N:integer):Geometry — Returns the Nth geometry in this GeometryCollection.
6.1.4 Point
6.1.4.1 Description
A Point is a 0-dimensional geometric object and represents a single location in coordinate space. A Point has
an x-coordinate value and a y-coordinate value.
The boundary of a Point is the empty set.
6.1.4.2 Methods
X( ):Double — The x-coordinate value for this Point.
Y( ):Double — The y-coordinate value for this Point.
6.1.5 MultiPoint
A MultiPoint is a 0-dimensional GeometryCollection. The elements of a MultiPoint are restricted to Points. The
Points are not connected or ordered.
A MultiPoint is simple if no two Points in the MultiPoint are equal (have identical coordinate values).
The boundary of a MultiPoint is the empty set.
6.1.6 Curve
6.1.6.1 Description
A Curve is a 1-dimensional geometric object usually stored as a sequence of Points, with the subtype of
Curve specifying the form of the interpolation between Points. This part of ISO 19125 defines only one
subclass of Curve, LineString, which uses linear interpolation between Points.
A Curve is a 1-dimensional geometric object that is the homeomorphic image of a real, closed, interval D = [a,
2
b] = {x ∈ ℜ. a u x u b} under a mapping f:[a,b] → ℜ .
A Curve is simple if it does not pass through the same Point twice (Reference [1], section 3.12.7.3):
∀ c ∈ Curve, [a, b] = c.Domain,
c.IsSimple⇔ (∀ x1, x2 ∈ (a, b] x1 ≠ x2 ⇒ f(x1) ≠ f (x2)) ∧ (∀ x1, x2 ∈ [a, b) x1 ≠ x2 ⇒ f(x1) ≠ f(x2))
A Curve is closed if its start Point is equal to its end Point (Reference [1], section 3.12.7.3).
The boundary of a closed Curve is empty.
A Curve that is simple and closed is a Ring.
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ISO 19125-1:2004(E)
The boundary of a non-closed Curve consists of its two end Points (Reference [1], section 3.12.3.2).
A Curve is defined as topologically closed.
6.1.6.2 Methods
Length( ):Double — The length of this Curve in its associated spatial reference.
StartPoint( ):Point — The start Point of this Curve.
EndPoint(
...
SLOVENSKI STANDARD
SIST EN ISO 19125-1:2006
01-junij-2006
Geografske informacije - Dostop do enostavnih pojavov - 1. del: Skupna
arhitektura (ISO 19125-1:2004)
Geographic information - Simple feature access - Part 1: Common architecture (ISO
19125-1:2004)
Geoinformation - Simple feature access - Teil 1 : Gemeinsame Architektur (ISO 19125-
1:2004)
Information géographique - Acces aux entités simples - Partie 1: Architecture commune
(ISO 19125-1:2004)
Ta slovenski standard je istoveten z: EN ISO 19125-1:2006
ICS:
35.240.70 Uporabniške rešitve IT v IT applications in science
znanosti
SIST EN ISO 19125-1:2006 en
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
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SIST EN ISO 19125-1:2006
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SIST EN ISO 19125-1:2006
EUROPEAN STANDARD
EN ISO 19125-1
NORME EUROPÉENNE
EUROPÄISCHE NORM
March 2006
ICS 35.240.70
English Version
Geographic information - Simple feature access - Part 1:
Common architecture (ISO 19125-1:2004)
Information géographique - Accès aux entités simples - Geoinformation - Simple feature access - Teil 1 :
Partie 1: Architecture commune (ISO 19125-1:2004) Gemeinsame Architektur (ISO 19125-1:2004)
This European Standard was approved by CEN on 16 February 2006.
CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this European
Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical references concerning such national
standards may be obtained on application to the Central Secretariat or to any CEN member.
This European Standard exists in three official versions (English, French, German). A version in any other language made by translation
under the responsibility of a CEN member into its own language and notified to the Central Secretariat has the same status as the official
versions.
CEN members are the national standards bodies of Austria, Belgium, Cyprus, Czech Republic, Denmark, Estonia, Finland, France,
Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania,
Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION
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© 2006 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 19125-1:2006: E
worldwide for CEN national Members.
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SIST EN ISO 19125-1:2006
EN ISO 19125-1:2006 (E)
Foreword
The text of ISO 19125-1:2004 has been prepared by Technical Committee ISO/TC 211
"Geographic information/Geomatics” of the International Organization for Standardization (ISO)
and has been taken over as EN ISO 19125-1:2006 by Technical Committee CEN/TC 287
"Geographic Information", the secretariat of which is held by NEN.
This European Standard shall be given the status of a national standard, either by publication of
an identical text or by endorsement, at the latest by September 2006, and conflicting national
standards shall be withdrawn at the latest by September 2006.
According to the CEN/CENELEC Internal Regulations, the national standards organizations of
the following countries are bound to implement this European Standard: Austria, Belgium,
Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary,
Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland,
Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom.
Endorsement notice
The text of ISO 19125-1:2004 has been approved by CEN as EN ISO 19125-1:2006 without any
modifications.
2
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SIST EN ISO 19125-1:2006
INTERNATIONAL ISO
STANDARD 19125-1
First edition
2004-08-01
Geographic information — Simple feature
access —
Part 1:
Common architecture
Information géographique — Accès aux entités simples —
Partie 1: Architecture commune
Reference number
ISO 19125-1:2004(E)
©
ISO 2004
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SIST EN ISO 19125-1:2006
ISO 19125-1:2004(E)
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ii © ISO 2004 – All rights reserved
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SIST EN ISO 19125-1:2006
ISO 19125-1:2004(E)
Contents Page
Foreword. iv
Introduction . v
1 Scope. 1
2 Conformance . 1
3 Normative references . 1
4 Terms and definitions. 1
5 Abbreviated terms. 4
6 Architecture . 5
6.1 Geometry object model . 5
6.2 Well-known Text Representation for Geometry. 21
6.3 Well-known Binary Representation for Geometry. 22
6.4 Well-known Text Representation of Spatial Reference Systems. 25
Annex A (informative) The correspondence of concepts of the common architecture with
concepts of the geometry model of ISO 19107. 28
Annex B (informative) Supported spatial reference data . 36
Bibliography . 42
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SIST EN ISO 19125-1:2006
ISO 19125-1:2004(E)
Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards bodies
(ISO member bodies). The work of preparing International Standards is normally carried out through ISO
technical committees. Each member body interested in a subject for which a technical committee has been
established has the right to be represented on that committee. International organizations, governmental and
non-governmental, in liaison with ISO, also take part in the work. ISO collaborates closely with the
International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization.
International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 2.
The main task of technical committees is to prepare International Standards. Draft International Standards
adopted by the technical committees are circulated to the member bodies for voting. Publication as an
International Standard requires approval by at least 75 % of the member bodies casting a vote.
Attention is drawn to the possibility that some of the elements of this document may be the subject of patent
rights. ISO shall not be held responsible for identifying any or all such patent rights.
ISO 19125-1 was prepared by Technical Committee ISO/TC 211, Geographic information/Geomatics from a
base document supplied by the Open GIS Consortium, Inc.
ISO 19125 consists of the following parts, under the general title Geographic information — Simple feature
access:
— Part 1: Common architecture
— Part 2: SQL option
A Part 3: COM/OLE option is under preparation.
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SIST EN ISO 19125-1:2006
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Introduction
This part of ISO 19125 describes the common architecture for simple feature geometry. The simple feature
geometry object model is Distributed Computing Platform neutral and uses UML notation. The base Geometry
class has subclasses for Point, Curve, Surface and GeometryCollection. Each geometric object is associated
with a Spatial Reference System, which describes the coordinate space in which the geometric object is
defined.
The extended Geometry model has specialized 0, 1 and 2-dimensional collection classes named MultiPoint,
MultiLineString and MultiPolygon for modelling geometries corresponding to collections of Points, LineStrings
and Polygons, respectively. MultiCurve and MultiSurface are introduced as abstract superclasses that
generalize the collection interfaces to handle Curves and Surfaces.
The attributes, methods and assertions for each Geometry class are described in Figure 1 in 6.1.1. In
describing methods, this is used to refer to the receiver of the method (the object being messaged).
The SFA COM function “signatures” may use a different notation from SFA SQL. COM notation is more
familiar for COM programmers. However, UML notation is used throughout this part of ISO 19125. There may
also be methods used in this International Standard that differ from one part to another. Where this is the case,
the differences are shown within the part.
This part of ISO 19125 implements a profile of the spatial schema described in ISO 19107:2003, Geographic
information Spatial schema. Annex A provides a detailed mapping of the schema in this part of ISO 19125
with the schema described in ISO 19107:2003.
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SIST EN ISO 19125-1:2006
INTERNATIONAL STANDARD ISO 19125-1:2004(E)
Geographic information — Simple feature access —
Part 1:
Common architecture
1 Scope
This part of ISO 19125 establishes a common architecture and defines terms to use within the architecture.
This part of ISO 19125 does not attempt to standardize and does not depend upon any part of the mechanism
by which Types are added and maintained, including the following:
a) syntax and functionality provided for defining types;
b) syntax and functionality provided for defining functions;
c) physical storage of type instances in the database;
d) specific terminology used to refer to User Defined Types, for example UDT.
This part of ISO 19125 does standardize names and geometric definitions for Types for Geometry.
This part of ISO 19125 does not place any requirements on how to define the Geometry Types in the internal
schema nor does it place any requirements on when or how or who defines the Geometry Types.
2 Conformance
In order to conform to this part of ISO 19125, an implementation shall satisfy the requirements of one or more
test suites specified in the other parts of ISO 19125.
3 Normative references
The following referenced documents are indispensable for the application of this document. For dated
references, only the edition cited applies. For undated references, the latest edition of the referenced
document (including any amendments) applies.
ISO 19107:2003, Geographic information Spatial schema
ISO 19111:2003, Geographic information Spatial referencing by coordinates
4 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
4.1
boundary
set that represents the limit of an entity
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NOTE Boundary is most commonly used in the context of geometry, where the set is a collection of points or a
collection of objects that represent those points. In other arenas, the term is used metaphorically to describe the transition
between an entity and the rest of its domain of discourse.
[ISO 19107]
4.2
buffer
geometric object (4.14) that contains all direct positions (4.7) whose distance from a specified geometric
object is less than or equal to a given distance
[ISO 19107]
4.3
coordinate
one of a sequence of n-numbers designating the position of a point (4.17) in n-dimensional space
NOTE In a coordinate reference system, the numbers must be qualified by units.
[adapted from ISO 19111]
4.4
coordinate dimension
number of measurements or axes needed to describe a position in a coordinate system (4.6)
[ISO 19107]
4.5
coordinate reference system
coordinate system (4.6) that is related to the real world by a datum
[adapted from ISO 19111]
4.6
coordinate system
set of mathematical rules for specifying how coordinates (4.3) are to be assigned to point (4.17)
[ISO 19111]
4.7
curve
1-dimensional geometric primitive (4.15), representing the continuous image of a line
NOTE The boundary of a curve is the set of points at either end of the curve. If the curve is a cycle, the two ends are
identical, and the curve (if topologically closed) is considered to not have a boundary. The first point is called the start
point, and the last is the end point. Connectivity of the curve is guaranteed by the “continuous image of a line” clause.
A topological theorem states that a continuous image of a connected set is connected.
[ISO 19107]
4.7
direct position
position described by a single set of coordinates (4.3) within a coordinate reference system (4.5)
[ISO 19107]
4.9
end point
last point (4.17) of a curve (4.7)
[ISO 19107]
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4.10
exterior
difference between the universe and the closure
NOTE The concept of exterior is applicable to both topological and geometric complexes.
[ISO 19107]
4.11
feature
abstraction of real world phenomena
NOTE A feature may occur as a type or an instance. Feature type or feature instance is used when only one is meant.
[adapted from ISO 19101]
4.12
feature attribute
characteristic of a feature (4.11)
NOTE A feature attribute has a name, a data type, and a value domain associated to it. A feature attribute for a
feature instance also has an attribute value taken from the value domain.
[adapted from ISO 19101]
4.13
geometric complex
set of disjoint geometric primitives (4.15) where the boundary (4.1) of each geometric primitive can be
represented as the union of other geometric primitives of smaller dimension within the same set
NOTE The geometric primitives in the set are disjoint in the sense that no direct position is interior to more than one
geometric primitive. The set is closed under boundary operations, meaning that for each element in the geometric complex,
there is a collection (also a geometric complex) of geometric primitives that represents the boundary of that element.
Recall that the boundary of a point (the only 0D primitive object type in geometry) is empty. Thus, if the largest dimension
geometric primitive is a solid (3D), the composition of the boundary operator in this definition terminates after at most
3 steps. It is also the case that the boundary of any object is a cycle.
[ISO 19107]
4.14
geometric object
spatial object representing a geometric set
NOTE A geometric object consists of a geometric primitive, a collection of geometric primitives, or a geometric
complex treated as a single entity. A geometric object may be the spatial representation of an object such as a feature or a
significant part of a feature.
[ISO 19107]
4.15
geometric primitive
geometric object (4.14) representing a single, connected, homogeneous element of space
NOTE Geometric primitives are non-decomposed objects that represent information about geometric configuration.
They include points, curves, surfaces, and solids.
[ISO 19107]
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4.16
interior
set of all direct positions (4.7) that are on a geometric object (4.14) but which are not on its boundary (4.1)
NOTE The interior of a topological object is the homomorphic image of the interior of any of its geometric realizations.
This is not included as a definition because it follows from a theorem of topology.
[ISO 19107]
4.17
point
0-dimensional geometric primitive (4.15), representing a position
NOTE The boundary of a point is the empty set.
[ISO 19107]
4.18
simple feature
feature (4.11) restricted to 2D geometry with linear interpolation between vertices, having both spatial and
non spatial attributes
4.19
start point
first point (4.17) of a curve (4.7)
[ISO 19107]
4.20
surface
2-dimensional geometric primitive (4.15), locally representing a continuous image of a region of a plane
NOTE The boundary of a surface is the set of oriented, closed curves that delineate the limits of the surface.
[adapted from ISO 19107]
5 Abbreviated terms
API Application Program Interface
COM Component Object Model
CORBA Common Object Request Broker Architecture
DCE Distributed Computing Environment
DCOM Distributed Component Objected Model
DE-9IM Dimensionally Extended Nine-Intersection Model
IEEE Institute of Electrical and Electronics Engineers, Inc.
NDR Little Endian byte order encoding
OLE Object Linking and Embedding
RPC Remote Procedure Call
SQL Structured Query Language
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SRID Spatial Reference System Identifier
XDR Big Endian byte order encoding
UDT User Defined Type
UML Unified Modeling Language
WKB Well-Known Binary (representation for example, geometry)
6 Architecture
6.1 Geometry object model
6.1.1 Overview
This subclause describes the object model for simple feature geometry. The simple feature geometry object
model is Distributed Computing Platform neutral and uses UML notation. The object model for geometry
is shown in Figure 1. The base Geometry class has subclasses for Point, Curve, Surface and
GeometryCollection. Each geometric object is associated with a Spatial Reference System, which describes
the coordinate space in which the geometric object is defined.
Figure 1 — Geometry class hierarchy
Figure 1 is based on an extended Geometry model with specialized 0-, 1- and 2-dimensional collection
classes named MultiPoint, MultiLineString and MultiPolygon for modelling geometries corresponding to
collections of Points, LineStrings and Polygons, respectively. MultiCurve and MultiSurface are introduced as
abstract superclasses that generalize the collection interfaces to handle Curves and Surfaces. Figure 1 shows
aggregation lines between the leaf-collection classes and their element classes; the aggregation lines for
non-leaf-collection classes are described in the text.
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The attributes, methods and assertions for each Geometry class are described below. In describing methods,
this is used to refer to the receiver of the method (the object being messaged).
6.1.2 Geometry
6.1.2.1 Description
Geometry is the root class of the hierarchy. Geometry is an abstract (non-instantiable) class.
The instantiable subclasses of Geometry defined in this International Standard are restricted to 0, 1 and
2
2-dimensional geometric objects that exist in 2-dimensional coordinate space (ℜ ).
All instantiable Geometry classes described in this part of ISO 19125 are defined so that valid instances of a
Geometry class are topologically closed, i.e. all defined geometries include their boundary.
6.1.2.2 Basic methods on geometric objects
Dimension ( ):Integer — The inherent dimension of this geometric object, which must be less than or
equal to the coordinate dimension. This specification is restricted to geometries in 2-dimensional
coordinate space.
GeometryType ( ):String — Returns the name of the instantiable subtype of Geometry of which this
geometric object is a instantiable member. The name of the subtype of Geometry is returned as a string.
SRID ( ):Integer — Returns the Spatial Reference System ID for this geometric object.
Envelope( ):Geometry — The minimum bounding box for this Geometry, returned as a Geometry. The
polygon is defined by the corner points of the bounding box [(MINX, MINY), (MAXX, MINY), (MAXX,
MAXY), (MINX, MAXY), (MINX, MINY)].
AsText( ):String — Exports this geometric object to a specific Well-known Text Representation of
Geometry.
AsBinary( ):Binary — Exports this geometric object to a specific Well-known Binary Representation of
Geometry.
IsEmpty( ):Integer — Returns 1 (TRUE) if this geometric object is the empty Geometry. If true, then this
geometric object represents the empty point set, ∅, for the coordinate space.
IsSimple( ):Integer — Returns 1 (TRUE) if this geometric object has no anomalous geometric points,
such as self intersection or self tangency. The description of each instantiable geometric class will include
the specific conditions that cause an instance of that class to be classified as not simple.
Boundary( ):Geometry — Returns the closure of the combinatorial boundary of this geometric object
(Reference [1], section 3.12.2). Because the result of this function is a closure, and hence topologically
closed, the resulting boundary can be represented using representational Geometry primitives
(Reference [1], section 3.12.2).
6.1.2.3 Methods for testing spatial relations between geometric objects
The methods in this subclause are defined and described in more detail following the description of the sub-
types of Geometry.
Equals(anotherGeometry:Geometry):Integer — Returns 1 (TRUE) if this geometric object is “spatially
equal” to anotherGeometry.
Disjoint(anotherGeometry:Geometry):Integer — Returns 1 (TRUE) if this geometric object is “spatially
disjoint” from anotherGeometry.
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Intersects(anotherGeometry:Geometry):Integer — Returns 1 (TRUE) if this geometric object “spatially
intersects” anotherGeometry.
Touches(anotherGeometry:Geometry):Integer — Returns 1 (TRUE) if this geometric object “spatially
touches” anotherGeometry.
Crosses(anotherGeometry:Geometry):Integer — Returns 1 (TRUE) if this geometric object “spatially
crosses’ anotherGeometry.
Within(anotherGeometry:Geometry):Integer — Returns 1 (TRUE) if this geometric object is “spatially
within” anotherGeometry.
Contains(anotherGeometry:Geometry):Integer — Returns 1 (TRUE) if this geometric object “spatially
contains” anotherGeometry.
Overlaps(anotherGeometry:Geometry):Integer — Returns 1 (TRUE) if this geometric object “spatially
overlaps” anotherGeometry.
Relate(anotherGeometry:Geometry, intersectionPatternMatrix:String):Integer — Returns 1 (TRUE) if this
geometric object is spatially related to anotherGeometry by testing for intersections between the interior,
boundary and exterior of the two geometric objects as specified by the values in the
intersectionPatternMatrix.
6.1.2.4 Methods that support spatial analysis
Distance(anotherGeometry:Geometry):Double — Returns the shortest distance between any two Points
in the two geometric objects as calculated in the spatial reference system of this geometric object.
Buffer(distance:Double):Geometry — Returns a geometric object that represents all Points whose
distance from this geometric object is less than or equal to distance. Calculations are in the spatial
reference system of this geometric object.
ConvexHull( ):Geometry — Returns a geometric object that represents the convex hull of this geometric
object.
Intersection(anotherGeometry:Geometry):Geometry — Returns a geometric object that represents the
Point set intersection of this geometric object with anotherGeometry.
Union(anotherGeometry:Geometry):Geometry — Returns a geometric object that represents the Point
set union of this geometric object with anotherGeometry.
Difference(anotherGeometry:Geometry):Geometry — Returns a geometric object that represents the
Point set difference of this geometric object with anotherGeometry.
SymDifference(anotherGeometry:Geometry):Geometry — Returns a geometric object that represents
the Point set symmetric difference of this geometric object with anotherGeometry.
6.1.3 GeometryCollection
6.1.3.1 Description
A GeometryCollection is a geometric object that is a collection of 1 or more geometric objects.
All the elements in a GeometryCollection shall be in the same Spatial Reference. This is also the Spatial
Reference for the GeometryCollection.
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GeometryCollection places no other constraints on its elements. Subclasses of GeometryCollection may
restrict membership based on dimension and may also place other constraints on the degree of spatial
overlap between elements.
6.1.3.2 Methods
NumGeometries( ):Integer — Returns the number of geometries in this GeometryCollection.
GeometryN(N:integer):Geometry — Returns the Nth geometry in this GeometryCollection.
6.1.4 Point
6.1.4.1 Description
A Point is a 0-dimensional geometric object and represents a single location in coordinate space. A Point has
an x-coordinate value and a y-coordinate value.
The boundary of a Point is the empty set.
6.1.4.2 Methods
X( ):Double — The x-coordinate value for this Point.
Y( ):Double — The y-coordinate value for this Point.
6.1.5 MultiPoint
A MultiPoint is a 0-dimensional GeometryCollection. The elements of a MultiPoint are restricted to Points. The
Points are not connected or ordered.
A MultiPoint is simple if no two Points in the MultiPoint are equal (have identical coordinate values).
The boundary of a MultiPoint is the empty set.
6.1.6 Curve
6.1.6.1 Description
A Curve is a 1-dimensional geometric object usually stored as a sequence of Points, with the subtype of
Curve specifying the form of the interpolation between Points. This part of ISO 19125 defines only one
subclass of Curve, LineString, which uses linear interpolation between Points.
A Curve is a 1-dimensional geometric object that is the homeomorphic image of a real, closed, interval D = [a,
2
b] = {x ∈ ℜ. a u x u b} under a mapping f:[a,b] → ℜ .
A Curve is simple if it does not pass through the same Point twice (Reference [1], section 3.12.7.3):
∀ c ∈ Curve, [a, b] = c.Domain,
c.IsSimple⇔ (∀ x1, x2 ∈ (a, b] x1 ≠ x2 ⇒ f(x1) ≠ f (x2)) ∧ (∀ x1, x2 ∈ [a, b) x1 ≠ x2 ⇒ f(x1) ≠ f(x2))
A Curve is closed if its start Point is equal to its end Point (Reference [1], section 3.12.7.3).
The boundary of a closed Curve is empty.
A Curve that is simple and closed is a Ring.
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The boundary of a non-closed Curve consists of its two end Points (Reference [1], section 3.12.3.2).
A Curve is defined as topologically closed.
6.1.6.2 Methods
Length( ):Double — The length of this Curve in its associated spatial reference.
StartPoint( ):Point — The start Point of this Curve.
EndPoint( ):Point — The end Point of this Curve
...
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