ISO 19123:2005
(Main)Geographic information — Schema for coverage geometry and functions
Geographic information — Schema for coverage geometry and functions
ISO 19123:2005 defines a conceptual schema for the spatial characteristics of coverages. Coverages support mapping from a spatial, temporal or spatiotemporal domain to feature attribute values where feature attribute types are common to all geographic positions within the domain. A coverage domain consists of a collection of direct positions in a coordinate space that may be defined in terms of up to three spatial dimensions as well as a temporal dimension. Examples of coverages include rasters, triangulated irregular networks, point coverages and polygon coverages. Coverages are the prevailing data structures in a number of application areas, such as remote sensing, meteorology and mapping of bathymetry, elevation, soil and vegetation. ISO 19123:2005 defines the relationship between the domain of a coverage and an associated attribute range. The characteristics of the spatial domain are defined whereas the characteristics of the attribute range are not part of ISO 19123:2005.
Information géographique — Schéma de la géométrie et des fonctions de couverture
L'ISO 19123:2005 définit un schéma conceptuel des caractéristiques spatiales des couvertures. Les couvertures servent de base à la cartographie réalisée à partir d'un domaine spatial, temporel ou spatio-emporel permettant ainsi d'obtenir les valeurs attributaires d'entités dont les types d'attributs sont communs à toutes les positions géographiques existant dans le domaine. Un domaine de couverture se compose d'un ensemble de positions directes dans un espace de coordonnées qui peut être défini comme tridimensionnel ou bien temporel. Parmi les exemples de couverture, citons les matrices, les réseaux irréguliers de triangles, les couvertures de points et les couvertures de polygones. Les couvertures sont les structures de données courantes dans divers champs d'application, notamment la télédétection, la météorologie, la bathymétrie, l'altitude, le sol et la végétation. L'ISO 19123:2005 définit la relation entre le domaine d'une couverture et une plage d'attributs associée. Les caractéristiques du domaine spatial sont définies, mais les caractéristiques des attributs ne font pas partie du domaine d'application de l'ISO 19123:2005.
Geografske informacije – Shema za geometrijo podatkovnega sloja in funkcije
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INTERNATIONAL ISO
STANDARD 19123
First edition
2005-08-15
Geographic information — Schema for
coverage geometry and functions
Information géographique — Schéma de la géométrie et des fonctions
de couverture
Reference number
ISO 19123:2005(E)
©
ISO 2005
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ISO 19123:2005(E)
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ii © ISO 2005 – All rights reserved
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ISO 19123:2005(E)
Contents Page
Foreword. v
Introduction . vi
1 Scope . 1
2 Conformance. 1
3 Normative references . 2
4 Terms, definitions, abbreviated terms and notation . 2
4.1 Terms and definitions. 2
4.2 Abbreviated terms . 7
4.3 Notation . 7
5 Fundamental characteristics of coverages.8
5.1 The context for coverages . 8
5.2 The coverage schema . 9
5.3 CV_Coverage. 10
5.4 CV_DomainObject. 13
5.5 CV_AttributeValues . 13
5.6 CV_CommonPointRule. 14
5.7 CV_DiscreteCoverage . 14
5.8 CV_GeometryValuePair. 15
5.9 CV_ContinuousCoverage . 16
5.10 CV_ValueObject . 17
5.11 CV_InterpolationMethod . 18
5.12 Subclasses of CV_ContinuousCoverage . 18
6 Discrete coverages. 18
6.1 Discrete coverage types . 18
6.2 CV_DiscretePointCoverage . 19
6.3 CV_PointValuePair. 20
6.4 CV_DiscreteGridPointCoverage. 20
6.5 CV_GridPointValuePair . 21
6.6 CV_DiscreteCurveCoverage . 21
6.7 CV_CurveValuePair . 22
6.8 CV_DiscreteSurfaceCoverage . 22
6.9 CV_SurfaceValuePair . 24
6.10 CV_DiscreteSolidCoverage . 24
6.11 CV_SolidValuePair. 24
7 Thiessen polygon coverage . 25
7.1 Thiessen polygon networks . 25
7.2 CV_ThiessenPolygonCoverage. 25
7.3 CV_ThiessenValuePolygon . 27
8 Quadrilateral grid coverages . 27
8.1 General. 27
8.2 Quadrilateral grid geometry. 27
8.3 CV_Grid. 30
8.4 CV_GridEnvelope. 31
8.5 CV_GridPoint. 31
8.6 CV_GridCoordinate. 32
8.7 CV_GridCell . 32
8.8 CV_Footprint . 33
8.9 CV_RectifiedGrid . 33
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ISO 19123:2005(E)
8.10 CV_ReferenceableGrid . 34
8.11 CV_ContinousQuadrilateralGridCoverage . 35
8.12 CV_GridValueCell. 36
8.13 CV_GridPointValuePair . 36
8.14 CV_GridValuesMatrix. 37
8.15 CV_SequenceRule . 38
8.16 CV_SequenceType. 38
9 Hexagonal Grid Coverages . 39
9.1 General . 39
9.2 CV_HexagonalGridCoverage . 39
9.3 CV_GridValuesMatrix. 41
9.4 CV_ValueHexagon . 41
10 Triangulated irregular network (TIN) coverages. 41
10.1 General . 41
10.2 CV_TINCoverage . 43
10.3 CV_ValueTriangle. 43
11 Segmented curve coverages . 44
11.1 General . 44
11.2 CV_SegmentedCurveCoverage . 45
11.3 CV_ValueCurve . 45
11.4 CV_ValueSegment . 46
11.5 Evaluation . 46
Annex A (normative) Abstract test suite. 47
Annex B (informative) UML Notation . 51
Annex C (informative) Interpolation methods. 56
Annex D (informative) Sequential enumeration. 60
Bibliography . 65
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ISO 19123:2005(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 19123 was prepared by Technical Committee ISO/TC 211, Geographic information/Geomatics.
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ISO 19123:2005(E)
Introduction
Geographic phenomena fall into two broad categories — discrete and continuous. Discrete phenomena are
recognizable objects that have relatively well-defined boundaries or spatial extent. Examples include buildings,
streams and measurement stations. Continuous phenomena vary over space and have no specific extent.
Examples include temperature, soil composition and elevation. A value or description of a continuous
phenomenon is only meaningful at a particular position in space (and possibly time). Temperature, for
example, takes on specific values only at defined locations, whether measured or interpolated from other
locations.
These concepts are not mutually exclusive. In fact, many components of the landscape may be viewed
alternatively as discrete or continuous. For example, a stream is a discrete entity, but its flow rate and water
quality index vary from one position to another. Similarly, a highway can be thought of as a feature or as a
collection of observations measuring accidents or traffic flow, and an agricultural field is both a spatial object
and a set of measurements of crop yield through time.
Historically, geographic information has been treated in terms of two fundamental types called vector data and
raster data.
“Vector data” deals with discrete phenomena, each of which is conceived of as a feature. The spatial
characteristics of a discrete real-world phenomenon are represented by a set of one or more geometric
primitives (points, curves, surfaces or solids). Other characteristics of the phenomenon are recorded as
feature attributes. Usually, a single feature is associated with a single set of attribute values. ISO 19107:2003
provides a schema for describing features in terms of geometric and topological primitives.
“Raster data”, on the other hand, deals with real-world phenomena that vary continuously over space. It
contains a set of values, each associated with one of the elements in a regular array of points or cells. It is
usually associated with a method for interpolating values at spatial positions between the points or within the
cells. Since this data structure is not the only one that can be used to represent phenomena that vary
continuously over space, this International Standard uses the term “coverage,” adopted from the Abstract
[1]
Specification of the Open GIS Consortium , to refer to any data representation that assigns values directly to
spatial position. A coverage is a function from a spatial, temporal or spatiotemporal domain to an attribute
range. A coverage associates a position within its domain to a record of values of defined data types.
In this International Standard, coverage is a subtype of feature. A coverage is a feature that has multiple
values for each attribute type, where each direct position within the geometric representation of the feature
has a single value for each attribute type.
Just as the concepts of discrete and continuous phenomena are not mutually exclusive, their representations
as discrete features or coverages are not mutually exclusive. The same phenomenon may be represented as
either a discrete feature or a coverage. A city may be viewed as a discrete feature that returns a single value
for each attribute, such as its name, area and total population. The city feature may also be represented as a
coverage that returns values such as population density, land value or air quality index for each position in the
city.
A coverage, moreover, can be derived from a collection of discrete features with common attributes, the
values of the coverage at each position being the values of the attributes of the feature located at that position.
Conversely, a collection of discrete features can be derived from a coverage, each discrete feature being
composed of a set of positions associated with specified attribute values.
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INTERNATIONAL STANDARD ISO 19123:2005(E)
Geographic information — Schema for coverage geometry and
functions
1 Scope
This International Standard defines a conceptual schema for the spatial characteristics of coverages.
Coverages support mapping from a spatial, temporal or spatiotemporal domain to feature attribute values
where feature attribute types are common to all geographic positions within the domain. A coverage domain
consists of a collection of direct positions in a coordinate space that may be defined in terms of up to three
spatial dimensions as well as a temporal dimension. Examples of coverages include rasters, triangulated
irregular networks, point coverages and polygon coverages. Coverages are the prevailing data structures in a
number of application areas, such as remote sensing, meteorology and mapping of bathymetry, elevation, soil
and vegetation. This International Standard defines the relationship between the domain of a coverage and an
associated attribute range. The characteristics of the spatial domain are defined whereas the characteristics of
the attribute range are not part of this standard.
2 Conformance
This International Standard specifies interfaces for several types of coverage objects. In addition, it supports
the interchange of coverage data independently of those interfaces. Thus, it specifies two sets of conformance
classes: one for implementation of the interfaces, the other for the exchange of coverage data. Each set
includes one conformance class for each type of coverage specified in this International Standard (Table 1).
Table 1 — Conformance classes
Conformance class Subclause
Simple coverage interface A.1.1
Discrete coverage interface A.1.2
Thiessen polygon coverage interface A.1.3
Quadrilateral grid coverage interface A.1.4
Hexagonal grid coverage interface A.1.5
TIN coverage interface A.1.6
Segmented curve coverage interface A.1.7
Discrete coverage interchange A.2.1
Thiessen polygon coverage interchange A.2.2
Quadrilateral grid coverage interchange A.2.3
Hexagonal grid coverage interchange A.2.4
TIN coverage interchange A.2.5
Segmented curve coverage interchange A.2.6
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ISO 19123:2005(E)
In general, the interface conformance classes require implementation of all attributes, associations and
operations of relevant classes. This set includes a single conformance class (A.2.1) that supports a simple
interface for evaluation of any coverage type, but exposes none of the internal structure of the coverage. The
remainder of the set are conformance classes that support interfaces to specific coverage types that expose
additional information about the internal structure of the coverage.
The interchange conformance classes require only implementation of the attributes and associations of the
relevant classes.
The Abstract Test Suite in Annex A shows the implementation requirements necessary to conform to this
International Standard. Table 1 lists the subclauses of the Abstract Test Suite that apply for each conformance
class.
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/TS 19103:2005, Geographic information — Conceptual schema language
ISO 19107:2003, Geographic information — Spatial schema
ISO 19108:2002, Geographic information — Temporal schema
ISO 19109:2005, Geographic information — Rules for application schema
ISO 19111:2003, Geographic information — Spatial referencing by coordinates
ISO 19115:2003, Geographic information — Metadata
4 Terms, definitions, abbreviated terms and notation
4.1 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
4.1.1
continuous coverage
coverage that returns different values for the same feature attribute at different direct positions within a
single spatial object, temporal object or spatiotemporal object in its domain
NOTE Although the domain of a continuous coverage is ordinarily bounded in terms of its spatial and/or temporal
extent, it can be subdivided into an infinite number of direct positions.
4.1.2
convex hull
smallest convex set containing a given geometric object
[2]
[adapted from Dictionary of Computing:1996 ]
4.1.3
convex set
geometric set in which any direct position on the straight-line segment joining any two direct positions in
the geometric set is also contained in the geometric set
[2]
[Dictionary of Computing:1996 ]
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ISO 19123:2005(E)
4.1.4
coordinate
one of a sequence of n numbers designating the position of a point in n-dimensional space
[ISO 19111:2003]
4.1.5
coordinate dimension
number of measurements or axes needed to describe a position in a coordinate system
[ISO 19107:2003]
4.1.6
coordinate reference system
coordinate system that is related to the real world by a datum
[ISO 19111:2003]
41.7
coverage
feature that acts as a function to return values from its range for any direct position within its spatial,
temporal or spatiotemporal domain
EXAMPLE Examples include a raster image, polygon overlay or digital elevation matrix.
NOTE In other words, a coverage is a feature that has multiple values for each attribute type, where each direct
position within the geometric representation of the feature has a single value for each attribute type.
4.1.8
coverage geometry
configuration of the domain of a coverage described in terms of coordinates
4.1.9
curve
1-dimensional geometric primitive, representing the continuous image of a line
[ISO 19107:2003]
NOTE The boundary of a curve is the set of points at either end of the curve.
4.1.10
Delaunay triangulation
network of triangles such that the circle passing through the vertices of any triangle does not contain, in its
interior, the vertex of any other triangle
4.1.11
direct position
position described by a single set of coordinates within a coordinate reference system
[ISO 19107:2003]
4.1.12
discrete coverage
coverage that returns the same feature attribute values for every direct position within any single spatial
object, temporal object or spatiotemporal object in its domain
NOTE The domain of a discrete coverage consists of a finite set of spatial, temporal, or spatiotemporal objects.
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ISO 19123:2005(E)
4.1.13
domain
well-defined set
[ISO/TS 19103]
NOTE Domains are used to define the domain and range of operators and functions.
4.1.14
evaluation
〈coverage〉 determination of the values of a coverage at a direct position within the domain of the coverage
4.1.15
feature
0 abstraction of real world phenomena
[ISO 19101]
4.1.16
feature attribute
characteristic of a feature
[ISO 19101]
4.1.17
function
rule that associates each element from a domain (source or domain of the function) to a unique element in
another domain (target, co-domain or range)
[ISO 19107:2003]
4.1.18
geometric object
spatial object representing a geometric set
[ISO 19107:2003]
4.1.19
geometric primitive
geometric object representing a single, connected, homogeneous element of space
[ISO 19107:2003]
4.1.20
geometric set
set of direct positions
[ISO 19107:2003]
4.1.21
geometry value object
object composed of a set of geometry value pairs
4.1.22
geometry value pair
ordered pair composed of a spatial object, a temporal object or a spatiotemporal object and a record of
feature attribute values
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ISO 19123:2005(E)
4.1.23
grid
network composed of two or more sets of curves in which the members of each set intersect the members of
the other sets in an algorithmic way
NOTE The curves partition a space into grid cells.
4.1.24
grid point
point located at the intersection of two or more curves in a grid
4.1.25
inverse evaluation
〈coverage〉 selection of a set of objects from the domain of a coverage based on the feature attribute values
associated with the objects
4.1.26
point
0-dimensional geometric primitive, representing a position
[ISO 19107:2003]
NOTE The boundary of a point is the empty set.
4.1.27
point coverage
coverage that has a domain composed of points
4.1.28
polygon coverage
coverage that has a domain composed of polygons
4.1.29
range
〈coverage〉 set of feature attribute values associated by a function with the elements of the domain of a
coverage
4.1.30
raster
usually rectangular pattern of parallel scanning lines forming or corresponding to the display on a cathode ray
tube
NOTE A raster is a type of grid.
4.1.31
record
finite, named collection of related items (objects or values)
[ISO 19107:2003]
NOTE Logically, a record is a set of pairs .
4.1.32
rectified grid
grid for which there is an affine transformation between the grid coordinates and the coordinates of an
external coordinate reference system
NOTE If the coordinate reference system is related to the earth by a datum, the grid is a georectified grid.
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ISO 19123:2005(E)
4.1.33
referenceable grid
grid associated with a transformation that can be used to convert grid coordinate values to values of
coordinates referenced to an external coordinate reference system
NOTE If the coordinate reference system is related to the earth by a datum, the grid is a georeferenceable grid.
4.1.34
solid
3-dimensional geometric primitive, representing the continuous image of a region of Euclidean 3-space
[ISO 19107:2003]
NOTE A solid is realizable locally as a three-parameter set of direct positions. The boundary of a solid is the set of
oriented, closed surfaces that comprise the limits of the solid.
4.1.35
spatial object
object used for representing a spatial characteristic of a feature
[ISO 19107:2003]
4.1.36
spatiotemporal domain
〈coverage〉 domain composed of spatiotemporal objects
NOTE The spatiotemporal domain of a continuous coverage consists of a set of direct positions defined in relation to
a collection of spatiotemporal objects.
4.1.37
spatiotemporal object
object representing a set of direct positions in space and time
4.1.38
surface
2-dimensional geometric primitive, locally representing a continuous image of a region of a plane
[ISO 19107:2003]
NOTE The boundary of a surface is the set of oriented, closed curves that delineate the limits of the surface.
4.1.39
tessellation
partitioning of a space into a set of conterminous subspaces having the same dimension as the space being
partitioned
NOTE A tessellation composed of congruent regular polygons or polyhedra is a regular tessellation. One composed
of regular,
...
NORME ISO
INTERNATIONALE 19123
Première édition
2005-08-15
Information géographique — Schéma de
la géométrie et des fonctions de
couverture
Geographic information — Schema for coverage geometry and
functions
Numéro de référence
ISO 19123:2005(F)
©
ISO 2005
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ISO 19123:2005(F)
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Version française parue en 2008
Publié en Suisse
ii © ISO 2005 – Tous droits réservés
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ISO 19123:2005(F)
Sommaire Page
Avant-propos. v
Introduction . vi
1 Domaine d'application.1
2 Conformité.1
3 Références normatives .2
4 Termes, définitions, termes abrégés et notation.2
4.1 Termes et définitions.2
4.2 Abréviations .7
4.3 Notation .7
5 Caractéristiques fondamentales des couvertures .8
5.1 Contexte des couvertures.8
5.2 Schéma de couverture .9
5.3 CV_Coverage.10
5.4 CV_DomainObject.13
5.5 CV_AttributeValues .13
5.6 CV_CommonPointRule .14
5.7 CV_DiscreteCoverage .14
5.8 CV_GeometryValuePair.15
5.9 CV_ContinuousCoverage .16
5.10 CV_ValueObject .17
5.11 CV_InterpolationMethod .18
5.12 Sous-classes de CV_ContinuousCoverage .18
6 Couvertures discrètes.19
6.1 Types de couvertures discrètes.19
6.2 CV_DiscretePointCoverage .19
6.3 CV_PointValuePair.20
6.4 CV_DiscreteGridPointCoverage.20
6.5 CV_GridPointValuePair .21
6.6 CV_DiscreteCurveCoverage.21
6.7 CV_CurveValuePair .22
6.8 CV_DiscreteSurfaceCoverage .22
6.9 CV_SurfaceValuePair .24
6.10 CV_DiscreteSolidCoverage .24
6.11 CV_SolidValuePair.24
7 Couverture par polygones de Thiessen .25
7.1 Réseaux de polygones de Thiessen.25
7.2 CV_ThiessenPolygonCoverage.25
7.3 CV_ThiessenValuePolygon .27
8 Couvertures en grilles quadrilatérales .27
8.1 Généralités .27
8.2 Géométrie de la grille quadrilatérale.27
8.3 CV_Grid.30
8.4 CV_GridEnvelope.32
8.5 CV_GridPoint.32
8.6 CV_GridCoordinate.33
8.7 CV_GridCell .33
8.8 CV_Footprint .33
8.9 CV_RectifiedGrid .34
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ISO 19123:2005(F)
8.10 CV_ReferenceableGrid . 35
8.11 CV_ContinousQuadrilateralGridCoverage . 36
8.12 CV_GridValueCell. 37
8.13 CV_GridPointValuePair . 37
8.14 CV_GridValuesMatrix. 38
8.15 CV_SequenceRule . 39
8.16 CV_SequenceType. 39
9 Couvertures en grilles hexagonales . 39
9.1 Généralités. 39
9.2 CV_HexagonalGridCoverage . 40
9.3 CV_GridValuesMatrix. 41
9.4 CV_ValueHexagon . 42
10 Couvertures en réseau irrégulier de triangles (TIN). 42
10.1 Généralités. 42
10.2 CV_TINCoverage . 43
10.3 CV_ValueTriangle. 44
11 Couvertures par courbes segmentées . 44
11.1 Généralités. 44
11.2 CV_SegmentedCurveCoverage . 45
11.3 CV_ValueCurve . 46
11.4 CV_ValueSegment . 47
11.5 Evaluation . 47
Annexe A (normative) Suite d’essais sommaires . 48
Annexe B (informative) Notation UML . 52
Annexe C (informative) Méthodes d’interpolation. 58
Annexe D (informative) Énumération séquentielle. 62
Bibliographie . 67
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ISO 19123:2005(F)
Avant-propos
L'ISO (Organisation internationale de normalisation) est une fédération mondiale d'organismes nationaux de
normalisation (comités membres de l'ISO). L'élaboration des Normes internationales est en général confiée
aux comités techniques de l'ISO. Chaque comité membre intéressé par une étude a le droit de faire partie du
comité technique créé à cet effet. Les organisations internationales, gouvernementales et non
gouvernementales, en liaison avec l'ISO participent également aux travaux. L'ISO collabore étroitement avec
la Commission électrotechnique internationale (CEI) en ce qui concerne la normalisation électrotechnique.
Les Normes internationales sont rédigées conformément aux règles données dans les Directives ISO/CEI,
Partie 2.
La tâche principale des comités techniques est d'élaborer les Normes internationales. Les projets de Normes
internationales adoptés par les comités techniques sont soumis aux comités membres pour vote. Leur
publication comme Normes internationales requiert l'approbation de 75 % au moins des comités membres
votants.
L'attention est appelée sur le fait que certains des éléments du présent document peuvent faire l'objet de
droits de propriété intellectuelle ou de droits analogues. L'ISO ne saurait être tenue pour responsable de ne
pas avoir identifié de tels droits de propriété et averti de leur existence.
L'ISO 19123 a été élaborée par le comité technique ISO/TC 211, Information géographique/Géomatique.
© ISO 2005 – Tous droits réservés v
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ISO 19123:2005(F)
Introduction
Les phénomènes géographiques peuvent être classés en deux grandes catégories: les phénomènes discrets
et les phénomènes continus. Les phénomènes discrets sont des objets identifiables qui présentent des limites
ou une étendue spatiale relativement bien définies. Les constructions, les cours d’eau et les stations de
mesure sont autant de phénomènes qui illustrent cette notion. Les phénomènes continus, quant à eux, se
produisent dans l'espace et n’ont pas d’étendue spécifique. Des éléments tels que la température, la
composition du sol ou l’altitude sont des exemples de phénomènes continus. Une valeur ou une description
d’un phénomène continu est seulement significative à une position particulière dans l’espace (et
éventuellement dans le temps). Les valeurs de la température, par exemple, varient d’un lieu à un autre,
qu’elles soient mesurées ou interpolées à d’autres endroits.
Ces notions ne s’excluent pas les unes les autres. En fait, de nombreux composants du paysage peuvent être
perçus tant de manière discrète que de manière continue. Ainsi, un cours d'eau se définit comme une entité
discrète, cependant le débit et l’indice de la qualité de l’eau varient d'une position à une autre. De la même
manière, une autoroute peut être considérée comme un élément ou un ensemble d'observations permettant
d’évaluer les accidents ou la densité du trafic, et une surface agricole se caractérise tant par une entité
spatiale que comme une série de mesures des rendements de récolte au fil du temps.
L’information a toujours été traitée en deux types fondamentaux: les données vectorielles et les données
matricielles.
Les «données vectorielles» se concentrent sur des phénomènes discrets, chacun d’entre eux étant considéré
comme une entité. Un ou plusieurs ensembles de primitives géométriques (points, courbes, surfaces ou
solides) représentent les caractéristiques spatiales d’un phénomène discret du monde réel. D'autres
caractéristiques du phénomène sont décrites comme des attributs de l’entité. Souvent, une seule entité est
associée à une seule série de valeurs attributaires. L’ISO 19107 fournit un schéma permettant de décrire les
entités en termes de données primitives géométriques et topologiques.
Les «données matricielles» se concentrent, quant à elles, sur les phénomènes réels qui varient en continu
dans l'espace. Elles comprennent un ensemble de valeurs, chacune associée à l’un des éléments dans un
regroupement régulier de points ou de cellules. Elles sont souvent associées à une méthode d'interpolation
des valeurs en des positions spatiales entre les points ou à l’intérieur des cellules. Étant donné qu’il existe
d’autres structures de données permettant de représenter les phénomènes qui varient en continu dans
l'espace, la présente Norme internationale emploie le terme «couverture», emprunté de la spécification
[1]
sommairee de l’Open GIS Consortium , pour se référer à toute représentation de données qui attribue
directement des valeurs à une position spatiale. Une couverture est une fonction qui assigne des attributs
d’un domaine spatial, temporel ou spatio-temporel à une plage d’attributs. Une couverture associe, dans son
domaine, une position à un enregistrement de valeurs de types de données définis.
Dans la présente Norme internationale, le terme «couverture» est un sous-type du terme «entité». Une
couverture est une entité qui prend des valeurs multiples pour chaque type d’attribut, où chaque position
directe dans la représentation géométrique de l’élément a une seule et même valeur pour chaque type
d’attribut.
De même que les concepts de phénomènes discrets et continus, leur représentation en tant qu’entités ou
couvertures discrètes ne s’exclut pas mutuellement. Le même phénomène peut être représenté comme une
entité ou une couverture discrète. Une ville peut être perçue comme une entité discrète à laquelle une seule
valeur est attribuée pour chaque attribut, par exemple le nom, la superficie et la population totale. L’entité
«ville» peut aussi être représentée comme une couverture qui correspond à la densité de population, à la
valeur du terrain ou bien à l’indice de la qualité de l’air en chaque point de la ville.
En outre, une couverture peut résulter d’un ensemble d’entités discrètes aux attributs communs, les valeurs
de la couverture en fonction de chaque position correspondant aux valeurs attributaires d’une entité située à
cette position. À l’inverse, un ensemble d’entités discrètes peut résulter d’une couverture, chacune des entités
discrètes étant composée d’une série de positions associées à des valeurs attributaires spécifiées.
vi © ISO 2005 – Tous droits réservés
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NORME INTERNATIONALE ISO 19123:2005(F)
Information géographique — Schéma de la géométrie
et des fonctions de couverture
1 Domaine d'application
La présente Norme internationale définit un schéma conceptuel des caractéristiques spatiales des
couvertures. Les couvertures servent de base à la cartographie réalisée à partir d’un domaine spatial,
temporel ou spatio-temporel permettant ainsi d’obtenir les valeurs attributaires d’entités dont les types
d’attributs sont communs à toutes les positions géographiques existant dans le domaine. Un domaine de
couverture se compose d’un ensemble de positions directes dans un espace de coordonnées qui peut être
défini comme tridimensionnel ou bien temporel. Parmi les exemples de couverture, citons les matrices, les
réseaux irréguliers de triangles, les couvertures de points et les couvertures de polygones. Les couvertures
sont les structures de données courantes dans divers champs d’application, notamment la télédétection, la
météorologie, la bathymétrie, l’altitude, le sol et la végétation. La présente Norme internationale définit la
relation entre le domaine d’une couverture et une plage d’attributs associée. Les caractéristiques du domaine
spatial sont définies, mais les caractéristiques des attributs ne font pas partie du domaine d’application de la
présente Norme internationale.
2 Conformité
La présente Norme internationale spécifie les interfaces de plusieurs types d’objets de couverture. En outre,
elle prend en charge l’échange de données de couverture indépendamment de ces interfaces. Ainsi, elle
spécifie deux séries de classes de conformité: l’une relative à l’implémentation des interfaces, l’autre
concernant l’échange de données de couverture. Chaque ensemble inclut une classe de conformité pour
chaque type de couverture spécifiée dans la présente Norme internationale (voir Tableau 1).
Tableau 1 — Classes de conformité
Classe de conformité Paragraphe
Interface de couverture simple A.1.1
Interface de couverture discrète A.1.2
Interface de couverture en polygones de Thiessen A.1.3
Interface de couverture en grilles quadrilatérales A.1.4
Interface de couverture en grilles hexagonales A.1.5
Interface de couverture de type TIN A.1.6
Interface de couverture en courbes segmentées A.1.7
Échange de couverture discrète A.2.1
Échange de couverture en polygones de Thiessen A.2.2
Échange de couverture en grilles quadrilatérales A.2.3
Échange de couverture en grilles hexagonales A.2.4
Échange de couverture de type TIN A.2.5
Échange de couverture en courbes segmentées A.2.6
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ISO 19123:2005(F)
De manière générale, les classes de conformité de l’interface requièrent l’implémentation de tous les attributs,
associations et opérations des classes afférentes. Cet ensemble inclut une seule classe de conformité (A.2.1.)
qui prend en charge une interface simple permettant d’évaluer tout type de couverture; toutefois, elle ne
fournit aucune information sur la structure interne de la couverture. Les éléments restants de l’ensemble
correspondent aux classes de conformité qui prennent en charge des interfaces pour des types de couverture
spécifiques fournissant des informations sur la structure interne de la couverture.
Les classes de conformité relatives à «l’échange» nécessitent uniquement l’implémentation des attributs et
des associations des classes y afférentes.
La suite d’essais sommairee de l’Annexe A décrit les exigences relatives à l'implémentation requises pour
permettre la conformité avec la présente Norme internationale. Le Tableau 1 établit une liste des paragraphes
de la suite d’essais sommaires qui s’appliquent pour chaque classe.
3 Références normatives
Les documents de référence suivants sont indispensables à l'application du présent document. Pour les
références datées, seule l’édition citée s’applique. Pour les références non datées, la dernière édition du
document de référence s’applique (y compris les éventuels amendements).
ISO/TS 19103:2005, Information géographique — Schéma de langage conceptuel
ISO 19107:2003, Information géographique — Schéma spatial
ISO 19108:2002, Information géographique — Schéma temporel
ISO 19109:2005, Information géographique — Règles de schéma d'application
ISO 19111:2003, Information géographique — Système de références spatiales par coordonnées
ISO 19115:2003, Information géographique — Métadonnées
4 Termes, définitions, termes abrégés et notation
4.1 Termes et définitions
Pour les besoins du présent document, les termes et définitions suivants s’appliquent.
4.1.1
couverture continue
couverture qui assigne diverses valeurs au même attribut d’une entité en des positions directes différentes
dans un objet spatial, un objet temporel ou bien un objet spatio-temporel unique, selon le domaine
NOTE Bien que le domaine d’une couverture continue se limite, en règle générale, à son étendue spatiale et/ou
temporelle, il peut être subdivisé en un nombre infini de positions directes.
4.1.2
enveloppe convexe
le plus petit ensemble convexe contenant un objet géométrique donné
[2]
NOTE Adapté du Dictionary of Computing:1996 .
2 © ISO 2005 – Tous droits réservés
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ISO 19123:2005(F)
4.1.3
ensemble convexe
ensemble géométrique dans lequel toute position directe sur un segment de droite joignant deux
positions directes quelconques de l'ensemble géométrique est également contenue dans cet ensemble
géométrique
[2]
[Dictionary of Computing:1996 ]
4.1.4
coordonnée
une des séquences de n nombres désignant la position d’un point dans un espace à n dimensions
[ISO 19111:2003]
4.1.5
dimension de coordonnées
nombre de mesures ou d’axes nécessaire pour décrire une position dans un système de coordonnées
[ISO 19107:2003]
4.1.6
système de référence par coordonnées
système de coordonnées relié au monde réel par une donnée
[ISO 19111:2003]
4.1.7
couverture
entité qui agit comme une fonction en assignant des valeurs à partir de sa plage à toute position directe
dans son domaine spatial, temporel ou spatio-temporel
EXEMPLE Image matricielle, couverture de polygones, modèle numérique d’altitude.
NOTE En d’autres termes, une couverture est une entité qui prend des valeurs multiples selon le type d’attribut, où, à
chaque position directe dans la représentation géométrique de la caractéristique, chaque attribut correspond une valeur
unique.
4.1.8
géométrie de la couverture
configuration du domaine d’une couverture décrite à partir de coordonnées
4.1.9
courbe
primitive géométrique à une dimension, représentant l’image continue d’une ligne
[ISO 19107:2003]
NOTE La frontière d’une courbe correspond à l’ensemble de points à chaque extrémité de cette courbe.
4.1.10
triangulation de Delaunay
réseau de triangles, tel que le cercle passant par les sommets d’un triangle quelconque, ne circonscrit le
sommet d’aucun autre triangle
4.1.11
position directe
position décrite par un ensemble unique de coordonnées dans un système de référence par coordonnées
[ISO 19107:2003]
© ISO 2005 – Tous droits réservés 3
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ISO 19123:2005(F)
4.1.12
couverture discrète
couverture qui assigne les mêmes valeurs d’attribut à chaque position directe à l’intérieur d’un objet
spatial, temporel ou bien spatio-temporel unique dans son domaine
NOTE Le domaine d'une couverture discrète se compose d'un ensemble fini d'objets spatiaux, temporels ou
spatio-temporels.
4.1.13
domaine
ensemble bien défini
[ISO/TS 19103:2005]
NOTE Les domaines permettent de définir le domaine et l’étendue des opérateurs et des fonctions.
4.1.14
évaluation
〈couverture〉 détermination des valeurs d’une couverture en une position directe à l’intérieur du domaine de
la couverture
4.1.15
entité
0 abstraction de phénomènes du monde réel
[ISO 19101:2002]
4.1.16
attribut d’une entité
propriété d’une entité
[ISO 19101:2002]
4.1.17
fonction
règle qui associe chaque élément d’un domaine (source ou domaine de la fonction) à un élément unique d’un
autre domaine (cible, codomaine ou plage)
[ISO 19107:2003]
4.1.18
objet géométrique
objet spatial représentant un ensemble géométrique
[ISO 19107:2003]
4.1.19
primitive géométrique
objet géométrique représentant un élément de l'espace, défini comme unique, connexe et homogène
[ISO 19107:2003]
4.1.20
ensemble géométrique
ensemble de positions directes
[ISO 19107:2003]
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ISO 19123:2005(F)
4.1.21
objet à valeurs géométriques
objet composé d’un ensemble de paires à valeurs géométriques
4.1.22
paire à valeurs géométriques
paire ordonnée composée d’un objet spatial, d’un objet temporel ou d’un objet spatio-temporel ainsi que
d’un enregistrement des valeurs relatives à l’attribut de l’entité
4.1.23
grille
réseau composé de deux ensembles de courbes (ou plus) dans lequel les composants de chaque ensemble
coupent les composants des autres ensembles de manière algorithmique
NOTE Les courbes fractionnent un espace en cellules.
4.1.24
point de la grille
point situé à l’intersection d'au moins deux courbes dans une grille
4.1.25
évaluation inverse
〈couverture〉 sélection d’un ensemble d’objets provenant du domaine d’une couverture fondé sur les valeurs
de l’attribut de l’entité associées aux objets
4.1.26
point
primitive géométrique zéro-dimensionnelle, représentant une position
[ISO 19107:2003]
NOTE La frontière d’un point correspond à un ensemble vide.
4.1.27
couverture de points
couverture dont le domaine se compose de points
4.1.28
couverture de polygones
couverture dont le domaine se compose de polygones
4.1.29
plage
〈couverture〉 ensemble de valeurs attributaires d’une entité associé par u
...
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.Geografske informacije – Shema za geometrijo podatkovnega sloja in funkcijeInformation géographique -- Schéma de la géométrie et des fonctions de couvertureGeographic information -- Schema for coverage geometry and functions35.240.70Uporabniške rešitve IT v znanostiIT applications in scienceICS:Ta slovenski standard je istoveten z:ISO 19123:2005oSIST ISO 19123:2006en01-oktober-2006oSIST ISO 19123:2006SLOVENSKI
STANDARD
oSIST ISO 19123:2006
Reference numberISO 19123:2005(E)© ISO 2005
INTERNATIONAL STANDARD ISO19123First edition2005-08-15Geographic information — Schema for coverage geometry and functions Information géographique — Schéma de la géométrie et des fonctions de couverture
oSIST ISO 19123:2006
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oSIST ISO 19123:2006
ISO 19123:2005(E) © ISO 2005 – All rights reserved iiiContents Page Foreword.v Introduction.vi 1 Scope.1 2 Conformance.1 3 Normative references.2 4 Terms, definitions, abbreviated terms and notation.2 4.1 Terms and definitions.2 4.2 Abbreviated terms.7 4.3 Notation.7 5 Fundamental characteristics of coverages.8 5.1 The context for coverages.8 5.2 The coverage schema.9 5.3 CV_Coverage.10 5.4 CV_DomainObject.13 5.5 CV_AttributeValues.13 5.6 CV_CommonPointRule.14 5.7 CV_DiscreteCoverage.14 5.8 CV_GeometryValuePair.15 5.9 CV_ContinuousCoverage.16 5.10 CV_ValueObject.17 5.11 CV_InterpolationMethod.18 5.12 Subclasses of CV_ContinuousCoverage.18 6 Discrete coverages.18 6.1 Discrete coverage types.18 6.2 CV_DiscretePointCoverage.19 6.3 CV_PointValuePair.20 6.4 CV_DiscreteGridPointCoverage.20 6.5 CV_GridPointValuePair.21 6.6 CV_DiscreteCurveCoverage.21 6.7 CV_CurveValuePair.22 6.8 CV_DiscreteSurfaceCoverage.22 6.9 CV_SurfaceValuePair.24 6.10 CV_DiscreteSolidCoverage.24 6.11 CV_SolidValuePair.24 7 Thiessen polygon coverage.25 7.1 Thiessen polygon networks.25 7.2 CV_ThiessenPolygonCoverage.25 7.3 CV_ThiessenValuePolygon.27 8 Quadrilateral grid coverages.27 8.1 General.27 8.2 Quadrilateral grid geometry.27 8.3 CV_Grid.30 8.4 CV_GridEnvelope.31 8.5 CV_GridPoint.31 8.6 CV_GridCoordinate.32 8.7 CV_GridCell.32 8.8 CV_Footprint.33 8.9 CV_RectifiedGrid.33 oSIST ISO 19123:2006
ISO 19123:2005(E) iv © ISO 2005 – All rights reserved 8.10 CV_ReferenceableGrid.34 8.11 CV_ContinousQuadrilateralGridCoverage.35 8.12 CV_GridValueCell.36 8.13 CV_GridPointValuePair.36 8.14 CV_GridValuesMatrix.37 8.15 CV_SequenceRule.38 8.16 CV_SequenceType.38 9 Hexagonal Grid Coverages.39 9.1 General.39 9.2 CV_HexagonalGridCoverage.39 9.3 CV_GridValuesMatrix.41 9.4 CV_ValueHexagon.41 10 Triangulated irregular network (TIN) coverages.41 10.1 General.41 10.2 CV_TINCoverage.43 10.3 CV_ValueTriangle.43 11 Segmented curve coverages.44 11.1 General.44 11.2 CV_SegmentedCurveCoverage.45 11.3 CV_ValueCurve.45 11.4 CV_ValueSegment.46 11.5 Evaluation.46 Annex A (normative)
Abstract test suite.47 Annex B (informative)
UML Notation.51 Annex C (informative)
Interpolation methods.56 Annex D (informative)
Sequential enumeration.60 Bibliography.65
oSIST ISO 19123:2006
ISO 19123:2005(E) © ISO 2005 – All rights reserved vForeword 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 19123 was prepared by Technical Committee ISO/TC 211, Geographic information/Geomatics. oSIST ISO 19123:2006
ISO 19123:2005(E) vi © ISO 2005 – All rights reserved Introduction Geographic phenomena fall into two broad categories — discrete and continuous. Discrete phenomena are recognizable objects that have relatively well-defined boundaries or spatial extent. Examples include buildings, streams and measurement stations. Continuous phenomena vary over space and have no specific extent. Examples include temperature, soil composition and elevation. A value or description of a continuous phenomenon is only meaningful at a particular position in space (and possibly time). Temperature, for example, takes on specific values only at defined locations, whether measured or interpolated from other locations. These concepts are not mutually exclusive. In fact, many components of the landscape may be viewed alternatively as discrete or continuous. For example, a stream is a discrete entity, but its flow rate and water quality index vary from one position to another. Similarly, a highway can be thought of as a feature or as a collection of observations measuring accidents or traffic flow, and an agricultural field is both a spatial object and a set of measurements of crop yield through time. Historically, geographic information has been treated in terms of two fundamental types called vector data and raster data. “Vector data” deals with discrete phenomena, each of which is conceived of as a feature. The spatial characteristics of a discrete real-world phenomenon are represented by a set of one or more geometric primitives (points, curves, surfaces or solids). Other characteristics of the phenomenon are recorded as feature attributes. Usually, a single feature is associated with a single set of attribute values. ISO 19107:2003 provides a schema for describing features in terms of geometric and topological primitives. “Raster data”, on the other hand, deals with real-world phenomena that vary continuously over space. It contains a set of values, each associated with one of the elements in a regular array of points or cells. It is usually associated with a method for interpolating values at spatial positions between the points or within the cells. Since this data structure is not the only one that can be used to represent phenomena that vary continuously over space, this International Standard uses the term “coverage,” adopted from the Abstract Specification of the Open GIS Consortium [1], to refer to any data representation that assigns values directly to spatial position. A coverage is a function from a spatial, temporal or spatiotemporal domain to an attribute range. A coverage associates a position within its domain to a record of values of defined data types. In this International Standard, coverage is a subtype of feature. A coverage is a feature that has multiple values for each attribute type, where each direct position within the geometric representation of the feature has a single value for each attribute type. Just as the concepts of discrete and continuous phenomena are not mutually exclusive, their representations as discrete features or coverages are not mutually exclusive. The same phenomenon may be represented as either a discrete feature or a coverage. A city may be viewed as a discrete feature that returns a single value for each attribute, such as its name, area and total population. The city feature may also be represented as a coverage that returns values such as population density, land value or air quality index for each position in the city. A coverage, moreover, can be derived from a collection of discrete features with common attributes, the values of the coverage at each position being the values of the attributes of the feature located at that position. Conversely, a collection of discrete features can be derived from a coverage, each discrete feature being composed of a set of positions associated with specified attribute values.
oSIST ISO 19123:2006
INTERNATIONAL STANDARD ISO 19123:2005(E) © ISO 2005 – All rights reserved 1Geographic information — Schema for coverage geometry and functions 1 Scope This International Standard defines a conceptual schema for the spatial characteristics of coverages. Coverages support mapping from a spatial, temporal or spatiotemporal domain to feature attribute values where feature attribute types are common to all geographic positions within the domain. A coverage domain consists of a collection of direct positions in a coordinate space that may be defined in terms of up to three spatial dimensions as well as a temporal dimension. Examples of coverages include rasters, triangulated irregular networks, point coverages and polygon coverages. Coverages are the prevailing data structures in a number of application areas, such as remote sensing, meteorology and mapping of bathymetry, elevation, soil and vegetation. This International Standard defines the relationship between the domain of a coverage and an associated attribute range. The characteristics of the spatial domain are defined whereas the characteristics of the attribute range are not part of this standard. 2 Conformance This International Standard specifies interfaces for several types of coverage objects. In addition, it supports the interchange of coverage data independently of those interfaces. Thus, it specifies two sets of conformance classes: one for implementation of the interfaces, the other for the exchange of coverage data. Each set includes one conformance class for each type of coverage specified in this International Standard (Table 1). Table 1 — Conformance classes Conformance class Subclause Simple coverage interface A.1.1 Discrete coverage interface A.1.2 Thiessen polygon coverage interface A.1.3 Quadrilateral grid coverage interface A.1.4 Hexagonal grid coverage interface A.1.5 TIN coverage interface A.1.6 Segmented curve coverage interface A.1.7 Discrete coverage interchange A.2.1 Thiessen polygon coverage interchange A.2.2 Quadrilateral grid coverage interchange A.2.3 Hexagonal grid coverage interchange A.2.4 TIN coverage interchange A.2.5 Segmented curve coverage interchange A.2.6 oSIST ISO 19123:2006
ISO 19123:2005(E) 2 © ISO 2005 – All rights reserved In general, the interface conformance classes require implementation of all attributes, associations and operations of relevant classes. This set includes a single conformance class (A.2.1) that supports a simple interface for evaluation of any coverage type, but exposes none of the internal structure of the coverage. The remainder of the set are conformance classes that support interfaces to specific coverage types that expose additional information about the internal structure of the coverage. The interchange conformance classes require only implementation of the attributes and associations of the relevant classes. The Abstract Test Suite in Annex A shows the implementation requirements necessary to conform to this International Standard. Table 1 lists the subclauses of the Abstract Test Suite that apply for each conformance class. 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/TS 19103:2005, Geographic information — Conceptual schema language ISO 19107:2003, Geographic information — Spatial schema ISO 19108:2002, Geographic information — Temporal schema ISO 19109:2005, Geographic information — Rules for application schema ISO 19111:2003, Geographic information — Spatial referencing by coordinates ISO 19115:2003, Geographic information — Metadata 4 Terms, definitions, abbreviated terms and notation 4.1 Terms and definitions For the purposes of this document, the following terms and definitions apply. 4.1.1 continuous coverage coverage that returns different values for the same feature attribute at different direct positions within a single spatial object, temporal object or spatiotemporal object in its domain NOTE Although the domain of a continuous coverage is ordinarily bounded in terms of its spatial and/or temporal extent, it can be subdivided into an infinite number of direct positions. 4.1.2 convex hull smallest convex set containing a given geometric object [adapted from Dictionary of Computing:1996 [2]] 4.1.3 convex set geometric set in which any direct position on the straight-line segment joining any two direct positions in the geometric set is also contained in the geometric set [Dictionary of Computing:1996 [2]] oSIST ISO 19123:2006
ISO 19123:2005(E) © ISO 2005 – All rights reserved 34.1.4 coordinate one of a sequence of n numbers designating the position of a point in n-dimensional space [ISO 19111:2003] 4.1.5 coordinate dimension number of measurements or axes needed to describe a position in a coordinate system [ISO 19107:2003] 4.1.6 coordinate reference system coordinate system that is related to the real world by a datum [ISO 19111:2003] 41.7 coverage feature that acts as a function to return values from its range for any direct position within its spatial, temporal or spatiotemporal domain EXAMPLE Examples include a raster image, polygon overlay or digital elevation matrix. NOTE In other words, a coverage is a feature that has multiple values for each attribute type, where each direct position within the geometric representation of the feature has a single value for each attribute type. 4.1.8 coverage geometry configuration of the domain of a coverage described in terms of coordinates 4.1.9 curve 1-dimensional geometric primitive, representing the continuous image of a line [ISO 19107:2003] NOTE The boundary of a curve is the set of points at either end of the curve. 4.1.10 Delaunay triangulation network of triangles such that the circle passing through the vertices of any triangle does not contain, in its interior, the vertex of any other triangle 4.1.11 direct position position described by a single set of coordinates within a coordinate reference system [ISO 19107:2003] 4.1.12 discrete coverage coverage that returns the same feature attribute values for every direct position within any single spatial object, temporal object or spatiotemporal object in its domain NOTE The domain of a discrete coverage consists of a finite set of spatial, temporal, or spatiotemporal objects. oSIST ISO 19123:2006
ISO 19123:2005(E) 4 © ISO 2005 – All rights reserved 4.1.13 domain well-defined set [ISO/TS 19103] NOTE Domains are used to define the domain and range of operators and functions. 4.1.14 evaluation 〈coverage〉 determination of the values of a coverage at a direct position within the domain of the coverage 4.1.15 feature 0 abstraction of real world phenomena [ISO 19101] 4.1.16 feature attribute characteristic of a feature [ISO 19101] 4.1.17 function rule that associates each element from a domain (source or domain of the function) to a unique element in another domain (target, co-domain or range) [ISO 19107:2003] 4.1.18 geometric object spatial object representing a geometric set [ISO 19107:2003] 4.1.19 geometric primitive geometric object representing a single, connected, homogeneous element of space [ISO 19107:2003] 4.1.20 geometric set set of direct positions [ISO 19107:2003] 4.1.21 geometry value object object composed of a set of geometry value pairs 4.1.22 geometry value pair ordered pair composed of a spatial object, a temporal object or a spatiotemporal object and a record of feature attribute values oSIST ISO 19123:2006
ISO 19123:2005(E) © ISO 2005 – All rights reserved 54.1.23 grid network composed of two or more sets of curves in which the members of each set intersect the members of the other sets in an algorithmic way NOTE The curves partition a space into grid cells. 4.1.24 grid point point located at the intersection of two or more curves in a grid 4.1.25 inverse evaluation 〈coverage〉 selection of a set of objects from the domain of a coverage based on the feature attribute values associated with the objects 4.1.26 point 0-dimensional geometric primitive, representing a position [ISO 19107:2003] NOTE The boundary of a point is the empty set. 4.1.27 point coverage coverage that has a domain composed of points 4.1.28 polygon coverage coverage that has a domain composed of polygons 4.1.29 range 〈coverage〉 set of feature attribute values associated by a function with the elements of the domain of a coverage 4.1.30 raster usually rectangular pattern of parallel scanning lines forming or corresponding to the display on a cathode ray tube NOTE A raster is a type of grid. 4.1.31 record finite, named collection of related items (objects or values) [ISO 19107:2003] NOTE Logically, a record is a set of pairs . 4.1.32 rectified grid grid for which there is an affine transformation between the grid coordinates and the coordinates of an external coordinate reference system NOTE If the coordinate reference system is related to the earth by a datum, the grid is a georectified grid. oSIST ISO 19123:2006
ISO 19123:2005(E) 6 © ISO 2005 – All rights reserved 4.1.33 referenceable grid grid associated with a transformation that can be used to convert grid coordinate values to values of coordinates referenced to an external coordinate reference system NOTE If the coordinate reference system is related to the earth by a datum, the grid is a georeferenceable grid. 4.1.34 solid 3-dimensional geometric primitive, representing the continuous image of a region of Euclidean 3-space [ISO 19107:2003] NOTE A solid is realizable locally as a three-parameter set of direct positions. The boundary of a solid is the set of oriented, closed surfaces that comprise the limits of the solid. 4.1.35 spatial object object used for representing a spatial characteristic of a feature [ISO 19107:2003] 4.1.36 spatiotemporal domain 〈coverage〉 domain composed of spatiotemporal objects NOTE The spatiotemporal domain of a continuous coverage consists of a set of direct positions defined in relation to a collection of spatiotemporal objects. 4.1.37 spatiotemporal object object representing a set of direct positions in space and time 4.1.38 surface 2-dimensional geometric primitive, locally representing a continuous image of a region of a plane [ISO 19107:2003] NOTE The boundary of a surface is the set of oriented, closed curves that delineate the limits of the surface. 4.1.39 tessellation partitioning of a space into a set of conterminous subspaces having the same dimension as the space being partitioned NOTE A tessellation composed of congruent regular polygons or polyhedra is a regular tessellation. One composed of regular, but non-congruent polygons or polyhedra is a semi-regular tessellation. Otherwise, the tessellation is irregular. EXAMPLES Graphic examples of tessellations may be found in Figures 11, 13, 20 and 22 of this International Standard. 4.1.40 Thiessen polygon polygon that encloses one of a set of points on a plane so as to include all direct posi
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