Difference between revisions of "Modeling Guide for 3D Objects - Part 2: Modeling of Buildings (LoD1, LoD2, LoD3)"
Line 2,805: | Line 2,805: | ||
===== Definition ===== | ===== Definition ===== | ||
− | '''SIG3D:''' | + | '''SIG3D:''' |
+ | '''SIG3D:''' A '''dormer'''' is a structural element of a building that protrudes from the plane of a sloping roof surface. Dormers are used, either in original construction or as later additions, to create usable space in the roof of a building by adding headroom and usually also by enabling addition of windows [Wikipedia]. | ||
− | + | A '''dormer''' does not lie on the same plane as the building's exterior wall. The dormer (or the dormer's footprint) has a minimum offset of 0,5 m and lies inside the building's footprint. | |
− | '''SIG3D:''' | + | '''SIG3D:''' The '''Zwerchhaus''' is a one or more story installation of a sloping roof surface. It consists of a gable and its own roof. The !!!Zwerchgiebel!!! follows the exterior wall's building line. That represents the difference between a !!!Zwerchhaus!!! and a gable, because a gable does not have to follow the building line. The roof of the !!!Zwerchhaus!!! is often designed as a ridge roof. The ridge follows cross to the main roof's ridge. So the rainwater pipes continue in an orthogonal way to each other. |
− | ''' | + | '''Note:''' The '''zwerchhaus''' is not modeled as a part of the building installation, but as a building's boundary surface itself. |
===== CityGML Feature ===== | ===== CityGML Feature ===== | ||
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===== Geometry ===== | ===== Geometry ===== | ||
− | *'''''gml:Geometry'' <span style="color:#FF0000"> | + | *'''''gml:Geometry'' <span style="color:#FF0000">not recommended</span>''' |
− | *'''''bldg:boundedBy'' <span style="color:#00FF00"> | + | *'''''bldg:boundedBy'' <span style="color:#00FF00">recommended</span>''' |
− | ** | + | ** Threshold LOD2: |
− | *** | + | *** Modeling only, if the dormer's height >= 2 m; |
− | ** | + | ** Threshold LOD3: |
*** | *** | ||
− | ** ''' | + | ** '''Modeling Principle''' |
− | *** | + | *** The building contains all geometry-containing boundary surfaces of the building structure. To close the building's volume, a ClosureSurface is modeled into the roof's gap. |
− | *** | + | *** The dormer (BuildingInstallation) '''contains all geometry-containing boundary surfaces''' of the dormer. To close the volume, either a ClosureSurface is modeled or it is closed by referencing to the building's corresponding ClosureSurface (Xlink to OrientableSurface). |
− | *** | + | *** The building's volume, the building structure's volume and the volume of the dormer ('''CompositeSolid''') reference (Xlink)to the corresponding boundary surfaces of the building structure and dormer. |
<table border="0" cellspacing="6"> | <table border="0" cellspacing="6"> | ||
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<tr align="center" valign="top"> | <tr align="center" valign="top"> | ||
<td> | <td> | ||
− | + | Modelling Principle of a dormer</td> | |
</tr> | </tr> | ||
</table> | </table> | ||
Line 2,845: | Line 2,846: | ||
===== Attributes ===== | ===== Attributes ===== | ||
;''bldg:function'' | ;''bldg:function'' | ||
− | : | + | :Dormer (1003); see SIG 3D codelisten recommendation for[http://www.sig3d.org/codelists/Handbuch-SIG3D/building/2.0/CL-V1.0/BuildingInstallation_function.xml ''bldg:BuildingInstallation --> function'' ] |
;''bldg:boundedBy'' | ;''bldg:boundedBy'' | ||
− | :<span style="color:#00FF00">''' | + | :<span style="color:#00FF00">'''recommended:'''</span> A dormer is considered as a building component which semantically consists of the building's boundary surfaces. |
===== Examples ===== | ===== Examples ===== | ||
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<tr align="left"> | <tr align="left"> | ||
<td colspan="6"> | <td colspan="6"> | ||
− | ''' | + | '''Dormer''' |
</td> | </td> | ||
</tr> | </tr> | ||
Line 2,860: | Line 2,861: | ||
<tr align="middle" valign="top"> | <tr align="middle" valign="top"> | ||
<td> | <td> | ||
− | + | Actual Example | |
</td> | </td> | ||
<!-- <td> | <!-- <td> | ||
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<td width="200px" valign="top"> | <td width="200px" valign="top"> | ||
[[image:DachgaubeClosure-01-LOD2.jpg|200px]] | [[image:DachgaubeClosure-01-LOD2.jpg|200px]] | ||
− | [http://quality.citygmlwiki.org/images/b/b5/DachgaubeClosure-V1.gml CityGML | + | [http://quality.citygmlwiki.org/images/b/b5/DachgaubeClosure-V1.gml CityGML download] |
</td> | </td> | ||
<td width="200px" valign="top"> | <td width="200px" valign="top"> | ||
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<tr align="middle" valign="top"> | <tr align="middle" valign="top"> | ||
<td> | <td> | ||
− | + | Actual Example | |
</td> | </td> | ||
<!-- <td> | <!-- <td> | ||
Line 2,941: | Line 2,942: | ||
<td width="200px" valign="top"> | <td width="200px" valign="top"> | ||
[[image:Zwerchgiebel-LOD0-v02.png|170px]] | [[image:Zwerchgiebel-LOD0-v02.png|170px]] | ||
− | [http://quality.citygmlwiki.org/images/a/a0/Zwerchgiebel-LOD0-V01.gml CityGML | + | [http://quality.citygmlwiki.org/images/a/a0/Zwerchgiebel-LOD0-V01.gml CityGML download] |
</td> | </td> | ||
<td width="200px" valign="top"> | <td width="200px" valign="top"> | ||
[[image:Zwerchgiebel-LOD1-v02.png|170px]] | [[image:Zwerchgiebel-LOD1-v02.png|170px]] | ||
− | [http://quality.citygmlwiki.org/images/3/32/Zwerchgiebel-LOD1-V01.gml CityGML | + | [http://quality.citygmlwiki.org/images/3/32/Zwerchgiebel-LOD1-V01.gml CityGML download] |
</td> | </td> | ||
<td width="200px" valign="top"> | <td width="200px" valign="top"> | ||
[[image:Zwerchgiebel-LOD2-v02.png|170px]] | [[image:Zwerchgiebel-LOD2-v02.png|170px]] | ||
− | [http://quality.citygmlwiki.org/images/4/4b/Zwerchgiebel-LOD2-V02.gml CityGML | + | [http://quality.citygmlwiki.org/images/4/4b/Zwerchgiebel-LOD2-V02.gml CityGML download] |
</td> | </td> | ||
<td width="200px" valign="top"> | <td width="200px" valign="top"> | ||
[[image:Zwerchgiebel-LOD3-v02.png|170px]] | [[image:Zwerchgiebel-LOD3-v02.png|170px]] | ||
− | [http://quality.citygmlwiki.org/images/d/d4/Zwerchgiebel-LOD3-V01.gml CityGML | + | [http://quality.citygmlwiki.org/images/d/d4/Zwerchgiebel-LOD3-V01.gml CityGML download] |
</td> | </td> | ||
Revision as of 14:02, 5 December 2013
Document History
Version |
Datum |
Autor/en |
Status |
Bemerkungen |
---|---|---|---|---|
0.8.0 |
Januar 2012 |
nicht öffentlich |
Erste Versuche |
|
0.9.0 |
April 2012 |
nicht öffentlich |
Fertigstellung von Kapitel 1-4.1; 4.2 wird später bearbeitet |
|
1.0.0 |
Mai 2012 |
SIG 3D / AG Qualität |
öffentlich |
Erste öffentliche Version von Kapitel 1-4.1; |
1.1.0 |
Januar/Februar 2013 |
SIG 3D / AG Qualität |
nicht öffentlich |
Vorbereitung Version 2.0.0 mit Erweiterter Modellierung; |
2.0.0 |
März 2013 |
SIG 3D / AG Qualität (c) 2013 Copyright Special Interest Group 3D (SIG3D) of the Spatial Data Infrastructure Germany (GDI-DE) http://www.sig3d.org |
öffentlich |
Erste öffentliche Version mit Erweiterter Modellierung; |
2.0.0 EN |
November 2013 |
SIG 3D / Quality Working Group (c) 2013 Copyright Special Interest Group 3D (SIG3D) of the Spatial Data Infrastructure Germany (GDI-DE) http://www.sig3d.org /EC, KHH |
public |
First English version; |
Introduction
Scope
- The modeling recommendations are usually independent from the recording method, that means that this document is not a recording manual.
- This document describes the modeling of 3D objects on the basis of existing information. In case of lacking information, in particular in case of missing height information, objects must explicitly not be modeled. For example, if all relevant information on balconies are available, this document provides recommendations for a standardized modeling. Otherwise balconies must not be modeled.
- Recommendations are related to the Open Geospatial Consortium (OGC) standard CityGML version 1.0 and 2.0.
- This document refers to national (German) and European standards (AdV, INSPIRE) and can only be partially generalized.
- This document is restricted to the outer shell of buildings, i.e. building modeling up to LoD3
Target Group
- Modeler
- Data holder
- Developer
Prior Knowledge Required
- GML: Geography Markup Language
- CityGML: Application schema for GML for the representation, storage, and exchange of virtual 3D city and landscape models
- ALKIS: Official German Land Registry Information System
Further References
Document Conventions
- Features are written in italic characters with the corresponding name space in bold characters .
- Examples are written in fixed width.
- Online references to other internal or external pages and documents are written in blue.
- A statement which is not valid for all Levels of Detail (LoD) is noted as (LoD[1234][+]), e.g. a notation with (LoD1) is only valid for LoD1, a notation (LoD2+) is valid for all LoDs from LoD2 and above.
Definitions und Determinations
Level of Detail (Building, BuildingPart)
Definitions of SIG 3D:
- LoD0
- For every building or building part the footprint or roof outline is representad by a horizontal polygon with a well defined absolute and constant height.
- LoD1
- For every building or building part the generalized outer shell is represented by exactly one prismatic extrusion solid. Ground, floor and roof surfaces must be horizontal, lateral boundary surfaces must be vertical.
- LoD2
- For every building or building part the geometrically simplified outer shell is represented by horizontal resp. vertical outer surfaces and simplified roof shapes. All kind of surfaces ( e.g. ground surfaces, wall surfaces, roof surfaces, outer ceiling surfaces, outer floor surfaces, virtual closure surfaces ) and additional building elements ( e.g. building installations like balkonies, dormers and chimneys ) may be represented as semantic objects.
- LoD3
- For every building or building part the geometrically detailed outer shell is represented by detailed outer surfaces and detailed roof shapes. All kind of surfaces ( e.g. ground surfaces, wall surfaces, roof surfaces, outer ceiling surfaces, outer floor surfaces, virtual closure surfaces ) and additional building elements ( e.g. building installations like balkonies, dormers and chimneys ) may be more detailly represented as semantic objects. In respect to LoD2 doors and windows can be modeled as planar thematic objects.
- LoD4
- For every building or building part the geometrically detailed outer shell and interior is represented by detailed outer and inner surfaces and detailed roof shapes. All kind of surfaces ( e.g. ground surfaces, inner and outer wall surfaces, inner and outer roof surfaces, outer ceiling surfaces, outer floor surfaces, virtual closure surfaces ) and additional movable and non movable building elements ( e.g. building installations like balkonies, dormers, chimneys, interior and furniture ) may be more detailly represented as semantic objects.
Reference Coordinate System
CityGML 2.0 strongly recommends the specification of a reference coordinate system. For a meaningful use of data a valid reference coordinate system is imperative, therefore a valid reference coordinate system must be defined for each instance file:
- A reference coordinate system must be defined as three dimensional (usually position and height reference system --> see Compound Coordinate Reference System).
- A reference coordinate system should not be changed within an instance file.
- A reference coordinate system should be defined once within <gml:Envelope>.
Recommendations for Germany: ETRS89 / UTM / Reference ellipsoid GRS80 + DHHN92
CityGML Example:
<gml:boundedBy> <gml:Envelope srsDimension="3" srsName="urn:adv:crs:ETRS89_UTM32*DE_DHHN92_NH"> --> see Compound Coordinate Reference System <gml:lowerCorner srsDimension="3">458868.0 5438343.0 112.0 </gml:lowerCorner> <gml:upperCorner srsDimension="3">458892.0 5438362.0 117.0 </gml:upperCorner> </gml:Envelope> </gml:boundedBy>
ALKIS Example:
<gml:boundedBy> <gml:Envelope srsName="urn:adv:crs:ETRS89_UTM32"> <gml:pos>367456.554 5718128.391</gml:pos> <gml:pos>367505.094 5718091.143</gml:pos> </gml:Envelope> </gml:boundedBy>
see also Modeling Guide for 3D Objects - Part 1
Model Structure
The use of core:CityModel is not explicitely regulated in the specification and in the schema. The multiple use of core:CityModel is compliant to the schema and will be validated. In order to avoid conflicts while importing CityGML models, it is recommended to use exactly one instance of core:CityModel as root element.
Heights
The measuredHeight is the measured or computed difference between the lowest terrain intersection point and the highest roof point with the following properties:
- the measuredHeight is a simple attribute can not further specified and/or qualified;
- the measuredHeight is always related to the real building;
- the measuredHeight is independent of the LoD of the building;
- the computation of the measuredHeight should always base on the terrain model with the highest available resolution.
The following heights are valid for flat roofs, outshot roofs, gable roofs, hip roofs, jerkinhead roofs, mansard roofs, pyramid roof, shed roof, shells and domes:
The following heights are valid for all kind of shed roofs:
The following heights are valid for different roof overhangs:
If you need absolute heights for the noted values you must define them as generic attributes (dimensioned gen:measureAttribute):
- <gen:measureAttribute name="min height surface"><gen:value uom="#m">Value</gen:value></gen:measureAttribute>
- <gen:measureAttribute name="min height eaves"><gen:value uom="#m">Value</gen:value></gen:measureAttribute>
- <gen:measureAttribute name="max height eaves"><gen:value uom="#m">Value</gen:value></gen:measureAttribute>
- <gen:measureAttribute name="max height ridge"><gen:value uom="#m">Value</gen:value></gen:measureAttribute>
Terrain Intersection Line
In CityGML the terrain intersection line is an attribute of a building or building part. It is generated by intersection of the building or building part with the terrain and has the following properties:
- a terrain intersection line can be measured or calculated ;
- if a terrain intersection line is calculated, the terrain model with the highest resolution available should be used;
- a terrain intersection line is an attribute of the building or building part;
- outer building installations (bldg:BuildingInstallation) are taken into account from a terrain intersection line (see Figure A);
- a terrain intersection line is a result of the intersection of buildings in the respective LoD and the most accurate available terrain. In CityGML it has no relation to the terrain used in a visualization and its resolution and accuracy.
- a terrain intersection line may consist of several independent parts;
- a terrain intersection line need not be closed;
- a terrain intersection line which does not exist in reality will not be taken into account (e.g. in the case of building parts ).
Figure A |
Figure B |
Figure C |
Figure D |
Cantilevered Building Elements
Cantilevered or projecting building elements are defined as parts of roofs, walls etc, which should not be considered in the volume calculation of the building. Cantilevered or projecting building elements are modeled as follows:
- as surface element(s) always separated from the volume-forming building element (see Figure A)
- always as a surface element, if the thickness of the building element is less than 0.5 m (see Figure B)
- always as a solid element, if the thickness of the building element is greater than 0.5 m (see Figure B)
- in LoD2 always as a surface element, if the thickness of the building element is less than 0.5 m
- in LoD2 always as a solid element, if the thickness of the building element is greater than 0.5 m
- in LoD3 always in the best accuracy based on available information.
Figure A |
Figure B |
Closed Coverage Type
Buildings as parts of closed coverage type (applies to semi-detached and terrace houses also) can be modeled as follows:
- Buildings that are separated within the land register should be modeled as separate buildings.
Separate buildings of closed coverage type | Terrace houses as separate buildings |
- Buildings that are united within the land register should be modeled as one single building which can be subdivided into building parts (e.g. row of buildings, semi-detached or terrace houses).
Terrace houses as one single building | Terrace houses as building parts |
- Buildings without any land register information and for which the building detection provides no usable structures (e.g. based on flights) should be modeled as one single building.
Terrace houses as one single building
The modeling of boundary surfaces between buildings must satisfy the following geometric resp. semantic conditions:
- Common boundary surfaces may only be referenced within a building via Xlink (building-building part resp. building part - building part).
Addresses
- The CityGML specification allows to assign an address both to a building (bldg:Building, bldg:BuildingPart) as well to a door (bldg:Door). It is recommended always to assign an address to a building (in any LoD) because doors are not available in LoD1 and LoD2.
- It is recommended to use the complete postal address.
- Multiple addresses can be assigned to one building.
- Umlauts are allowed in addresses (z.B. Würzburg☺, Wuerzburg☺, Würzburg and Wuerzburg mixed ☹).
General example:
Street: Hermann-von-Helmholtz-Platz Number: 1 Zip Code: 76344 City: Eggenstein-Leopoldshafen
CityGML example:
<core:Address> <core:xalAddress> <xAL:AddressDetails> <xAL:Locality Type="Town"> <xAL:LocalityName>Eggenstein-Leopoldshafen</xAL:LocalityName> <xAL:Thoroughfare Type="Street"> <xAL:ThoroughfareNumber>1</xAL:ThoroughfareNumber> <xAL:ThoroughfareName>Hermann-von-Helmholtz-Platz</xAL:ThoroughfareName> </xAL:Thoroughfare> <xAL:PostalCode> <xAL:PostalCodeNumber>76344</xAL:PostalCodeNumber> </xAL:PostalCode> </xAL:Locality> </xAL:AddressDetails> </core:xalAddress> </core:Address>
Codelists
Codelists for the CityGML 2.0 standard are available at "http://www.sig3d.org/codelists/standard".
The recommendations for codelists in this modeling guide refer to the proposal of the SIG3D. These codelists are availabe (in German only) at "http://www.sig3d.org/codelists/Handbuch-SIG3D" and relate to ALKIS.
This modeling guide refers to the following codelists:
- Building resp. building part (bldg:Building / bldg:BuildingPart)
- class http://www.sig3d.org/codelists/Handbuch-SIG3D/building/2.0/CL-V1.0/_AbstractBuilding_class.xml
- function http://www.sig3d.org/codelists/Handbuch-SIG3D/building/2.0/CL-V1.0/_AbstractBuilding_function.xml
- usage http://www.sig3d.org/codelists/Handbuch-SIG3D/building/2.0/CL-V1.0/_AbstractBuilding_usage.xml
- roofType http://www.sig3d.org/codelists/Handbuch-SIG3D/building/2.0/CL-V1.0/_AbstractBuilding_roofType.xml
- Building installations (bldg:BuildingInstallation)
Generic Attributes
Generic (user defined) attributes may be used to represent attributes which are not covered explicitly by the CityGML schema. Generic attributes must be used with care; they shall only be used if there is no appropriate attribute available in the overall CityGML schema. Otherwise, problems concerning semantic interoperability may arise. Interoperability of generic attributes is reduced to attribute values which can only be interpreted semantically by additional information. The following attribute types are defined:
- stringAttribute - for arbitrary strings
- intAttribute - for dimensionless integer numbers
- doubleAttribute - for dimensionless floating point numbers
- dateAttribute - for dates with integer-valued year, month and day representation in the format YYYY-MM-DD (e.g. 2013-03-08)
- uriAttribute - represents a Uniform Resource Identifier Reference (URI) (e.g. a link to a document or a web site)
- measureAttribute - for dimensioned values (CityGML 2.0)
Attributes can be combined in CityGML 2.0 by generic attribute sets genericAttributeSet with an optional codeSpace. If the codeSpace attribute is present, then its value should identify an authority for the set, such as the organisation or community who defined its content. The generic attribute set may contain arbitrary generic attributes.
CityGML Examples
<gen:stringAttribute name="construction"><gen:value>concrete</gen:value></gen:stringAttribute> <gen:intAttribute name="entries"><gen:value>3</gen:value></gen:intAttribute> <gen:doubleAttribute name="floor area ratio FAR"><gen:value>0.33</gen:value></gen:doubleAttribute> <gen:dateAttribute name="approval date"><gen:value>2012-03-09</gen:value></gen:dateAttribute> <gen:uriAttribute name="website "><gen:value>http://www.sig3d.org</gen:value></gen:uriAttribute> <gen:measureAttribute name="building width"><gen:value uom="#m">10.00</gen:value>/gen:measureAttribute>
<gen:genericAttributeSet name="Base Quantities"> <gen:measureAttribute name="Height"><gen:value uom="#m">9.00</gen:value></gen:measureAttribute> <gen:measureAttribute name="Area"><gen:value uom="#m2">80.00</gen:value></gen:measureAttribute> <gen:measureAttribute name="Volume"><gen:value uom="#m3">720.00</gen:value></gen:measureAttribute> </gen:genericAttributeSet>
Geometry
There is no GML Profile for CityGML. This means that CityGML instance files will validate with every GML geometry. The specification restricts the usage of GML geometry classes (CityGML 2.0 Annex D "Overview of employed GML3 geometry classes). CityGML references to the following geometry classes (CityGML 2.0 Annex D):
Abstract Classes |
Instantiated Classes |
Further Limitations |
gml:_Solid |
gml:Solid |
only gml:OrientableSurface, gml:Polygon, gml:CompositeSurface, tex:TexturedSurface (obsolete) |
gml:CompositeSolid |
no restriction |
|
gml:_Surface |
gml:Polygon |
only gml:LinearRing and gml:Ring exclusively with gml:LineString or gml:CompositeCurve |
gml:OrientableSurface |
no restriction |
|
tex:TextureSurface |
obsolete |
|
gml:CompositeSurface |
only gml:OrientableSurface, gml:Polygon, gml:CompositeSurface tex:TexturedSurface (veraltet) |
|
gml:TriangulatedSurface |
no restriction |
|
gml:Tin |
no restriction |
|
gml:_Curve |
gml:LineString |
no restriction |
gml:CompositeCurve |
gml:LineString and gml:CompositeCurve only |
|
gml:_GeometricPrimitive |
gml:Point |
no restriction |
gml:_Coverage |
gml:RectifiedGridCoverage |
no restriction |
gml:_AbstractGeometricAggregate |
gml:MultiSolid |
no restriction |
gml:MultiSurface |
only gml:OrientableSurface, gml:Polygon, gml:CompositeSurface, tex:TexturedSurface (obsolete) |
|
gml:MultiCurve |
only gml:LineString and gml:CompositeCurve |
|
gml:MultiPoint |
no restriction |
|
gml:GeometricComplex |
restricted to connected linear networks |
|
gml:MultiGeometry |
restrictrions see allowed geometry types |
In order to keep the instance files small and to ensure an optimal editability of models, maximum flat polygons should be used, if appropriate with holes (inner rings).
File Name
It is recommended to use *.gml as file extension to distinguish CityGML files from other XML files.
Modeling
Base Modeling
The base modeling includes the modeling of the building resp. building part itself in LoD1, with appropriate boundary surfaces in LoD2 and LoD3 and with windows and doors in LoD3. In addition, the basic modeling covers the general use of building installations.
Building (bldg:Building)
Definition
SIG3D: A free-standing self-supporting construction that is roofed, usually walled, and can be entered by humans and is normally designed to stand permanently in one place. It is intended for human occupancy (for example: a place of work or recreation), habitation and/or shelter of humans, animals or things.
ISO: Provision of shelter for its occupants or contents as one of its main purposes; usually partially or totally enclosed and designed to stand permanently in one place
CityGML Feature
bldg:Building
Geometry
gml:Solid see Modeling Guide - Part 1
It is recommended to use gml:Solid depending on the LoD in the following way :
- In LoD1 a solid directly contains the bounding geometry (Figure A)
- In LoD2 and LoD3 a solid contains external references (Xlinks) to the bounding geometry (wall surfaces, roof surfaces, ground surfaces, outer ceiling surfaces, outer bottom surfaces and closure surfaces as well as doors and windows) (Figure B) ( see also conformance requirement no. 4 in chapter 10.3.9 of the CityGML V2.0 specification )
Figure A |
Figure B |
gml:MultiSurface (not recommended)
gml:MultiCurve (not recommended)
Attributes
- gml:id (mandatory)
- from GML version 3.2 onwards an id is mandatory
- gml:name (recommended, if available in the underlying land register)
- 'name' is the proper name or the name of the building.
- bldg:class (LoD1, LoD2, LoD3)
- The attribute bldg:class allows an unspecified classification of the building; no suggestion from the SIG3D;
- bldg:function (LoD1, LoD2, LoD3) (recommended)
- The 'function' of a building is the predominantly functional significance of the building at the date of data collection ( principle of dominance ); see also in the SIG3D code lists.
- bldg:usage (LoD1, LoD2, LoD3) (conditionally recommended)
- The 'usage' of a building describes the use of the building and contains the respective percentage usage share of the total use.
- bldg:yearOfConstruction (LoD1, LoD2, LoD3) (recommended)
- The 'yearOfConstruction' is the year of completion of the construction or alteration of the building;
- bldg:yearOfDemolition (LoD1, LoD2, LoD3)
- The 'yearOfDemolition' is the year of deconstruction of the building;
- bldg:roofType (LoD1, LoD2, LoD3) (recommended)
- 'Roof type' describes the characteristic shape of the roof; see also in the code list of the SIG3D
- bldg:measuredHeight (LoD1, LoD2, LoD3) (recommended)
- 'Measured height' is the difference in [m] between the highest point of the roof structure and the defined footprint of the building; see also Heights
- bldg:storeysAboveGround (LoD1, LoD2, LoD3) (recommended, if available in the underlying land register)
- 'storeys above ground' is the number of above-ground floors
- bldg:storeysBelowGround (LoD1, LoD2, LoD3) (recommended, if available in the underlying land register)
- 'storeys below ground' is the number of underground floors
- bldg:storeysHeightsAboveGround (LoD1, LoD2, LoD3)
- Height between two consecutive floors of the above-ground floors
- bldg:storeysHeightsBelowGround (LoD1, LoD2, LoD3)
- Height between two consecutive floors of the underground floors
- bldg:lodXSolid (LoD1, LoD2, LoD3)
- LoDX geometry (volume)of the building
- bldg:lodXMultiSurface (LoD1, LoD2, LoD3) (not recommended)
- LoDX geometry (surface) of the building
- bldg:lodYMultiCurve (LoD2, LoD3) (not recommended)
- LoDY geometry (curve) of the building
- bldg:lodXTerrainIntersection (LoD1, LoD2, LoD3)
- LoDX geometry (curve) of the terrain intersection line of the building
- bldg:outerBuildingInstallation (LoD2, LoD3)
- Relation to LoD2/LoD3 building installation
- bldg:boundedBy (LoD2, LoD3)
- Relation to boundary surfaces (wall surfaces, roof surfaces, ground surfaces, outer ceiling surfaces, outer floor surfaces and closure surfaces)
- bldg:consistsOfBuildingPart (LoD1, LoD2, LoD3)
- Relation to LoD1/LoD2/LoD3 building parts
- bldg:address (LoD1, LoD2, LoD3)
- Relation to one or more building addresses
Examples
Detached family house |
|||||
Real Building |
CityGML LOD0 |
CityGML LOD1 |
CityGML LOD2 |
CityGML LOD3 |
Building Part (bldg:BuildingPart)
Definition
SIG3D: A building part is a sub-division of a building that is homogeneous related to its physical, functional or temporal aspects and may be considered as a building.
The subdivision of a building can be done by different criteria, e.g.
- structural like number of floors, roof type, height, construction method,
- administrative like building function, ownership, year of construction.
Building parts (bldg:BuildingParts) must satisfy the following conditions ( necessary conditions ):
- A building part always has a relation (bldg:consistsOfBuildingPart) to exactly one building:
- Buildings and building parts touch each other planar or linear-shaped,
- Building parts must be "connected to ground" and can have the following properties ( for example, storeys are no building parts ):
- Building parts may have different building attributes ( e.g. function, roof type ),
- Building parts may have a address that differs from the address of the building,
- The geometry of building parts (bldg:BuildingParts) must be modeled in a way that both the volume and the surfaces of the boundary surfaces ( wall surfaces, roof surfaces and ground surfaces ) correspond to the real conditions (see chapter Building Part/Geometry),
- If a building part is emphasized as the main part of the building, its semantics and geometry can be modeled in the parent building,
- Building parts will not be subdivided into further building parts.
CityGML Feature
bldg:BuildingPart
Geometry
gml:Solid see also Modeling Guide for 3D Objects - Part 1
It is recommended to use gml:Solid depending on the LoD in the following way :
- In LoD1 a solid directly contains the bounding geometry (Figure A)
- In LoD2 and LoD3 a solid contains external references (Xlinks) to the bounding geometry (wall surfaces, roof surfaces, ground surfaces, outer ceiling surfaces, outer bottom surfaces and closure surfaces as well as doors and windows). In real nonexistent surfaces are modeled as closure surfaces (Figure B).
- In LoD2 a solid contains external references (Xlinks) to the real bounding geometry. In real nonexistent surfaces are modeled as closure surfaces and assigned directly to the building part (Figure C).
Figure A |
Figure B |
Figure C |
bldg:boundedBy Relation to boundary surfaces ( wall surfaces, roof surfaces, ground surfaces, outer ceiling surfaces, outer bottom surfaces and closure surfaces )
gml:MultiSurface (not recommended)
gml:MultiCurve (not recommended)
Attributes
Since the building part is derived from the building, all attributes of the building are also available for the building part (see also Building Attribute).
Exception: bldg:consistsOfBuildingPart
Examples
Office with factory hall |
|
"structurally distinct" building parts → "Office" as function of BuildingPart 1 ; "Factory Hall" as function of BuildingPart 2 |
Detached house with staggered shed roof |
House with a projecting floor |
No "structurally distinct" building parts → roofType "staggered shed roof" |
No "structurally distinct" building parts; 1 building part not "connected to ground" |
Examples with overarching building parts
Building Installations (bldg:BuildingInstallation)
Definition
SIG3D: Permanently installed parts of the buildings outer shell which are accessory for the building structure including loggia, dormer, etc. Doors and windows are modeled by the corresponding CityGML classes.
CityGML Feature
- LOD1: not available
- LOD2: bldg:BuildingInstallation
- LOD3: bldg:BuildingInstallation
Geometry
gml:Geometry
gml:Geometry erlaubt Punkte, Linien, Flächen, Volumen und jede Kombination der genannten Geometrie Elemente. Die Verwendung von Punkten wird nicht empfohlen. Die Verwendung von Linien wird nur bedingt empfohlen, da nicht alle Anwendungen diese Geometrie verarbeiten können.
Lines (e.g. Antenna) |
Sufaces (e.g. Solar Panel) |
Volumes (e.g. Chimney) |
Lines and Surfaces (e.g. Satellite Dish) |
Lines and Surfaces respectively Surfaces and Volumes (e.g. stair and porch) |
Lines, Surfaces und Volumes (e.g. Balcony) |
bldg:boundedBy Relation zu Begrenzungsflächen (Wand-, Dach-, Grund-, Äußere Decken-, Äußere Boden- und virtuelle Begrenzungsfläche) --> siehe auch Erweiterte Modellierung
Building with a small ridge turret (modeled as building installation with geometry) |
Building with a tower (modeled as building installation with boundary surfaces) |
Attributes
- gml:id (verpflichtend)
- mit der GML Version 3.2 wird eine id verpflichtend
- bldg:class (LOD2, LOD3) (not recommented)
- Keine Definition der SIG3D;
- bldg:function (LOD2, LOD3) (empfohlen)
- Art der Gebäudeinstallation zum Zeitpunkt der Erhebung; siehe Codeliste SIG 3D;
- bldg:usage (LOD2, LOD3) (not recommented)
- Keine Definition der SIG3D;
- bldg:lodXGeometry (LOD2, LOD3)
- LODX geometry of the building installation
Examples
LOD1 keine Gebäudeinstallation |
LOD2 generalisierte Gebäudeinstallation |
LOD3 detaillierte Gebäudeinstallation |
LOD1 keine Gebäudeinstallation |
LOD2 generalisierte Gebäudeinstallation |
LOD3 detaillierte Gebäudeinstallation |
Ground Surfaces (bldg:GroundSurface)
Definition
SIG3D: Exterior, lower boundary surface of a building , building part or building installation against soil or water.
CityGML Feature
- LOD1: not available
- LOD2: bldg:GroundSurface
- LOD3: bldg:GroundSurface
Geometry
gml:MultiSurface siehe auch Handbuch - Teil 1
- Eine Grundfläche besteht nur aus den von außen sichtbaren Flächen.
- Die Lage (Elevation) der Grundfläche wird durch die Datenverfügbarkeit bestimmt:
- Liegen Informationen über Kellergeschosse vor, so liegt die Grundfläche bei Unterkante Kellerboden (Figure A);
- Wird die untere Berandung des Gebäudes durch den Verschnitt mit dem Gelände erzeugt, so liegt die Grundfläche auf dem Niveau des niedrigsten absoluter Geländepunkts der Geländeschnittlinie (Figure B);
- Wird die Grundfläche aus dem Verschnitt mit dem Gelände erzeugt, liegt die Grundfläche auf dem Gelände (nicht empfohlen)(Figure C).
Figure A |
Figure B |
Figure C |
Attribute
- bldg:lod2MultiSurface
- Zeigt auf die LOD2 Flächengeometrie der Grundfläche
- bldg:lod3MultiSurface
- Zeigt auf die LOD3 Flächengeometrie der Grundfläche
- bldg:opening not recommented
- Zeigt auf ein CityGML feature bldg:Opening (bldg:Door (siehe Türen) oder bldg:Window (siehe Fenster))
Examples
Einfache Bodenplatte ohne Keller (1x bldg:GroundSurface) |
Einfache Bodenplatte im Keller (1x bldg:GroundSurface) |
Zwei getrennte Bodenflächen bei teilweise unterkellertem Gebäude (2x bldg:GroundSurface) |
Zwei Bodenflächen mit unterschiedlicher Orientierung bei Rampen (2x bldg:GroundSurface) |
Bodenfläche auf dem Niveau des Kellerbodens (1x bldg:GroundSurface) |
Bodenfläche auf dem Niveau des niedrigsten Punktes der Geländeschnittlinie (1x bldg:GroundSurface) |
Bodenfläche als Ergebnis mit dem Geländeverschnitt (1x bldg:GroundSurface) nicht empfohlen |
Wall Surfaces (bldg:WallSurface)
Definition
SIG3D: Exterior, lateral boundary surface of a building , building part or building installation.
Die Normalen der Wandflächen liegen in der Regel in der Horizontalen (+45 / -45).
CityGML Feature
- LOD1: not available
- LOD2: bldg:WallSurface
- LOD3: bldg:WallSurface
Geometry
gml:MultiSurface siehe auch Handbuch - Teil 1
- Eine Wandfläche besteht nur aus den von außen sichtbaren Flächen.
- Wandüberstände, die das Gebäudevolumen nicht begrenzen, werden entsprechend den Regel für auskragende Bauelemente (Kap. 3.5) modelliert.
- Eine Wandfläche muss aus mehreren Flächen (SurfaceMember) bestehen wenn:
- eine Wandfläche verschiedene Farben oder Texturen hat
4 Wandflächen mit je 3 Fläche (1 Fläche "Orange"; 2 Flächen "Beige")(4x bldg:WallSurface) 4 Wandflächen mit je 2 Flächen (1 Fläche Textur "Putz"; 1 Fläche Textur "Sandstein") (4x bldg:WallSurface) - eine Wandfläche nicht planar ist
- eine Wandfläche verschiedene Farben oder Texturen hat
- Eine Wandfläche kann aus mehreren Flächen (SurfaceMember) bestehen wenn:
Attributes
- bldg:lod2MultiSurface
- Zeigt auf die LOD2 Geometrie
- bldg:lod3MultiSurface
- Zeigt auf die LOD3 Geometrie
- bldg:opening
- Zeigt auf ein CityGML feature bldg:Opening (bldg:Door (siehe Türen) oder bldg:Window (siehe Fenster))
Examples
Eine Wandfläche mit 4 Flächen (1x bldg:WallSurface) nicht empfohlen |
Vier Wandflächen mit je 1 Fläche (4x bldg:WallSurface) |
Vier Wandflächen (drei gerade Wände mit je 1 Flächen und eine gekrümmte Wand mit 12 Flächen) (4x bldg:WallSurface) |
Eine Wandfläche bei ellipsenförmigen oder runden Grundrissen (1x bldg:WallSurface) |
5 Wandflächen durch versetzte Fassadenteile (5x bldg:WallSurface) |
Roof Surfaces (bldg:RoofSurface)
Definition
SIG3D: Exterior, upper boundary surface of a building , building part or building installation, whose primary function is to protect from the effects of weather.
Die Normalen der Dachflächen zeigen in der Regel nach oben.
CityGML Feature
- LOD1: not available
- LOD2: bldg:RoofSurface
- LOD3: bldg:RoofSurface
Geometry
gml:MultiSurface siehe auch Handbuch - Teil 1
- Eine Dachfläche besteht nur aus den von außen sichtbaren Flächen.
- Dachüberstände, die das Gebäudevolumen nicht begrenzen, werden entsprechend den Regel für auskragende Bauelemente (Kap. 3.5) modelliert
Attributes
- bldg:lod2MultiSurface
- Zeigt auf die LOD2 Geometrie
- bldg:lod3MultiSurface
- Zeigt auf die LOD3 Geometrie
- bldg:opening
- Zeigt auf ein CityGML feature bldg:Opening (bldg:Door (siehe Türen) oder bldg:Window (siehe Fenster))
Examples
Satteldach |
Satteldach |
Mischform |
Zeltdach |
Eine Dachfläche mit 2 Flächen (1x bldg:RoofSurface) nicht empfohlen |
Zwei Dachflächen mit je 1 Fläche (2x bldg:RoofSurface) |
Drei Dachflächen (zwei ebene Dachflächen mit je 1 Flächen und eine kegelförmige Dachfläche mit 12 Flächen) (3x bldg:RoofSurface) |
Eine kegelförmigen Dachfläche mit 24 Flächen (1x bldg:RoofSurface) |
Krüppelwalmdach |
Mansardendach |
Bogendach |
Kuppeldach |
4 Dachflächen (4x bldg:RoofSurface) |
Vier Dachflächen (4x bldg:RoofSurface) |
Eine Dachflächen mit 12 Flächen (1x bldg:RoofSurface) |
Eine Dachfläche mit 264 Flächen (1x bldg:RoofSurface) |
Sheddach I |
Sheddach II |
||
5 Dachflächen (5x bldg:RoofSurface) |
10 Dachflächen (10x bldg:RoofSurface) |
Outer Floor Surfaces(bldg:OuterFloorSurface)
Definition
SIG3D: Exterior, upper boundary surface of a building , building part or building installation which is not a roof.
Die Normalen der Äußeren Bodenflächen zeigen in der Regel nach oben.
CityGML Feature
- LOD1: not available
- LOD2: bldg:OuterFloorSurface
- LOD3: bldg:OuterFloorSurface
Geometry
gml:MultiSurface siehe auch Handbuch - Teil 1
- Eine äußere Bodenfläche besteht nur aus den von außen sichtbaren Flächen.
Attributes
- bldg:lod2MultiSurface
- Zeigt auf die LOD2 Geometrie
- bldg:lod3MultiSurface
- Zeigt auf die LOD3 Geometrie
- bldg:opening
- Zeigt auf ein CityGML feature bldg:Opening (bldg:Door (siehe Türen) oder bldg:Window (siehe Fenster))
Examples
Dachterrasse |
Loggia |
Altan |
1 x OuterFloorSurface |
1 x OuterFloorSurface |
1 x OuterFloorSurface |
Outer Ceiling Surface(bldg:OuterCeilingSurface)
Definition
SIG3D: Exterior, lower boundary surface of a building , building part or building installation against air.
Die Normalen der Äußeren Deckenflächen zeigen in der Regel nach unten.
CityGML Feature
- LOD1: not available
- LOD2: bldg:OuterCeilingSurface
- LOD3: bldg:OuterCeilingSurface
Geometry
gml:MultiSurface siehe auch Handbuch - Teil 1
- Eine äußere Deckenfläche besteht nur aus den von außen sichtbaren Flächen.
Attributes
- bldg:lod2MultiSurface
- Zeigt auf die LOD2 Geometrie
- bldg:lod3MultiSurface
- Zeigt auf die LOD3 Geometrie
- bldg:opening
- Zeigt auf ein CityGML feature bldg:Opening (bldg:Door (siehe Türen) oder bldg:Window (siehe Fenster))
Examples
Durchfahrt |
Loggia |
Auskragendes Stockwerk |
1 x OuterCeilingSurface |
1 x OuterCeilingSurface |
1 x OuterCeilingSurface |
Virtual Boundary Surface (bldg:ClosureSurface)
Definition
SIG3D: Exterior or interior boundary surface providing virtual boundaries, typically used to seal holes in volumetric objects.
CityGML Feature
- LOD1: not available
- LOD2: bldg:ClosureSurface
- LOD3: bldg:ClosureSurface
Geometry
gml:MultiSurface siehe auch Handbuch - Teil 1
- Eine virtuelle Begrenzungsfläche des Gebäudes besteht nur aus den von außen sichtbaren (gedachten) Flächen.
Attributes
- bldg:lod2MultiSurface
- Zeigt auf die LOD2 Geometrie
- bldg:lod3MultiSurface
- Zeigt auf die LOD3 Geometrie
- bldg:opening nicht empfohlen
- Zeigt auf ein CityGML feature bldg:Opening (bldg:Door (siehe Türen) oder bldg:Window (siehe Fenster))
Examples
Offene Scheune |
Durchgangsbahnhof |
Parkhaus |
1 x ClosureSurface |
2 x ClosureSurface |
28 x ClosureSurface |
Doors (bldg:Door)
Definition
ISO 6707-1: Construction for closing an opening intended primarily for access or egress or both.
CityGML Feature
- LOD1: not available
- LOD2: not available
- LOD3: bldg:Door
Geometry
gml:MultiSurface siehe auch Handbuch - Teil 1
- Türen können nur aus den von außen sichtbaren Flächen (Fall A, B und C) oder als räumliche Objekte (Fall D) modelliert werden.
Fall A (eine einfache Fläche) |
Fall B (eine einfache Fläche mit Textur) |
Fall C (nur von außen sichtbare Flächen der detaillierten Tür) |
Fall D (Tür als räumliches Objekt) |
- Um eine geschlossen Außenhülle des Gebäudes zu gewährleisten, sollten Türen nicht im geöffneten Zustand (Fall A) sondern im geschlossenen Zustand (Fall B) modelliert werden.
Fall A (Türen geöffnet) |
Fall B (Türen geschlossen) |
Attributes
- bldg:lod3MultiSurface
- Zeigt auf die LOD3 Geometrie
- bldg:address
- Zeigt auf eine Adresse
Examples
Simple Doors |
Simple Doors with Embrasure |
Detailled Doors |
Number of Polygons (Complete Model) = 19 |
Number of Polygons (Complete Model) = 128 |
Number of Polygons (Complete Model) = 3498 |
Windows (bldg:Window)
Definition
SIG3D: Construction for closing an opening in a wall or roof, primarily intended to admit light and / or provide ventilation (cf. ISO 6707).
CityGML Feature
- LOD1: not available
- LOD2: not available
- LOD3: bldg:Window
Geometry
gml:MultiSurface siehe auch Handbuch - Teil 1
- Fenster können nur aus den von außen sichtbaren Flächen (Fall A, B und C) oder als räumliche Objekte (Fall D) modelliert werden.
Fall A (eine einfache Fläche) |
Fall B (eine einfache Fläche mit Textur) |
Fall C (nur von außen sichtbare Flächen des detaillierten Fensters) |
Fall D (Tür als räumliches Objekt) |
- Um eine geschlossen Außenhülle des Gebäudes zu gewährleisten, sollten Fenster nicht im geöffneten Zustand (Fall A) sondern im geschlossenen Zustand (Fall B) modelliert werden.
Fall A (Fenster geöffnet) |
Fall B (Fenster geschlossen) |
Attributes
- bldg:lod3MultiSurface
- Zeigt auf die LOD3 Geometrie
Examples
Simple Window |
Simple Window with Embrasure |
Detailled Window |
Number of Polygons (Complete Model) = 28 |
Number of Polygons (Complete Model) = 412 |
Number of Polygons (Complete Model) = 6269 |
Extended Modeling
The Extended Modeling covers the modeling of frequently appearing architectural building components which significantly form the building's outer appearence. These building components are modeled as building installations as a general rule.
Balconies
Definition
SIG3D: A Balcony is a platform attached to a building which lies above the terrain level and projects from the building structure. It is supported by columns or console brackets, and enclosed with a balustrade [cit. en. Wikipedia]. The word's origin lies in the Italian word "balcone", which itself originates from the old-high-german word "balcho".
CityGML Feature
- LOD1: not available
- LOD2: bldg:BuildingInstallation
- LOD3: bldg:BuildingInstallation
Geometry
- gml:Geometry recommended
- Threshold LOD2:
- Modeling only, if the balcony's depth >= 0,5 m;
- Plane ground-area, if the component's thickness <= 0,5 m;
- Plane side-walls, if the component's thickness <= 0,5 m;
- Modeling only, if the balcony's depth >= 0,5 m;
- Threshold LOD3:
- Modeling only, if the balcony's depth >= 0,2 m;
- Plane ground-Area, if the component's thickness <= 0,2 m;
- Plane side-walls, if the component's thickness <= 0,2 m;
- Modeling only, if the balcony's depth >= 0,2 m;
- Modeling principle
- The building contains all geometry-containing border surfaces.
- The balcony is modeled as a Building Installation with Geometry. That is without semantic differentiation.
- The building's volume references (Xlink) to the corresponding boarder surfaces.
- Threshold LOD2:
Modeling principle of a balcony |
- bldg:boundedBy not recommended
Attributes
- bldg:function
- Balcony (1000); see SIG 3D Codelistrecommendation for bldg:BuildingInstallation --> function
- bldg:boundedBy
- not recommended: A Balcony is considered as one building component which is semantically not subdivided any further.
Examples
Balconies |
|||||
Real Building |
CityGML LOD0 |
CityGML LOD1 |
CityGML LOD2 |
CityGML LOD3 |
|
Above terrain level, projected from the building structure --> Balcony |
Above terrain level, partly projected from the building structure, not bounded by 3 walls --> Balcony (no Loggia) |
Loggias
Definition
SIG3D: A Loggia is an enclosed on top exterior room within the building footprint, which is surrounded by 3 walls at full storey height. From an architectonical point of view, a Loggia (from the Italian) is a room within a building, which opens to the exterior area by means of archs or other constructional appliances. At ground floor level, Loggias create a passage between the interior area and the exterior area. At upper floor levels, Loggias are used as connection passages or as outdoor seating.
CityGML Feature
- LOD1: not available
- LOD2: bldg:BuildingInstallation
- LOD3: bldg:BuildingInstallation
Geometry
- gml:Geometry not recommended
- bldg:boundedBy recommended
- Threshold LOD2:
- Modeling only, if the Loggia's depth >= 0,5 m;
- Threshold LOD3:
- Modeling only, if the Loggia's depth >= 0,2 m;
- Modeling Principle
- The building contains all geometry-containing boundary surfaces
- Threshold LOD2:
- The Loggia (BuildingInstallation) references (Xlink) to the building's corresponding boundary surfaces. If the Loggia's floor is not part of the exterior building structure, it will be modeled as a geometry-containing boarder surface at the Building Installation (? deutsch: ...wird sie als Begrenzungsfläche mit Geometrie am BuildingInstallation modelliert).
- The building's volume references (Xlink) to the building's corresponding boarder surfaces.
Modeling Principle of a Loggia |
Attributes
- bldg:function
- Loggia (1001); see SIG 3D Codelist recommendation for bldg:BuildingInstallation --> function
- bldg:boundedBy
- recommended: A Loggia is considered as a building component which semantically consists of the building's boundary surfaces and possibly an exterior floor surface.
Examples
Loggien |
|||||
Real Building |
ALKIS (German Cadastral Data) |
CityGML LOD0 |
CityGML LOD1 |
CityGML LOD2 |
CityGML LOD3 |
Multi-storey building, Loggias across the whole front-width and height |
|||||
200px Loggias across half the front-width (row house) |
[[image:|200px]] |
[[image:|200px]] Kamen Am Langen Kamp 25 |
|||
200px Projecting Loggias |
* In this example, the geometry is modeled within the lod2Solid
but not within the specified BoundarySurface
elements (opposed to the standard)!
Thoroughfare
Definition
SIG3D: An open Thoroughfare is a part of a building at ground level for vehicles to drive through the building. It is bounded by walls and a roof.
CityGML Feature
- LOD1: not available
- LOD2: bldg:BuildingInstallation
- LOD3: bldg:BuildingInstallation
Geometry
- gml:Geometry not recommended
- bldg:boundedBy recommended
- Threshold LOD2 / LOD3:
- Modeling only, if the Thoroughfare's depth and height >= 2 m;
- Modeling Principle (Thoroughfare in a building)
- The building contains all geometry-containing boundary surfaces.
- The Thoroughfare (BuildingInstallation) references (Xlink) to the building's corresponding boundary surfaces.
- The building's volume references (Xlink) to the building's corresponding boarder surfaces.
Modeling Principle of a Thoroughfare
- Modeling Principle (Shared Thoroughfare through two buildings)
- Each building contains all geometry-containing boundary surfaces
- The Thoroughfare (BuildingInstallation) is assigned to the building which contains the greater part of the Thoroughfare. The Thoroughfare references (Xlink) to the building's corresponding boarder surfaces and complements the Thoroughfare with bounding geometry at the BuildingInstallation.
- The building's volume references (Xlink) to the building's corresponding boarder surfaces.
Modeling Principle of a shared Thoroughfare
Note: The modeling of buildings with a closed building construction is described in Kapitel 3.7Attributes
- bldg:function
- Thoroughfare (1002); see SIG 3D codelist recommendation for bldg:BuildingInstallation --> function
- bldg:boundedBy
- recommended: A Thoroughfare is considered as a building component which semantically consists of the building's boundary surfaces and possibly an exterior floor surface.
Examples
Thoroughfares
Actual Example
ALKIS
CityGML LOD0
CityGML LOD1
CityGML LOD2
CityGML LOD3
200px Two buildings with a shared Thoroughfare
Two buildings with separate Thorouoghfares
Two offset buildings with separate Thoroughfares
200px Two buildings with onesided Thoroughfare
200px Two buildings with a connection section
Dormers / Zwerchhaus (Zwerchgiebel)
Definition
SIG3D: SIG3D: A dormer' is a structural element of a building that protrudes from the plane of a sloping roof surface. Dormers are used, either in original construction or as later additions, to create usable space in the roof of a building by adding headroom and usually also by enabling addition of windows [Wikipedia].
A dormer does not lie on the same plane as the building's exterior wall. The dormer (or the dormer's footprint) has a minimum offset of 0,5 m and lies inside the building's footprint.
SIG3D: The Zwerchhaus is a one or more story installation of a sloping roof surface. It consists of a gable and its own roof. The !!!Zwerchgiebel!!! follows the exterior wall's building line. That represents the difference between a !!!Zwerchhaus!!! and a gable, because a gable does not have to follow the building line. The roof of the !!!Zwerchhaus!!! is often designed as a ridge roof. The ridge follows cross to the main roof's ridge. So the rainwater pipes continue in an orthogonal way to each other.
Note: The zwerchhaus is not modeled as a part of the building installation, but as a building's boundary surface itself.
CityGML Feature
- LOD1: not available
- LOD2: bldg:BuildingInstallation
- LOD3: bldg:BuildingInstallation
Geometry
- gml:Geometry not recommended
- bldg:boundedBy recommended
- Threshold LOD2:
- Modeling only, if the dormer's height >= 2 m;
- Threshold LOD3:
- Modeling Principle
- The building contains all geometry-containing boundary surfaces of the building structure. To close the building's volume, a ClosureSurface is modeled into the roof's gap.
- The dormer (BuildingInstallation) contains all geometry-containing boundary surfaces of the dormer. To close the volume, either a ClosureSurface is modeled or it is closed by referencing to the building's corresponding ClosureSurface (Xlink to OrientableSurface).
- The building's volume, the building structure's volume and the volume of the dormer (CompositeSolid) reference (Xlink)to the corresponding boundary surfaces of the building structure and dormer.
- Threshold LOD2:
Modelling Principle of a dormer Attributes
- bldg:function
- Dormer (1003); see SIG 3D codelisten recommendation forbldg:BuildingInstallation --> function
- bldg:boundedBy
- recommended: A dormer is considered as a building component which semantically consists of the building's boundary surfaces.
Examples
Dormer
Actual Example
CityGML LOD0
CityGML LOD1
CityGML LOD2
CityGML LOD3
Zwerchhaus (Zwerchgiebel)
Actual Example
CityGML LOD0
CityGML LOD1
CityGML LOD2
CityGML LOD3
Arcades / Architrav
Definition
SIG3D: Eine Arkade (lateinisch arcus: Bogen) bezeichnet in der Architektur einen von Pfeilern oder Säulen getragenen Bogen. Der Bogen lässt wesentlich größere Spannweiten zu als dies beim Architrav möglich ist [Wikipedia].
SIG3D: Der Architrav (von italienisch architrave, aus griechisch ἀρχι, archi-, Ober-, Haupt- und lateinisch trabs, Balken) ist ein auf einer Stützenreihe ruhender Horizontalbalken. In der Antike wurde der Architrav auch Epistyl genannt, da er hier meist auf Säulen ruht (Epistyl von griechisch auf den Säulen liegend)[Wikipedia].
CityGML Feature
- LOD1: not available
- LOD2: bldg:BuildingInstallation
- LOD3: bldg:BuildingInstallation
Geometry
- gml:Geometry nicht empfohlen
- bldg:boundedBy empfohlen
- Schwellenwerte LOD2:
- Schwellenwerte für Modellierung von Stützen: alle Seiten der BoundingBox der Stütze >= 0,5 m
- Modellierungsprinzip
- Das Gebäude enthält alle Begrenzungsflächen mit Geometrie
- Die Arkade (BuildingInstallation) referenziert (Xlink) auf die entsprechenden Begrenzungsflächen des Gebäudes.
- Das Gebäudevolumen referenziert (Xlink) auf die entsprechenden Begrenzungsflächen des Gebäudes
- Schwellenwerte LOD2:
Modellierungsprinzip einer Arkade Attributes
- bldg:function
- Arkade (1009); siehe SIG 3D Codelistenvorschlag für bldg:BuildingInstallation --> function
- bldg:boundedBy
- empfohlen: Eine Arkade wird als ein Bauteil angesehen, das sich semantisch aus Begrenzungsflächen des Gebäudes und evtl. einer äußeren Bodenflächen zusammensetzt.
Examples
Arkaden
Reales Beispiel
ALKIS
CityGML LOD0
CityGML LOD1
CityGML LOD2
CityGML LOD3
Arkade
Real Building
CityGML LOD0
CityGML LOD1
CityGML LOD2
CityGML LOD3
- Threshold LOD2 / LOD3: