SIST EN ISO 25178-72:2017/A1:2020

SLOVENSKI STANDARD
01-december-2020
Specifikacija geometrijskih veličin izdelka (GPS) - Tekstura površine: ravna - 72.
del: XML-format datoteke x3p - Dopolnilo A1 (ISO 25178-72:2017/Amd 1:2020)
Geometrical product specifications (GPS) - Surface texture: Areal - Part 72: XML file
format x3p - Amendment 1 (ISO 25178-72:2017/Amd 1:2020)
Geometrische Produktspezifikation (GPS) - Oberflächenbeschaffenheit: Flächenhaft -
Teil 72: XML-Dateiformat x3p - Änderung 1 (ISO 25178-72:2017/Amd 1:2020)
Spécification géométrique des produits (GPS) - État de surface: Surfacique - Partie 72:
Format de fichier XML x3p - Amendement 1 (ISO 25178-72:2017/Amd 1:2020)
Ta slovenski standard je istoveten z: EN ISO 25178-72:2017/A1:2020
ICS:
17.040.20 Lastnosti površin Properties of surfaces
17.040.40 Specifikacija geometrijskih Geometrical Product
veličin izdelka (GPS) Specification (GPS)
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EN ISO 25178-
EUROPEAN STANDARD
72:2017/A1
NORME EUROPÉENNE
EUROPÄISCHE NORM
September 2020
ICS 17.040.20
English Version
Geometrical product specifications (GPS) - Surface texture:
Areal - Part 72: XML file format x3p - Amendment 1 (ISO
25178-72:2017/Amd 1:2020)
Spécification géométrique des produits (GPS) - État de Geometrische Produktspezifikationen (GPS) -
surface: Surfacique - Partie 72: Format de fichier XML Oberflächenbeschaffenheit: Flächenhaft - Teil 72: XML-
x3p - Amendement 1 (ISO 25178-72:2017/Amd Dateiformat x3p - Änderung 1 (ISO 25178-
1:2020) 72:2017/Amd 1:2020)
This amendment A1 modifies the European Standard EN ISO 25178-72:2017; it was approved by CEN on 25 August 2020.

CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for inclusion of
this amendment into the relevant national standard without any alteration. Up-to-date lists and bibliographical references
concerning such national standards may be obtained on application to the CEN-CENELEC Management Centre or to any CEN
member.
This amendment exists in three official versions (English, French, German). A version in any other language made by translation
under the responsibility of a CEN member into its own language and notified to the CEN-CENELEC Management Centre has the
same status as the official versions.

CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia,
Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway,
Poland, Portugal, Republic of North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and
United Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION

EUROPÄISCHES KOMITEE FÜR NORMUNG

CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels
© 2020 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 25178-72:2017/A1:2020 E
worldwide for CEN national Members.

Contents Page
European foreword . 3

European foreword
This document (EN ISO 25178-72:2017/A1:2020) has been prepared by Technical Committee ISO/TC
213 "Dimensional and geometrical product specifications and verification" in collaboration with
Technical Committee CEN/TC 290 “Dimensional and geometrical product specification and verification”
the secretariat of which is held by AFNOR.
This Amendment to the European Standard EN ISO 25178-72:2017 shall be given the status of a
national standard, either by publication of an identical text or by endorsement, at the latest by March
2021, and conflicting national standards shall be withdrawn at the latest by March 2021.
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CEN shall not be held responsible for identifying any or all such patent rights.
According to the CEN-CENELEC Internal Regulations, the national standards organizations of the
following countries are bound to implement this European Standard: Austria, Belgium, Bulgaria,
Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland,
Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Republic of
North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and the
United Kingdom.
Endorsement notice
The text of ISO 25178-72:2017/Amd 1:2020 has been approved by CEN as EN ISO 25178-
72:2017/A1:2020 without any modification.

INTERNATIONAL ISO
STANDARD 25178-72
First edition
2017-05
AMENDMENT 1
2020-09
Geometrical product specifications
(GPS) — Surface texture: Areal —
Part 72:
XML file format x3p
AMENDMENT 1
Spécification géométrique des produits (GPS) — État de surface:
Surfacique —
Partie 72: Format de fichier XML x3p
AMENDEMENT 1
Reference number
ISO 25178-72:2017/Amd.1:2020(E)
©
ISO 2020
ISO 25178-72:2017/Amd.1:2020(E)

© ISO 2020
All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may
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Phone: +41 22 749 01 11
Email: copyright@iso.org
Website: www.iso.org
Published in Switzerland
ii © ISO 2020 – All rights reserved

ISO 25178-72:2017/Amd.1:2020(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.
The procedures used to develop this document and those intended for its further maintenance are
described in the ISO/IEC Directives, Part 1. In particular, the different approval criteria needed for the
different types of ISO documents should be noted. This document was drafted in accordance with the
editorial rules of the ISO/IEC Directives, Part 2 (see www .iso .org/ directives).
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. Details of
any patent rights identified during the development of the document will be in the Introduction and/or
on the ISO list of patent declarations received (see www .iso .org/ patents).
Any trade name used in this document is information given for the convenience of users and does not
constitute an endorsement.
For an explanation of the voluntary nature of standards, the meaning of ISO specific terms and
expressions related to conformity assessment, as well as information about ISO's adherence to the
World Trade Organization (WTO) principles in the Technical Barriers to Trade (TBT), see www .iso .org/
iso/ foreword .html.
This document was prepared by Technical Committee ISO/TC 213, Dimensional and geometrical product
specifications and verification, in collaboration with the European Committee for Standardization (CEN)
Technical Committee CEN/TC 290, Dimensional and geometrical product specification and verification, in
accordance with the Agreement on technical cooperation between ISO and CEN (Vienna Agreement).
Any feedback or questions on this document should be directed to the user’s national standards body. A
complete listing of these bodies can be found at www .iso .org/ members .html.
ISO 25178-72:2017/Amd.1:2020(E)
Geometrical product specifications (GPS) — Surface
texture: Areal —
Part 72:
XML file format x3p
AMENDMENT 1
Page 3, 3.14
Replace with:
3.14
global coordinate system
three-dimensional, right-handed coordinate system in which the position and orientation of the original
point cloud is defined
Page 3, 3.15
Replace with:
3.15
view coordinate system
three-dimensional, right-handed coordinate system in which the stored point coordinates are defined
Note 1 to entry: Conversion from view coordinates (x, y, z) to global coordinates (X, Y, Z) could involve rotation
and translation.
Note 2 to entry: Many instruments measure the z coordinates of surface points in the view coordinate system at
predefined values of the respective x and y coordinates.

Page 5, 5.4.4
Replace EXAMPLE with:
EXAMPLE A vendor specific extension could be a vendor specific xml file or any other type of file.

Page 5, 5.5.3.1
Replace with:
5.5.3.1  Revision
The Revision record shall contain the string “ISO25178 -72: 2017/ DAM1”.
ISO 25178-72:2017/Amd.1:2020(E)

Page 7, 5.5.3.3.2.1
Replace with:
5.5.3.3.2.1  General
The AxisType element shall be one of the letters "I" for incremental axis or "A" for absolute axis. The x
and y coordinates can either be of incremental axis type or absolute axis type. The z coordinates shall
be of absolute axis type.
Page 7, 5.5.3.3.2.3
Replace with:
5.5.3.3.2.3  Absolute axis type
An absolute axis type shall be used for the explicit storage of x, y and z coordinates. Coordinates of
absolute axis type shall be stored as dimensionless values. The dimensional coordinate shall be
calculated by multiplying the stored value by a scaling factor I in metres.
NOTE 1 Compared with an incremental axis type, the absolute axis type causes a higher memory usage for
x and y coordinates. The amount of memory used is as large as for the z coordinate because for each 3D point
the x and y coordinate is stored separately. Therefore, it is recommended that incremental x and y axes are used
whenever possible, i.e. when point spacing is regular and homogenous.
NOTE 2 The constant I is usually called calibration factor.

Page 8, 5.5.3.3.4
Replace with:
5.5.3.3.4  Increment
The Increment element shall contain a positive length value in metres specifying either the increment
of the incremental axis or the scaling factor of the absolute axis. The increment shall not be zero. The
increment values for the x, y and z axes are named with the symbols I , I and I .
x y z
NOTE The element name Increment is used due to historical reasons.

2 © ISO 2020 – All rights reserved

ISO 25178-72:2017/Amd.1:2020(E)

Page 8, 5.5.3.5
Replace with:
5.5.3.5  Coordinate transformation
The calculation of the global coordinates from the view coordinates of the stored 3D points is made
using Formula (2):
   
X rr r I 00 x O
 
   
11 12 13 x x
   
 
   
   
Y = rr r ⋅ 0 I 0 ⋅ y + O (2)
 
   
21 22 23 yy y
   
 
   
   
Z rr r z
   
 31 32 33  00 I O
   
z z
where
X, Y, Z are the global coordinates in metres;
x, y, z are the dimensionless view coordinates;
rr… are the rotation elements;
11 33
I , I , I are the increment values in metres or scaling factors in metres;
x y z
O , O , O are the offset values in metres.
x y z
Page 10, 5.5.5.2.2
Replace with:
5.5.5.2.2  MatrixDimension
The MatrixDimension element shall contain the three elements SizeX, SizeY and SizeZ, defining the size
of the data matrix in u, v and w dimensions.
The names of the elements SizeX, SizeY and SizeZ could be misleading because they do not necessarily
define anything directly related to x, y and z dimensions of the 3D coordinates. In datasets with
incremental x and y axes the following relation between u and x, as well as between v and y, holds:
xu=−11, yv=−
where
uv==11,.,SizeXS,,., izeY
EXAMPLE 1 Definition of a matrix with 4 × 4 points and one surface layer:
4 4 1
EXAMPLE 2 Definition of a matrix for a profile data set with 10 points and two profile layers:
10 1 2

ISO 25178-72:2017/Amd.1:2020(E)

Page 13, 5.5.5.3.5
Replace with:
5.5.5.3.5  Binary validity file format
The binary validity file shall be written as a packed array of bits. The bit index j into the packed array
shall be calculated in the same way as described for the data list in 5.5.5.3.2.1. From the bit index, the
byte position j and the bit position j in the packed array shall be calculated using Formulae (3) and (4):
8 1
j
 
j = (3)
 
 8
jj=−8⋅j (4)
The notation calculates the next smaller integer for a real number.
EXAMPLE See Table 1 for a sample calculation of the indices.
Table 1 — Example calculation of byte and bit index for binary validity file
j 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16
0 0 0 0 0 0 0 0 1 1 1 1 1 1 1 1 2
j
0 1 2 3 4 5 6 7 0 1 2 3 4 5 6 7 0
j
Page 14, 5.5.7
Replace with:
5.5.7  Vendor specific extensions
The VendorSpecificID element shall be used to identify extensions of the x3p file format. This tag
shall contain a vendor specific ID, which is a URI created by the vendor identifying a vendor specific
extension file. The URI shall consist of a worldwide unique domain name, an optional file path and the
vendor specific extension file name itself. When writing an x3p file, the vendor specific extension file
shall be placed in the zip-container under the given URI, replacing "." with "\" in the domain name.
When reading an x3p file an unknown VendorSpecificID element can be safely ignored as well as all
optional contents of the zip container. The number of VendorSpecificID elements is unbounded.
NOTE 1 Name collisions are avoided if a unique URL is used to construct a path to the vendor specific
extension file.
NOTE 2 An x3p file contai
...