7.1 Introduction

7.1.1 Table of contents

7.1.2 Objectives

This clause addresses conformance of Classic VRML encoded files and conformance of X3D generators and X3D browsers that support the Classic VRML encoding.

The primary objectives of the specifications in this clause are:

1. to promote interoperability by eliminating arbitrary subsets of, or extensions to, ISO/IEC 19775-1;
2. to promote uniformity in the development of conformance tests;
3. to promote consistent results across X3D browsers;
4. to facilitate automated test generation.

7.1.3 Scope

Conformance is defined for Classic VRML encoded files and for X3D browsers which support Classic VRML encoded files. For X3D generators, conformance guidelines are presented for enhancing the likelihood of successful interoperability.

A concept of conformance to an X3D profile is introduced along with the rules which apply to this encoding.

This clause addresses the X3D data stream and implementation requirements. Implementation requirements include the latitude allowed for X3D generators and X3D browsers. This clause does not directly address the environmental, performance, or resource requirements of the generator or browser.

This clause does not define the application requirements or dictate application functional content within a X3D file.

The scope of this clause is limited to rules for the open interchange of VRML content using the UTF-8 encoding.

7.2 Conformance

7.2.1 Conformance of Classic VRML encoded files

An X3D file is syntactically correct according to this part of ISO/IEC 19776 if the following conditions are met:

1. The X3D file contains as its first element an X3D header statement (see 4.3.2.2, Header statement syntax).
2. The X3D file contains as its second element an X3D PROFILE statement (see 4.3.2.3, PROFILE statement syntax).
3. Any COMPONENT statements (see 4.3.2.4, COMPONENT statement syntax) in the X3D file immediately follow the PROFILE statement.
4. All entities contained therein match the functional specification of the corresponding entities of ISO/IEC 19775-1 (see 2.[I19775-1]). The X3D file shall obey the relationships defined in the formal grammar and all other syntactic requirements.
5. The sequence of entities in the Classic VRML encoded file obeys the relationships specified in ISO/IEC 19775-1 producing the structure specified in ISO/IEC 19775-1.
6. All field values in the Classic VRML encoded file obey the relationships specified in ISO/IEC 19775-1 producing the structure specified in ISO/IEC 19775-1.
7. No nodes appear in the X3D file other than those allowed by ISO/IEC 19775-1 unless required for the encoding technique or those defined by the PROTO or EXTERNPROTO entities.
8. The X3D file is encoded according to the rules of this part of ISO/IEC 19776.
9. It does not contain behaviour described as undefined in ISO/IEC 19775-1.

A Classic VMRL encoded X3D file conforms to the a particular profile if:

10. It is syntactically correct.
11. It meets the restrictions of the profile as defined in the annexes of ISO/IEC 19775-1 or in other parts of ISO/IEC 19775.

7.2.2 Conformance of Classic VRML encoding generators

A Classic VRML encoding generator conforms to this part of ISO/IEC 19776 if all X3D files that are generated are syntactically correct according to the provisions of this part of ISO/IEC 19776.

A Classic VRML encoding generator conforms to a particular profile if it can be configured such that all X3D files generated while in that configuration conform to that particular profile.

7.2.3 Conformance of Classic VRML encoding browsers

An X3D browser that supports the Classic VRML encoding conforms to a particular profile if:

1. It is able to read any Classic VRML encoded file that conforms to that particular profile.
2. It presents the graphical and audio characteristics of the X3D nodes in any Classic VRML encoded file that conforms to the that particular profile, within the latitude defined the specification for that particular profile.
3. It correctly handles user interaction and generation of events as specified in ISO/IEC 19775-1, within the latitude defined in the specification for that particular profile as defined in the annexes of ISO/IEC 19775-1 or in other parts of ISO/IEC 19775.
4. It satisfies the requirements of that particular profile in regard to minimum support requirements as defined in the specification for that particular profile.
5. It satisfies the general conformance requirements for browsers as stated in 6, Conformance of ISO/IEC 19775-1 (see 2.[I19775-1])