8 Conformance

8.1 Introduction

8.1.1 Table of contents

Table 8.1 contains the table of contents for this clause.

Table 8.1 -- Table of contents, Concepts

8.1.2 Objectives

This clause addresses conformance of VRML XML encoded files and conformance of VRML  generators and VRML XML browsers that support the VRML XML encoding. Thus, this clause addresses conformance to X3D.

The primary objectives of the specifications in this clause are:

1. to promote interoperability by eliminating arbitrary subsets of, or extensions to, ISO/IEC 14772;
2. to promote uniformity in the development of conformance tests;
3. to promote consistent results across X3D browsers and VRML browsers in general;
4. to facilitate automated test generation.

8.1.3 Scope

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

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

This clause addresses the VRML data stream and implementation requirements as related to the XML encoding. Implementation requirements include the latitude allowed for VRML generators and VRML browsers supporting the XML encoding. 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 VRML file.

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

8.2 Conformance

8.2.1 Conformance of VRML files

An XML encoded X3D file is syntactically correct according to ISO/IEC 14772 if the following conditions are met:

1. The VRML file contains as its first element a VRML header comment (see ISO/IEC 14772l-1:  4.2.2, Header).
2. The XML encoded portion of the X3D file content contains as its first element an XML document type declaration, as defined in section 5.1 of 2.[XML].
3. The XML encoded portion of an X3D file passes an XML parsing "validation" against the X3D Document Type Definition, as defined in section 5.1 of 2.[XML].
4. All XML entities, elements and attributes contained therein match the functional specification of the corresponding entities of ISO/IEC 14772-1, for the profile specified in the header statement.
5. The sequence of in the XML entities, elements and attributes within the X3D file obeys the relationships specified in ISO/IEC 14772-1 producing the structure specified in ISO/IEC 14772-1.
6. No entity, element or attribute names appear in the X3D file other than those specified in ISO/IEC 14772-1, and defined in Annex A--DTD.
7. The file is encoded according to the rules of ISO/IEC 14772-4.
8. It does not contain XML content that generates behavior described as undefined elsewhere in this specification.

A VRML XML encoded file conforms to the core profile if:

9. It is syntactically correct.
10. It meets the restrictions of the profile as defined in ISO/IEC 14772-1--8. Core profile.

A VRML XML encoded file conforms to the base profile if:

11. It is syntactically correct.
12. It meets the restrictions of the profile as defined in ISO/IEC 14772-1--9. Base profile.

A VRML UTF-8 encoded file conforms to other profiles if:

13. It is syntactically correct.
14. It meets the restrictions of the profile as defined in the specification for that profile.

8.2.2 Conformance of VRML generators

A VRML XML encoding generator conforms to this part of ISO/IEC 14772 if all VRML files that are generated are syntactically correct.

A VRML XML encoding generator conforms to a particular profile if it can be configured such that all VRML files generated conform to that particular profile.

8.2.3 Conformance of VRML browsers

A VRML browser that supports the XML encoding conforms to a particular profile if:

1. It minimally parses XML input in a non-validating mode, as described in section 5.1 of 2.[XML].
2. It minimally parses only those entities defined for non-validating parsers in section 5.1 of 2.[XML].
3. It generates all appropriate warning and error messages for "well-formedness" constraints defined in section 4.3.2 of 2.[XML] for parsed entities.
4. As describe in 4.2.3, the browser does not generate a fatal error message and halt processing, as defined in section 1.2 of the 2.[XML], but omits any erroneous constructs, and produces at a minimum a well formed, but possibly empty scene.
5. It is able to read any VRML XML encoded file that conforms to that particular profile.
6. It presents the graphical and audio characteristics of the VRML nodes in any VRML XML encoded file that conforms to the that particular profile, within the latitude defined the specification for that particular profile.
7. It correctly handles user interaction and generation of events as specified in ISO/IEC 14772-1, within the latitude defined in the specification for that particular profile.
8. It satisfies the requirements of that particular profile in regard to minimum support requirements as defined in the specification for that particular profile.
9. It satisfies the general conformance requirements for browsers as stated in ISO/IEC 14772-1--7. Conformance.