The SEDRIS Data Representation Model
APPENDIX B - Constraints
Image Anchor Spatial Reference Frame

Definition

Consider an <Image Anchor> instance A.

  1. The <Location> instances in the scope of A shall be valid within the spatial reference frame specified by A's srf_info.

  2. A shall be either a component of one or more <Image> instances or of one or more <Image Mapping Function> instances, but not both.

  3. If A is a component of an <Image Mapping Function> instance F, and if F appears within the context of some spatial reference frame S, A's srf_info shall equal those specified by S.

Rationale

Every <Location> is required to be valid within the context of the spatial reference frame in which it is defined. (In this sense, "valid" includes the SRM concept of "extended" coordinates.) To allow an <Image Mapping Function> specified with an <Image Anchor> to be applied correctly to the textured objects, its spatial reference frame and theirs are required to be compatible.

Example

No Example supplied.

FAQs

No FAQs supplied.

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Last updated: July 16, 2004 Copyright © 2004 SEDRIS™