Using Unicode extended code pages
Unicode Extended Code Pages (ECP) are code pages with additional information used by OpenType and TrueType fonts. This is a introduction for using extended code pages:
- If OpenType and TrueType fonts are used without ECP, Unicode scalars must be defined in the hardcoded GUM (GCGID-to-Unicode-Mapping, where GCGID stands for Graphic Character Global IDentifier) table resident in the printer or code points will be undefined. While the use of predetermined mappings might meet many needs, if customization of GCGID to Unicode mappings is required, an extended code page must be used.
- The extended code pages can be used on printers that do not support the extensions. However, the extensions will be stripped out of the code page as it is downloaded to the printer appearing as if an unextended code page was used.
- The extended code pages are files on disk just like unextended code pages. The search order defined in the InfoPrint Manager: Reference in the description of the resource-context-font attribute still applies. However, a new file extension of .ECP is supported for all code pages. Inside the same directory, a code page with the .ECP file extension will be selected before any other code page with a matching name but a different file extension.
- File extensions are secondary search criteria. The search order of directories is the primary search criterion when searching for any code page resource, including Unicode extended code pages. The first possible match on the resource name is used. For example, there might be two code pages called T1USV500.ECP and T1USV500. The T1USV500.ECP code page is located in a directory only specified by resource-context. The T1USV500 code page is located in a directory specified in resource-context-font. In this case, the T1USV500 code page is used. Conversely, if T1USV500.ECP and T1USV500 are located in the same directory, the T1USV500.ECP code page is used.
- Code pages created or modified by the AFP Resource Installer will always have an .ECP file extension. Use installation software to manage the installation of this new kind of resource.
- To force a code page to be downloaded instead of using a printer resident code page and to prevent run-time substitution of code pages, do the procedure Using the 'no resident' version of the sample grid files.