You are here: Encoding > Unicode > Training
Short URL: https://scripts.sil.org/UTTLegacyMap
Creating a Chart of Your Legacy Mapping
Using the Legacy Mapping Workbook
Home:How to Write a Conversion Mapping for your Legacy Font
Goals for this Step:
This page explains how to create a chart of your legacy to Unicode mapping, using an Excel spreadsheet. This chart is a means to visually verify that you have chosen the correct Unicode character for each of the characters in your legacy font.
This step is part of the procedure How to Write a Conversion Mapping for your Legacy Font.
- If you haven't already, download and unzip the file
- Place this file in your working folder. The Legacy Mapping Workbook.xls is an Excel spreadsheet containing 4 worksheets. When you first open it, Excel should ask you whether to enable macros. In order for the file to work properly, you must say "Enable macros". If you have questions about security, contact your computer support person.
- At the bottom of the screen you will see the 4 worksheet names: Instructions, Legacy Mapping, UnicodeDate, CP1252. You do not have to look at or understand the last two worksheets. But they have to be there for the spreadsheet to work correctly.
- Read the Instructions for Use. Follow the directions under "Setting Up Your Fonts". You may prefer to print these before following them.
- Now click the tab at the bottom of the screen called "Legacy Mapping". Column D should have the standard ASCII (shown in Arial font) glyphs from 32-255. Column E (Legacy Glyph) should show your legacy glyphs from 32-255. Click on a glyph in Column E and verify that your font name is shown in the Font box. If not, you need to re-do the "Setting Up Your Fonts" directions.
- Check that the glyphs listed in column E match those in your YourFont.doc chart (from What's in Your Font?). The order should be identical.
- Save the workbook to your work folder. You may save as the same name or a different one. But plan to keep the .zip file for future projects or to start this one over, if necessary.
How to type a Unicode mapping in the Legacy Mapping Workbook
- Click the Instructions worksheet tab at the bottom of the screen. Read the instructions "Legacy Mappings Worksheet". If you do not have the Arial Unicode MS font on your machine, we recommend Doulos SIL or Gentium fonts. Follow the instructions in the workbook to apply one of these fonts to the Unicode font style, if needed. You may also need to use one of these fonts if Arial Unicode MS does not have your characters. And you will need to find and use an appropriate non-Roman Unicode font if your legacy font is non-Roman (not ABCs).
- Click the Legacy Mapping worksheet tab. Scroll down to row 68 (decimal 97 or the 'a' row). Under column F, type U+0061. Press Enter . The letter a should appear in Column G. Type 0062 in the next row. Press Enter . Type 63 in the next row. Press Enter . You should now see the characters a, b, and c in column G. If not, you have a setup problem. These are the three ways you can enter a codepoint in column F. Choose one and stick with it.
- The goal now is to get Columns E and G to match, by inserting the correct Unicode number in Column F. This will be your goal for the next 2 to 3 weeks. Now delete the data you have typed in Column F.
- Look at Columns D and E. Any place the characters in both columns match, you may use the Unicode codepoint shown in Column C as the mapping (type the number in Column F, using your chosen format. (Hint: Don't attempt to cut & paste in this workbook. See the note below.)
- Any place the characters do not match, you will need to determine the proper Unicode codepoint number for the character shown in your legacy font (Column E).
Warning! Accidental Erasure Possible
Excel does not automatically protect your data against accidental erasure or typos. Be careful to only type in columns F (Proposed Mapping: Unicode(s)) and H (Notes) of the Legacy Mapping Workbook. You should not change the data in any of the other columns, including Column G. Even though it appears empty, it is not. Do not attempt to cut and paste from other columns in this workbook.
Getting Columns E and G to match
This can be a lengthy process, especially if you have lots of characters that are different between Columns D and E. On average, you can expect to take 2-3 weeks determining what Unicode codepoints are needed. That step and filling in this chart will be covered later in Edit Your Mapping. But first, we will look at some suggestions for shortening this time.
2008-02-26 JW: reviewed, minor updates
2005-09-27 JW: Page created
© 2003-2023 SIL International, all rights reserved, unless otherwise noted elsewhere on this page.