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cmap [2020/02/23 11:17]
christian [Mappings outside the codespace]
cmap [2020/02/23 13:43]
christian [Mappings outside the codespace]
Line 126: Line 126:
 ===== Monster from the wild ===== ===== Monster from the wild =====
  
 +CMaps are not well defined. Therefore, there are some interesting variations of them in the wild. Here is a small selection of some issues.
 +==== Codespace problems ====
  
-==== Mappings outside the codespace ====+=== Wrong code length ===
  
-single byte mappings in a double byte codespace+<code postscript> 
 +%... 
 +1 begincodespacerange 
 +<0000> <FFFF> 
 +endcodespacerange 
 +27 beginbfchar 
 +<20> <0020> 
 +<2E> <002E> 
 +<43> <0043> 
 +<44> <0044> 
 +<45> <0045> 
 +%... 
 +</code>
  
-Sometimes CMaps define mappings which are not covered by the codespace ranges. This can be seen very often in the wild. These illegal mappings are collected into the ''#unmapped'' variable of a Mappings object.+Here are single byte mappings in a double byte codespace which is not correct according to the documentation.
  
-==== Wrong PostScript ====+This can be seen often. These illegal mappings are collected into the ''#unmapped'' variable of a Mappings object.
  
-using /find instead of /findresource +=== Mappings outside the codespace === 
 + 
 +<code postscript> 
 +%... 
 +1 begincodespacerange 
 +<0001> <1004> 
 +endcodespacerange 
 +11 beginbfchar 
 +<0003> <00A0> 
 +<0005> <0022> 
 +<0008> <0025> 
 +<000F> <002C> 
 +<0010> <00AD> 
 +%... 
 +</code> 
 + 
 +Here, only the first mapping matches the code space. All others fall outside of it. 
 + 
 +==== Wrong PostScript ====
  
-See [[postscript#exception_handling_example]]+On one occasion, I saw a CMap where the PostScript used a non-existing operator (''/find'' instead of ''/findresource''). See the [[postscript#exception_handling_example]] on the PostScript page.
 ==== Prevent copying ==== ==== Prevent copying ====
  
  • cmap.txt
  • Last modified: 2020/02/23 14:33
  • by christian