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releasenotes [2020/02/23 14:25] christian [Typing] |
releasenotes [2020/02/23 15:42] christian [CMaps] |
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| ==== PostScript ==== | ==== PostScript ==== | ||
| - | Added [[PostScript]] | + | Added **[[PostScript]]** to the PDFtalk |
| The package **[PostScript]** implements some low level methods which are used by PDFtalk. | The package **[PostScript]** implements some low level methods which are used by PDFtalk. | ||
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| ==== CMaps ==== | ==== CMaps ==== | ||
| - | Added [[CMap]] to the **{PDFtalk Fonts}** bundle. | + | Added **[[CMap]]** to the **{PDFtalk Fonts}** bundle. |
| **CMaps** are PostScript programs defining complex code mappings. The mechanism is very general and allows for variable byte length encodings. Because of its generality, CMaps are used by some PDF writers to even encode simple mappings. Hence, it is necessary to fully implement CMaps in order to decode PDF text. | **CMaps** are PostScript programs defining complex code mappings. The mechanism is very general and allows for variable byte length encodings. Because of its generality, CMaps are used by some PDF writers to even encode simple mappings. Hence, it is necessary to fully implement CMaps in order to decode PDF text. | ||
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| Therefore, I put them into a seperate package (outside of the runtime, but part of the project bundle): **[PostScript CMap instances]**. The CMaps are constructed from the source methods lazily when needed. If the package is not loaded, the source of a requested CMap is downloaded from GitHub, which is slower. | Therefore, I put them into a seperate package (outside of the runtime, but part of the project bundle): **[PostScript CMap instances]**. The CMaps are constructed from the source methods lazily when needed. If the package is not loaded, the source of a requested CMap is downloaded from GitHub, which is slower. | ||
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| + | === Known problem === | ||
| + | |||
| + | The PDF specification allows bfchar-mappings to have a string of UTF-16BE characters as destination. This is not yet implemented. | ||
| + | |||
| ==== Typing ==== | ==== Typing ==== | ||
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| Textstring does not need to be differenciated. We can rely on VisualWorks handling of multi byte strings. | Textstring does not need to be differenciated. We can rely on VisualWorks handling of multi byte strings. | ||
| - | |||
| - | ==== Known problem ==== | ||
| - | |||
| - | The PDF specification allows bfchar-mappings to have a string of UTF-16BE characters as destination. This is not yet implemented. | ||
| ===== PDFtalk 2.2 ===== | ===== PDFtalk 2.2 ===== | ||