Class PDFGlyphWidthTable
- java.lang.Object
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- com.inductiveautomation.rm.pdf.reader.PDFGlyphWidthTable
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public class PDFGlyphWidthTable extends java.lang.Object
This class is used to map cids to widths. Widths are always indexed by character code. For single byte fonts, we allocate a single 256 entry array for quick character code -> width lookup. Instead of using a 64K entry array for 2 byte fonts, widths are represented by a sorted array of WidthTableEntries.The pdf format for widths looks like: [cid [w1 w2 w3] cidfirst cidlast w4 cid2 [w5 w6 w7 w8]]
so the widths for a range of cids can be specified as an array of widths, or by a single width that applies to every cid in the range.
All WidthTableEntries have a startcid & endcid range and can then hold either a) an array of endcid-startcid+1 floats b) a single float
The widthtable can then do a binary search through the table to find the specific widthtable entry. The worst possible case would be a table of 64k entries, each describing a single glyph, and a search for a glyph through this would take log2(65536) = 16 hops through a huge table. Any fontlist this large would actually just revert to a single entry with 64k widths, so there would be no searching. Average case would be a much smaller, especially since this is often used for font subsets.
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Constructor Summary
Constructors Constructor Description PDFGlyphWidthTable(java.util.List pdfwidths, java.lang.Object defwidth)
Main constructor.
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Method Summary
All Methods Instance Methods Concrete Methods Modifier and Type Method Description float
getWidth(int cid)
Binary search the list and return the width
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