Adobe 12020596 User Guide - Page 113
Masked Images, 9.1 Form Dictionaries, 9.3 Reference XObjects, 2.5 Text Rendering Mode, 3.2 Text-
View all Adobe 12020596 manuals
Add to My Manuals
Save this manual to your list of manuals |
Page 113 highlights
Adobe Acrobat SDK Adobe® Supplement to the ISO 32000 Implementation Notes Implementation Notes to the PDF Reference, sixth edition 113 4.8.5 Masked Images 54. Explicit masking and color key masking are features of PostScript LanguageLevel 3. Acrobat 4.0 and later versions do not attempt to emulate the effect of masked images when printing to LanguageLevel 1 or LanguageLevel 2 output devices; they print the base image without the mask. The Acrobat 4.0 viewer displays masked images, but only when the amount of data in the mask is below a certain limit. Above that, the viewer displays the base image without the mask. 4.9.1 Form Dictionaries 55. All Acrobat viewers ignore the Name entry in a form dictionary. 4.9.3 Reference XObjects 56. Acrobat 8.0 and earlier viewers do not implement reference XObjects. The proxy is always used for viewing and printing. 5.2.5 Text Rendering Mode 57. In Acrobat 4.05 and earlier versions, text-showing operators such as Tj first perform the fills for all the glyphs in the string being shown, followed by the strokes for all the glyphs. This produces incorrect results if glyphs overlap. 5.3.2 Text-Showing Operators 58. In versions of Acrobat earlier than 3.0, the horizontal coordinate of the text position after the TJ operator paints a character glyph and moves by any specified offset must not be less than it was before the glyph was painted. 59. In Acrobat 4.0 and earlier viewers, position adjustments specified by numbers in a TJ array are performed incorrectly if the horizontal scaling parameter, Th, is different from its default value of 100. 5.5.1 Type 1 Fonts 60. All Acrobat viewers ignore the Name entry in a font dictionary. 61. Acrobat 5.0 and later viewers use the glyph widths stored in the font dictionary to override the widths of glyphs in the font program itself, which improves the consistency of the display and printing of the document. This addresses the situation in which the font program used by the conforming reader is different from the one used by the application that produced the document. The font program with the altered glyph widths may or may not be embedded. If it is embedded, its widths should exactly match the widths in the font dictionary. If the font program is not embedded, Acrobat overrides the widths in the font program on the conforming reader's system with the widths specified in the font dictionary. It is important that the widths in the font dictionary match the actual glyph widths of the font program that was used to produce the document. Consumers of PDF files depend on these widths in many different contexts, including viewing, printing, fauxing (font substitution), reflow, and word search.