latex, allow image dimensions using px unit (96px=1in)

New key ``'pixelsize'`` in ``latex_elements`` dictionary.

CHANGES

@@ -46,6 +46,7 @@ Features added
 * latex, captions for literal blocks inside tables are handled, and long code
   lines wrapped to fit table cell (ref: #2704)
 * #2597: Show warning messages as darkred
+* latex, allow image dimensions using px unit (default is 96px=1in)
 
 Bugs fixed
 ----------

doc/config.rst

@@ -1601,6 +1601,14 @@ These options influence LaTeX output. See further :doc:`latex`.
      ``'pointsize'``
         Point size option of the document class (``'10pt'``, ``'11pt'`` or
         ``'12pt'``), default ``'10pt'``.
+     ``'pixelsize'``
+        px unit size, default ``'49336sp'`` which achieves ``96px=1in`` (as
+        ``1in = 72.27*65536 = 4736286.72sp``, and all dimensions in TeX are
+        internally integer multiples of ``sp``). To obtain for example
+        ``100px=1in``, one can use ``'0.01in'`` but it is more precise to issue
+        ``'pixelsize':'47363sp',``.
+
+        .. versionadded:: 1.5
      ``'babel'``
         "babel" package inclusion, default ``'\\usepackage{babel}'``.
      ``'fontpkg'``

sphinx/writers/latex.py

@@ -35,6 +35,9 @@ HEADER = r'''%% Generated by Sphinx.
 \def\sphinxdocclass{%(docclass)s}
 \newif\ifsphinxKeepOldNames %(keepoldnames)s
 \documentclass[%(papersize)s,%(pointsize)s%(classoptions)s]{%(wrapperclass)s}
+\ifdefined\pdfpxdimen
+   \let\sphinxpxdimen\pdfpxdimen\else\newdimen\sphinxpxdimen
+\fi \sphinxpxdimen=%(pixelsize)s\relax
 \usepackage{iftex}
 %(passoptionstopackages)s
 %(inputenc)s
@@ -299,6 +302,7 @@ class LaTeXTranslator(nodes.NodeVisitor):
     default_elements = {
         'papersize':       'letterpaper',
         'pointsize':       '10pt',
+        'pixelsize':       '49336sp',
         'classoptions':    '',
         'extraclassoptions': '',
         'passoptionstopackages': '',
@@ -1380,9 +1384,10 @@ class LaTeXTranslator(nodes.NodeVisitor):
             return width_str
         res = width_str
         amount, unit = match.groups()[:2]
-        if not unit or unit == "px":
-            # pixels: let LaTeX alone
+        if not unit:
             return None
+        elif unit == "px":
+            res = "%.3f\\sphinxpxdimen" % (float(amount))
         elif unit == "%":
             res = "%.3f\\linewidth" % (float(amount) / 100.0)
         return res