From 0bb378ba6a5468f255a8c49c2fd714ecdf511c7d Mon Sep 17 00:00:00 2001
From: Kornel Benko <kornel@lyx.org>
Date: Thu, 9 Apr 2015 16:29:59 +0200
Subject: [PATCH] Adapt creation of preview images to the defaul document
 output.

Sometimes, even compilable documents could not display preview
snippets. Previously the preview was computed only with help
of latex or xelatex.
This also fixes #9371
---
 src/graphics/PreviewLoader.cpp | 57 +++++++++++++++++++++++++---------
 1 file changed, 43 insertions(+), 14 deletions(-)

diff --git a/src/graphics/PreviewLoader.cpp b/src/graphics/PreviewLoader.cpp
index 91834d2de4..addc6af224 100644
--- a/src/graphics/PreviewLoader.cpp
+++ b/src/graphics/PreviewLoader.cpp
@@ -218,7 +218,7 @@ private:
 	/// Called by the ForkedCall process that generated the bitmap files.
 	void finishedGenerating(pid_t, int);
 	///
-	void dumpPreamble(otexstream &) const;
+	void dumpPreamble(otexstream &, OutputParams::FLAVOR) const;
 	///
 	void dumpData(odocstream &, BitmapFile const &) const;
 
@@ -568,9 +568,44 @@ void PreviewLoader::Impl::startLoading(bool wait)
 		return;
 	}
 	of << "\\batchmode\n";
-	dumpPreamble(os);
+
+	LYXERR(Debug::LATEX, "Format = " << buffer_.params().getDefaultOutputFormat());
+	string latexparam = "";
+	OutputParams::FLAVOR flavor = buffer_.params().getOutputFlavor();
+	if (buffer_.params().encoding().package() == Encoding::japanese) {
+		latexparam = " --latex=platex";
+		flavor = OutputParams::LATEX;
+	}
+	else if (buffer_.params().useNonTeXFonts) {
+		if (flavor == OutputParams::LUATEX)
+			latexparam = " --latex=lualatex";
+		else {
+			flavor = OutputParams::XETEX;
+			latexparam = " --latex=xelatex";
+		}
+	}
+	else {
+		switch (flavor) {
+			case OutputParams::PDFLATEX:
+				latexparam = " --latex=pdflatex";
+				break;
+			case OutputParams::XETEX:
+				latexparam = " --latex=xelatex";
+				break;
+			case OutputParams::LUATEX:
+				latexparam = " --latex=lualatex";
+				break;
+			case OutputParams::DVILUATEX:
+				latexparam = " --latex=dvilualatex";
+				break;
+			default:
+				flavor = OutputParams::LATEX;
+		}
+	}
+	dumpPreamble(os, flavor);
 	// handle inputenc etc.
-	buffer_.params().writeEncodingPreamble(os, features);
+	// I think, this is already hadled by dumpPreamble(): Kornel
+	// buffer_.params().writeEncodingPreamble(os, features);
 	of << "\n\\begin{document}\n";
 	dumpData(of, inprogress.snippets);
 	of << "\n\\end{document}\n";
@@ -582,7 +617,7 @@ void PreviewLoader::Impl::startLoading(bool wait)
 	}
 
 	double const font_scaling_factor = buffer_.fontScalingFactor();
-	
+
 	// The conversion command.
 	ostringstream cs;
 	cs << pconverter_->command()
@@ -598,11 +633,7 @@ void PreviewLoader::Impl::startLoading(bool wait)
 		   << " --bg " << theApp()->hexName(bg);
 	}
 
-	// FIXME what about LuaTeX?
-	if (buffer_.params().useNonTeXFonts)
-		cs << " --latex=xelatex";
-	if (buffer_.params().encoding().package() == Encoding::japanese)
-		cs << " --latex=platex";
+	cs << latexparam;
 	if (buffer_.params().bibtex_command != "default")
 		cs << " --bibtex=" << quoteName(buffer_.params().bibtex_command);
 	else if (buffer_.params().encoding().package() == Encoding::japanese)
@@ -712,14 +743,12 @@ void PreviewLoader::Impl::finishedGenerating(pid_t pid, int retval)
 }
 
 
-void PreviewLoader::Impl::dumpPreamble(otexstream & os) const
+void PreviewLoader::Impl::dumpPreamble(otexstream & os, OutputParams::FLAVOR flavor) const
 {
 	// Dump the preamble only.
+	LYXERR(Debug::LATEX, "dumpPreamble, flavor == " << flavor);
 	OutputParams runparams(&buffer_.params().encoding());
-	if (buffer_.params().useNonTeXFonts)
-		runparams.flavor = OutputParams::XETEX;
-	else
-		runparams.flavor = OutputParams::LATEX;
+	runparams.flavor = flavor;
 	runparams.nice = true;
 	runparams.moving_arg = true;
 	runparams.free_spacing = true;
-- 
2.39.2