first shot at preview. It crashes. Don't know why. To see it work a bit, change

formula.C:191, to see it crash remove the comment further down.


git-svn-id: svn://svn.lyx.org/lyx/lyx-devel/trunk@4482 a592a061-630c-0410-9148-cb99ea01b6c8

src/mathed/formula.C

@@ -43,6 +43,8 @@
 #include "textpainter.h"
 #include "preview.h"
 
+#include "graphics/GraphicsCacheItem.h"
+
 using std::ostream;
 using std::ifstream;
 using std::istream;
@@ -190,8 +192,11 @@ void InsetFormula::draw(BufferView * bv, LyXFont const & font,
 	ostringstream os;
 	WriteStream wi(os, false, false);
 	par_->write(wi);
-	if (grfx::ImagePtr image = preview(os.str()))
+	if (preview(os.str(), preview_) && preview_.get()) {
-		pain.image(x, y, w, h, *image);
+		cerr << "image could be drawn\n";
+		// LyX crashes if we try that. Why? Andre'
+		//pi.pain.image(x, y, w, h, *(preview_->image()));
+	}
 #endif
 
 	xx += par_->width();

src/mathed/formula.h

@@ -24,6 +24,7 @@
 #include "formulabase.h"
 #include "math_defs.h"
 #include "math_atom.h"
+#include "graphics/GraphicsTypes.h"
 
 class MathHullInset;
 
@@ -89,7 +90,9 @@ private:
 	///
 	void handleExtern(string const & arg);
 
-	///
+	/// contents
 	MathAtom par_;
+	/// LaTeX preview
+	mutable grfx::GraphicPtr preview_;
 };
 #endif

src/mathed/preview.C

@@ -1,71 +1,63 @@
 #include <config.h>
 
-#include "formula.h"
 #include "debug.h"
-#include "frontends/Painter.h"
 #include "support/systemcall.h"
 #include "graphics/GraphicsTypes.h"
 #include "graphics/GraphicsImage.h"
-#include "graphics/GraphicsImageXPM.h"
-#include "graphics/GraphicsCacheItem.h"
 #include "graphics/GraphicsCache.h"
+#include "graphics/GraphicsCacheItem.h"
+#include "Lsstream.h"
 
 #include <fstream>
-#include <map>
 
+#include <boost/utility.hpp>
+#include <boost/bind.hpp>
 
 using namespace std;
 
 
-namespace {
+// built some unique filename
-
+string canonical_name(string const & str)
-	typedef map<string, grfx::ImagePtr> previews_map;
+{
-
+	ostringstream os;
-	// cache for computed previews
+	for (string::const_iterator it = str.begin(); it != str.end(); ++it) 
-	previews_map thePreviews;
+		os << char('A' + (*it & 15)) << char('a' + (*it >> 4));
-
+	return os.str();
-	// cache for scheduled previews
-	vector<string> theSchedule;
 }
 
 
-#if 0
+bool preview(string const & str, grfx::GraphicPtr & graphic)
-class PreviewCallbackLoaded {
-public:
-	///
-	PreviewCallbackLoaded(string const & filename)
-		: image_(grfx::GImageXPM::newImage())
-	{
-		lyxerr[Debug::GRAPHICS] << "Loading image." << endl;
-
-		grfx::GImage::SignalTypePtr s(new grfx::GImage::SignalType(&PreviewCallbackLoaded::imageLoaded));
-		image_->load(filename, s);
-	}
-
-	///
-	void imageLoaded(bool result)
-	{
-		lyxerr << "Image loaded with result: " << result << endl;
-	}
-
-	grfx::ImagePtr image_;
-
-};
-#endif
-
-
-grfx::ImagePtr preview(string const & str)
 {
-	// do we already have access to a rendered version?
+	string base = canonical_name(str);
-	previews_map::const_iterator it = thePreviews.find(str);
+	string dir  = "/tmp/lyx/";
-	if (it != thePreviews.end())
+	string file = dir + base + ".ps";
-		return it->second;
+	cerr << "writing '" << str << "' to '" << file << "'\n";
 
-	// constructing new item
+	// get the cache
-	//grfx::ImagePtr & im = thePreviews[str];
+	grfx::GCache & gc = grfx::GCache::get();
 
-	lyxerr << "writing: " << str << endl;
+	// look up the file
-	std::ofstream of("/tmp/previewlyx.tex");
+	if (gc.inCache(file)) {
+
+		// it's already in there. Get hold of it.
+		grfx::GraphicPtr gr = grfx::GraphicPtr(gc.graphic(file));
+
+		// is it already loaded?
+		if (gr->status() == grfx::Loaded) {
+			cerr << "file '" << file << "' ready for display\n";
+			cerr << "im: " << graphic.get() << " " << gr.get() << "\n";
+			graphic = gr;
+			return true;
+		}
+
+		// otherwise we have to wait again
+		cerr << "file '" << file << "' not finished loading\n";
+		return false;
+	}
+
+	// The real work starts.
+	string const texfile = dir + base + ".tex";
+	std::ofstream of(texfile.c_str());
 	of << "\\documentclass{article}"
 	   << "\\usepackage{amssymb}"
 	   << "\\thispagestyle{empty}"
@@ -74,58 +66,17 @@ grfx::ImagePtr preview(string const & str)
 	   << "\\end{document}\n";
 	of.close();
 
-	Systemcall sc1;
+	string const cmd =
-	sc1.startscript(Systemcall::Wait,
+		"latex " + base + ".tex ; dvips -o " + base + ".ps " + base + ".dvi ";
-		"(cd /tmp ; latex previewlyx.tex ; dvips previewlyx.dvi)");
+	//cerr << "calling: '" << "(cd " + dir + "; " + cmd + ")\n";
+	Systemcall sc;
+	sc.startscript(Systemcall::Wait, "(cd " + dir + "; " + cmd + ")");
 
-	Systemcall sc2;
+	// now we are done, add the file to the cache
-	sc2.startscript(Systemcall::Wait,
+	gc.add(file);
-		"(cd /tmp ; convert previewlyx.ps previewlyx.xpm)");
+	gc.graphic(file)->startLoading();
 
-	//PreviewCallbackLoaded cb("/tmp/previewlyx.xpm");
+	// This might take a while. Wait for the next round.
-
+	cerr << "file '" << file << "' registered\n";
-#if 0
+	return false;
-	//grfx::SignalLoadTypePtr on_finish;
-	//on_finish.reset(new SignalLoadType);
-	//on_finish->connect(SigC::slot(this, &imageLoaded));
-
-	// load image
-	XpmImage * xpm_image = new XpmImage;
-	int const success =
-		XpmReadFileToXpmImage("/tmp/previewlyx.ps", xpm_image, 0);
-
-	switch (success) {
-	case XpmOpenFailed:
-		lyxerr[Debug::GRAPHICS]
-			<< "No XPM image file found." << std::endl;
-		break;
-
-	case XpmFileInvalid:
-		lyxerr[Debug::GRAPHICS]
-			<< "File format is invalid" << std::endl;
-		break;
-
-	case XpmNoMemory:
-		lyxerr[Debug::GRAPHICS]
-			<< "Insufficient memory to read in XPM file"
-			<< std::endl;
-		break;
-	}
-
-	if (success != XpmSuccess) {
-		XpmFreeXpmImage(xpm_image);
-		delete xpm_image;
-
-		lyxerr[Debug::GRAPHICS]
-			<< "Error reading XPM file '"
-			<< XpmGetErrorString(success) << "'"
-			<< std::endl;
-	} else {
-		//grfx::GImageXPM * xim = static_cast<grfx::GImageXPM *>(im.get());
-		//xim->image_.reset(*xpm_image);
-	}
-
-	return im;
-#endif
-	return it->second;	
 }

src/mathed/preview.h

@@ -4,6 +4,6 @@
 #include "LString.h"
 #include "graphics/GraphicsTypes.h"
 
-grfx::ImagePtr preview(string const & str);
+bool preview(string const & str, grfx::GraphicPtr & graphic);
 
 #endif