Previews for \input insets.

Refactor code common to InsetInclude and InsetFormula into a new
PreviewedInset class.


git-svn-id: svn://svn.lyx.org/lyx/lyx-devel/trunk@4830 a592a061-630c-0410-9148-cb99ea01b6c8

src/graphics/ChangeLog

@@ -1,3 +1,18 @@
+2002-08-01  Angus Leeming  <leeming@lyx.org>
+
+	* PreviewedInset.[Ch]: new files. An abstract base class that can help
+	insets to generate previews.
+	The daughter class must instantiate three small methods.
+	The Inset would own an instance of this daughter class and invoke it
+	as necessary. For example, mathd/formula.C gets previews at the cost
+	of 15 or so lines of code.
+
+	* Makefile.am: add PreviewedInset.[Ch].
+
+	* PreviewLoader.C (add): add debug message.
+
+	* Previews.C (generateBufferPreviews): remove if-block from loop.
+
 2002-07-29  Lars Gullik Bjønnes  <larsbj@gullik.net>
 
 	* PreviewLoader.C (setFontScalingFactor): strip,frontStrip ->

src/graphics/Makefile.am

@@ -31,5 +31,7 @@ libgraphics_la_SOURCES = \
 	PreviewLoader.h \
 	PreviewLoader.C \
 	Previews.h \
-	Previews.C
+	Previews.C \
+	PreviewedInset.h \
+	PreviewedInset.C
 

src/graphics/PreviewLoader.C

@@ -383,6 +383,8 @@ void PreviewLoader::Impl::add(string const & latex_snippet)
 	if (!pconverter_ || status(latex_snippet) != NotFound)
 		return;
 
+	lyxerr[Debug::GRAPHICS] << "adding snippet:\n" << latex_snippet << endl;
+
 	pending_.push_back(latex_snippet);
 }
 

src/graphics/PreviewedInset.C

@@ -0,0 +1,106 @@
+// -*- C++ -*-
+/**
+ *  \file PreviewedInset.C
+ *  Copyright 2002 the LyX Team
+ *  Read the file COPYING
+ *
+ * \author Angus Leeming <leeming@lyx.org>
+ */
+
+#ifdef __GNUG__
+#pragma implementation
+#endif
+
+#include <config.h>
+
+#include "PreviewedInset.h"
+
+#include "BufferView.h"
+
+#include "GraphicsImage.h"
+#include "PreviewLoader.h"
+#include "PreviewImage.h"
+#include "Previews.h"
+
+#include <boost/bind.hpp>
+
+
+namespace grfx {
+
+bool PreviewedInset::activated()
+{
+	return Previews::activated();
+}
+
+
+void PreviewedInset::generatePreview() const
+{
+	if (!Previews::activated() || !previewWanted() ||
+	    !view() || !view()->buffer())
+		return;
+
+	grfx::Previews & previews = grfx::Previews::get();
+	grfx::PreviewLoader & loader = previews.loader(view()->buffer());
+	addPreview(loader);
+	loader.startLoading();
+}
+
+
+void PreviewedInset::addPreview(grfx::PreviewLoader & ploader) const
+{
+	if (!Previews::activated() || !previewWanted())
+		return;
+
+	// Generate the LaTeX snippet.
+	string const snippet = latexString();
+
+	pimage_ = ploader.preview(snippet);
+	if (pimage_)
+		return;
+
+	// If this is the first time of calling, connect to the
+	// grfx::PreviewLoader signal that'll inform us when the preview image
+	// is ready for loading.
+	if (!connection_.connected()) {
+		connection_ = ploader.connect(
+			boost::bind(&PreviewedInset::imageReady, this, _1));
+	}
+
+	ploader.add(snippet);
+}
+
+
+bool PreviewedInset::previewReady() const
+{
+	if (!grfx::Previews::activated() || !previewWanted() ||
+	    !view() || !view()->buffer())
+		return false;
+
+	// If the cached grfx::PreviewImage is invalid, update it.
+	string const snippet = latexString();
+
+	if (!pimage_ || snippet != pimage_->snippet()) {
+		grfx::PreviewLoader & ploader =
+			grfx::Previews::get().loader(view()->buffer());
+		pimage_ = ploader.preview(snippet);
+	}
+
+	if (!pimage_)
+		return false;
+
+	return pimage_->image(inset_, *view());
+}
+
+
+void PreviewedInset::imageReady(grfx::PreviewImage const & pimage) const
+{
+	// Check snippet against the Inset's current contents
+	if (latexString() != pimage.snippet())
+		return;
+
+	pimage_ = &pimage;
+	if (view())
+		view()->updateInset(&inset_, false);
+}
+
+} // namespace grfx

src/graphics/PreviewedInset.h

@@ -0,0 +1,85 @@
+// -*- C++ -*-
+/**
+ *  \file PreviewedInset.h
+ *  Copyright 2002 the LyX Team
+ *  Read the file COPYING
+ *
+ * \author Angus Leeming <leeming@lyx.org>
+ *
+ *  grfx::PreviewedInset is an abstract base class that can help insets to
+ *  generate previews. The daughter class must instantiate three small
+ *  methods. The Inset would own an instance of this daughter class.
+ */
+
+#ifndef PREVIEWEDINSET_H
+#define PREVIEWEDINSET_H
+
+#ifdef __GNUG__
+#pragma interface
+#endif
+
+#include "LString.h"
+#include <boost/signals/trackable.hpp>
+#include <boost/signals/connection.hpp>
+
+class Inset;
+class BufferView;
+
+namespace grfx {
+
+class PreviewImage;
+class PreviewLoader;
+
+class PreviewedInset : public boost::signals::trackable {
+public:
+	/// a wrapper for Previews::activated()
+	static bool activated();
+
+	///
+	PreviewedInset(Inset & inset) : inset_(inset), pimage_(0) {}
+
+	/** Find the PreviewLoader, add a LaTeX snippet to it and
+	 *  start the loading process.
+	 */
+	void generatePreview() const;
+
+	/** Add a LaTeX snippet to the PreviewLoader but do not start the
+	 *  loading process.
+	 */
+	void addPreview(PreviewLoader & ploader) const;
+
+	/// The preview has been generated and is ready to use.
+	bool previewReady() const;
+
+	/// If !previewReady() returns 0.
+	PreviewImage const * pimage() const { return pimage_; }
+
+protected:
+	/// Allow the daughter classes to cast up to the parent inset.
+	Inset * inset() const { return &inset_; }
+
+private:
+	/** This method is connected to the grfx::PreviewLoader::imageReady
+	 *  signal.
+	 */
+	void imageReady(PreviewImage const &) const;
+
+	/// Does the owning inset want a preview?
+	virtual bool previewWanted() const = 0;
+	///
+	virtual BufferView * view() const = 0;
+	/// a wrapper to Inset::latex
+	virtual string const latexString() const = 0;
+
+	///
+	Inset & inset_;
+	/// We don't own this
+	mutable PreviewImage const * pimage_;
+	///
+	mutable boost::signals::connection connection_;
+};
+
+} // namespace grfx
+
+
+#endif // PREVIEWEDINSET_H

src/graphics/Previews.C

@@ -94,9 +94,7 @@ void Previews::generateBufferPreviews(Buffer const & buffer) const
 	Buffer::inset_iterator end = buffer.inset_const_iterator_end();
 
 	for (; it != end; ++it) {
-		if ((*it)->lyxCode() == Inset::MATH_CODE) {
-			(*it)->generatePreview(ploader);
-		}
+		(*it)->addPreview(ploader);
 	}
 
 	ploader.startLoading();

src/insets/ChangeLog

@@ -1,3 +1,12 @@
+2002-08-01  Angus Leeming  <leeming@lyx.org>
+
+	* inset.h (generatePreview): renamed as addPreview.
+	(generatePreview): new method. Allows code to be moved out of
+	math_nestinset.C and into the new PreviewedInset class.
+
+	* insetinclude.[Ch] (ascent, descent, width, draw, addPreview):
+	add previews to the inset when \input-ing LaTeX.
+
 2002-07-29  Lars Gullik Bjønnes  <larsbj@gullik.net>
 
 	* several files: strip,frontStrip -> trim,ltrim,rtrim

src/insets/inset.h

@@ -332,14 +332,20 @@ public:
 	virtual int latexTextWidth(BufferView *) const;
 
 	/** Adds a LaTeX snippet to the Preview Loader for transformation
-	 *  into a bitmap image. Also connects to PreviewLoader::imageReady
-	 *  so that the inset is informed when the image has been generated
-	 *  in order to initiate its loading into LyX.
+	 *  into a bitmap image. Does not start the laoding process.
 	 *
 	 *  Most insets have no interest in this capability, so the method
 	 *  defaults to empty.
 	 */
-	virtual void generatePreview(grfx::PreviewLoader &) const {}
+	virtual void addPreview(grfx::PreviewLoader &) const {}
+
+	/** Find the PreviewLoader, add a LaTeX snippet to it and
+	 *  start the loading process.
+	 *
+	 *  Most insets have no interest in this capability, so the method
+	 *  defaults to empty.
+	 */
+	virtual void generatePreview() const {}
 
 protected:
 	///

src/insets/insetinclude.C

@@ -15,11 +15,15 @@
 #include "gettext.h"
 
 #include "frontends/Dialogs.h"
+#include "frontends/Painter.h"
 
 #include "support/filetools.h"
 #include "support/FileInfo.h"
 #include "support/lstrings.h"
 
+#include "graphics/PreviewedInset.h"
+#include "graphics/PreviewImage.h"
+
 #include <cstdlib>
 
 
@@ -29,6 +33,26 @@ using std::vector;
 using std::pair;
 
 extern BufferList bufferlist;
+extern BufferView * current_view;
+
+class InsetInclude::PreviewImpl : public grfx::PreviewedInset {
+public:
+	///
+	PreviewImpl(InsetInclude & p) : PreviewedInset(p) {}
+
+	///
+	bool previewWanted() const;
+	///
+	string const latexString() const;
+
+	///
+	BufferView * view() const { return current_view; }
+	///
+	InsetInclude & parent() const {
+		return *static_cast<InsetInclude*>(inset());
+	}
+};
+
 
 namespace {
 
@@ -47,12 +71,14 @@ string const uniqueID()
 
 
 InsetInclude::InsetInclude(Params const & p)
-	: params_(p), include_label(uniqueID())
+	: params_(p), include_label(uniqueID()),
+	  preview_(new PreviewImpl(*this))
 {}
 
 
 InsetInclude::InsetInclude(InsetCommandParams const & p, Buffer const & b)
-	: include_label(uniqueID())
+	: include_label(uniqueID()),
+	  preview_(new PreviewImpl(*this))
 {
 	params_.cparams = p;
 	params_.masterFilename_ = b.fileName();
@@ -110,6 +136,9 @@ void InsetInclude::set(Params const & p)
 	}
 
 	params_.cparams.setCmdName(command);
+
+	if (grfx::PreviewedInset::activated() && params_.flag == INPUT)
+		preview_->generatePreview();
 }
 
 
@@ -445,3 +474,88 @@ vector<pair<string,string> > const InsetInclude::getKeys() const
 
 	return keys;
 }
+
+
+int InsetInclude::ascent(BufferView * bv, LyXFont const & font) const
+{
+	return preview_->previewReady() ?
+		preview_->pimage()->ascent() : InsetButton::ascent(bv, font);
+}
+
+
+int InsetInclude::descent(BufferView * bv, LyXFont const & font) const
+{
+	return preview_->previewReady() ?
+		preview_->pimage()->descent() : InsetButton::descent(bv, font);
+}
+
+
+int InsetInclude::width(BufferView * bv, LyXFont const & font) const
+{
+	return preview_->previewReady() ?
+		preview_->pimage()->width() : InsetButton::width(bv, font);
+}
+
+
+void InsetInclude::draw(BufferView * bv, LyXFont const & font, int y,
+			float & xx, bool b) const
+{
+	if (!preview_->previewReady()) {
+		InsetButton::draw(bv, font, y, xx, b);
+		return;
+	}
+
+	int const x = int(xx);
+	int const w = width(bv, font);
+	int const d = descent(bv, font);
+	int const a = ascent(bv, font);
+	int const h = a + d;
+
+	bv->painter().image(x, y - a, w, h,
+			    *(preview_->pimage()->image(*this, *bv)));
+
+	xx += w;
+}
+
+
+//
+// preview stuff
+//
+
+void InsetInclude::addPreview(grfx::PreviewLoader & ploader) const
+{
+	lyxerr << "InsetInclude::addPreview" << endl;
+	preview_->addPreview(ploader);
+}
+
+
+bool InsetInclude::PreviewImpl::previewWanted() const
+{
+	return parent().params_.flag == InsetInclude::INPUT;
+}
+
+
+string const InsetInclude::PreviewImpl::latexString() const
+{
+	if (!view() || !view()->buffer())
+		return string();
+
+	ostringstream os;
+	parent().latex(view()->buffer(), os, false, false);
+
+	// This fails if the file has a relative path.
+	// return os.str().c_str();
+
+	// I would /really/ like not to do this...
+	// HELP!
+	string command;
+	string file = rtrim(split(os.str().c_str(), command, '{'), "}");
+
+	if (!AbsolutePath(file))
+		file = MakeAbsPath(file, view()->buffer()->filePath());
+
+	ostringstream out;
+	out << command << '{' << file << '}' << endl;
+	
+	return out.str().c_str();
+}

src/insets/insetinclude.h

@@ -18,6 +18,7 @@
 #include "insetcommand.h"
 
 #include <boost/signals/signal0.hpp>
+#include <boost/scoped_ptr.hpp>
 
 class Buffer;
 struct LaTeXFeatures;
@@ -65,6 +66,15 @@ public:
 	///
 	~InsetInclude();
 
+	/// Override these InsetButton methods if Previewing
+	int ascent(BufferView *, LyXFont const &) const;
+	///
+	int descent(BufferView *, LyXFont const &) const;
+	///
+	int width(BufferView *, LyXFont const &) const;
+	///
+	void draw(BufferView *, LyXFont const &, int, float &, bool) const;
+
 	/// get the parameters
 	Params const & params(void) const;
 	/// set the parameters
@@ -117,6 +127,9 @@ public:
 	/// return true if the file is or got loaded.
 	bool loadIfNeeded() const;
 
+	///
+	void addPreview(grfx::PreviewLoader &) const;
+
 	/// hide a dialog if about
 	boost::signal0<void> hideDialog;
 private:
@@ -133,6 +146,12 @@ private:
 	Params params_;
 	/// holds the entity name that defines the file location (SGML)
 	string const include_label;
+
+	/// Use the Pimpl idiom to hide the internals of the previewer.
+	class PreviewImpl;
+	friend class PreviewImpl;
+	/// The pointer never changes although *preview_'s contents may.
+	boost::scoped_ptr<PreviewImpl> const preview_;
 };
 
 

src/mathed/ChangeLog

@@ -1,3 +1,13 @@
+2002-08-01  Angus Leeming  <leeming@lyx.org>
+
+	* formula.C: move code into the new PreviewedInset class.
+
+	* formula.[Ch] (generatePreview): renamed as addPreview.
+	(generatePreview): new method invoking PreviewedInset::generatePreview.
+
+	* math_nestinset.C (notifyCursorLeaves): simplify. Now just calls
+	Inset::generatePreview.
+
 2002-07-29  Lars Gullik Bjønnes  <larsbj@gullik.net>
 
 	* formula.C (localDispatch): strip,frontStrip -> trim,ltrim,rtrim

src/mathed/formula.C

@@ -47,16 +47,11 @@
 #include "frontends/LyXView.h"
 #include "frontends/Painter.h"
 
-#include "graphics/GraphicsImage.h"
-#include "graphics/PreviewLoader.h"
+#include "graphics/PreviewedInset.h"
 #include "graphics/PreviewImage.h"
-#include "graphics/Previews.h"
 
 #include <fstream>
-#include <boost/bind.hpp>
-#include <boost/signals/trackable.hpp>
-#include <boost/signals/connection.hpp>
-#include <boost/utility.hpp>
+
 
 using std::ostream;
 using std::ifstream;
@@ -67,30 +62,26 @@ using std::vector;
 using std::getline;
 
 
-struct InsetFormula::PreviewImpl : public boost::signals::trackable {
+class InsetFormula::PreviewImpl : public grfx::PreviewedInset {
+public:
 	///
-	PreviewImpl(InsetFormula & p) : parent_(p), pimage_(0) {}
+	PreviewImpl(InsetFormula & p) : PreviewedInset(p) {}
 
+private:
+	///
+	bool previewWanted() const;
 	///
-	void generatePreview(grfx::PreviewLoader & previewer);
-
-	/** This method is connected to the grfx::PreviewLoader::imageReady
-	 *  signal.
-	 */
-	void previewReady(grfx::PreviewImage const &);
-
-	/// A helper method.
 	string const latexString() const;
-
 	///
-	bool usePreview() const;
-
+	BufferView * view() const
+	{
+		return parent().view();
+	}
 	///
-	InsetFormula & parent_;
-	///
-	mutable grfx::PreviewImage const * pimage_;
-	///
-	boost::signals::connection connection_;
+	InsetFormula & parent() const
+	{
+		return *static_cast<InsetFormula*>(inset());
+	}
 };
 
 
@@ -216,7 +207,7 @@ void InsetFormula::draw(BufferView * bv, LyXFont const & font,
 {
 	// This initiates the loading of the preview, so should come
 	// before the metrics are computed.
-	bool const use_preview = preview_->usePreview();
+	bool const use_preview = preview_->previewReady();
 
 	int const x = int(xx);
 	int const w = width(bv, font);
@@ -228,7 +219,7 @@ void InsetFormula::draw(BufferView * bv, LyXFont const & font,
 
 	if (use_preview) {
 		pi.pain.image(x, y - a, w, h,
-			      *(preview_->pimage_->image(*this, *bv)));
+			      *(preview_->pimage()->image(*this, *bv)));
 	} else {
 		//pi.base.style = display() ? LM_ST_DISPLAY : LM_ST_TEXT;
 		pi.base.style = LM_ST_TEXT;
@@ -441,17 +432,17 @@ bool InsetFormula::insetAllowed(Inset::Code code) const
 
 int InsetFormula::ascent(BufferView *, LyXFont const &) const
 {
-	return preview_->usePreview() ?
-		preview_->pimage_->ascent() : 1 + par_->ascent();
+	return preview_->previewReady() ?
+		preview_->pimage()->ascent() : 1 + par_->ascent();
 }
 
 
 int InsetFormula::descent(BufferView *, LyXFont const &) const
 {
-	if (!preview_->usePreview())
+	if (!preview_->previewReady())
 		return 1 + par_->descent();
 
-	int const descent = preview_->pimage_->descent();
+	int const descent = preview_->pimage()->descent();
 	return display() ? descent + 12 : descent;
 }
 
@@ -459,8 +450,8 @@ int InsetFormula::descent(BufferView *, LyXFont const &) const
 int InsetFormula::width(BufferView * bv, LyXFont const & font) const
 {
 	metrics(bv, font);
-	return preview_->usePreview() ?
-		preview_->pimage_->width() : par_->width();
+	return preview_->previewReady() ?
+		preview_->pimage()->width() : par_->width();
 }
 
 
@@ -480,58 +471,21 @@ void InsetFormula::mutate(string const & type)
 // preview stuff
 //
 
-void InsetFormula::generatePreview(grfx::PreviewLoader & ploader) const
+void InsetFormula::addPreview(grfx::PreviewLoader & ploader) const
 {
-	// Do nothing if no preview is desired.
-	if (!grfx::Previews::activated())
-		return;
-
-	preview_->generatePreview(ploader);
+	preview_->addPreview(ploader);
 }
 
 
-void InsetFormula::PreviewImpl::generatePreview(grfx::PreviewLoader & ploader)
+void InsetFormula::generatePreview() const
 {
-	// Generate the LaTeX snippet.
-	string const snippet = latexString();
-
-	pimage_ = ploader.preview(snippet);
-	if (pimage_)
-		return;
-
-	// If this is the first time of calling, connect to the
-	// grfx::PreviewLoader signal that'll inform us when the preview image
-	// is ready for loading.
-	if (!connection_.connected()) {
-		connection_ = ploader.connect(
-			boost::bind(&PreviewImpl::previewReady, this, _1));
-	}
-
-	ploader.add(snippet);
+	preview_->generatePreview();
 }
 
 
-bool InsetFormula::PreviewImpl::usePreview() const
+bool InsetFormula::PreviewImpl::previewWanted() const
 {
-	BufferView * view = parent_.view();
-
-	if (!grfx::Previews::activated() ||
-	    parent_.par_->asNestInset()->editing() ||
-	    !view || !view->buffer())
-		return false;
-
-	// If the cached grfx::PreviewImage is invalid, update it.
-	string const snippet = latexString();
-	if (!pimage_ || snippet != pimage_->snippet()) {
-		grfx::PreviewLoader & ploader =
-			grfx::Previews::get().loader(view->buffer());
-		pimage_ = ploader.preview(snippet);
-	}
-
-	if (!pimage_)
-		return false;
-
-	return pimage_->image(parent_, *view);
+	return !parent().par_->asNestInset()->editing();
 }
 
 
@@ -539,19 +493,6 @@ string const InsetFormula::PreviewImpl::latexString() const
 {
 	ostringstream ls;
 	WriteStream wi(ls, false, false);
-	parent_.par_->write(wi);
+	parent().par_->write(wi);
 	return ls.str().c_str();
 }
-
-
-void InsetFormula::PreviewImpl::previewReady(grfx::PreviewImage const & pimage)
-{
-	// Check snippet against the Inset's current contents
-	if (latexString() != pimage.snippet())
-		return;
-
-	pimage_ = &pimage;
-	BufferView * view = parent_.view();
-	if (view)
-		view->updateInset(&parent_, false);
-}

src/mathed/formula.h

@@ -82,7 +82,9 @@ public:
 	///
 	MathAtom & par() { return par_; }
 	///
-	void generatePreview(grfx::PreviewLoader &) const;
+	void generatePreview() const;
+	///
+	void addPreview(grfx::PreviewLoader &) const;
 	///
 	void mutate(string const & type);
 

src/mathed/math_nestinset.C

@@ -6,11 +6,8 @@
 #include "math_cursor.h"
 #include "math_mathmlstream.h"
 #include "formulabase.h"
-#include "BufferView.h"
 #include "debug.h"
 #include "frontends/Painter.h"
-#include "graphics/PreviewLoader.h"
-#include "graphics/Previews.h"
 
 using std::vector;
 
@@ -323,22 +320,10 @@ void MathNestInset::normalize(NormalStream & os) const
 
 void MathNestInset::notifyCursorLeaves()
 {
-	// Generate a preview only if previews are active and we are leaving
-	// the InsetFormula itself
-	if (!grfx::Previews::activated() ||
-	    !mathcursor || mathcursor->depth() != 1)
+	// Generate a preview only if we are leaving the InsetFormula itself
+	if (!mathcursor || mathcursor->depth() != 1)
 		return;
 
 	InsetFormulaBase * inset = mathcursor->formula();
-	BufferView * bufferview = inset->view();
-
-	// Paranoia check
-	if (!bufferview || !bufferview->buffer())
-		return;
-
-	grfx::Previews & previews = grfx::Previews::get();
-	grfx::PreviewLoader & loader = previews.loader(bufferview->buffer());
-
-	inset->generatePreview(loader);
-	loader.startLoading();
+	inset->generatePreview();
 }