From 0fb63fb10ee905de33fb5217cb8954446dbfebc1 Mon Sep 17 00:00:00 2001
From: Richard Heck <rgheck@comcast.net>
Date: Mon, 9 Nov 2009 00:55:37 +0000
Subject: [PATCH] Just some style, and some comments, as I try to figure this
 out.

git-svn-id: svn://svn.lyx.org/lyx/lyx-devel/trunk@31910 a592a061-630c-0410-9148-cb99ea01b6c8
---
 src/Converter.cpp | 10 +++++++---
 src/Graph.cpp     | 29 +++++++++++++++--------------
 src/Graph.h       | 27 ++++++++++++---------------
 3 files changed, 34 insertions(+), 32 deletions(-)

diff --git a/src/Converter.cpp b/src/Converter.cpp
index 9a849a4017..86ad195cba 100644
--- a/src/Converter.cpp
+++ b/src/Converter.cpp
@@ -635,13 +635,17 @@ bool Converters::runLaTeX(Buffer const & buffer, string const & command,
 
 void Converters::buildGraph()
 {
+	// clear graph's data structures
 	G_.init(formats.size());
 	ConverterList::iterator beg = converterlist_.begin();
 	ConverterList::iterator const end = converterlist_.end();
+	// each of the converters knows how to convert one format to another
+	// so, for each of them, we create an arrow on the graph, going from 
+	// the one to the other
 	for (ConverterList::iterator it = beg; it != end ; ++it) {
-		int const s = formats.getNumber(it->from);
-		int const t = formats.getNumber(it->to);
-		G_.addEdge(s,t);
+		int const from = formats.getNumber(it->from);
+		int const to   = formats.getNumber(it->to);
+		G_.addEdge(from, to);
 	}
 }
 
diff --git a/src/Graph.cpp b/src/Graph.cpp
index 379ec2966c..81883ae31e 100644
--- a/src/Graph.cpp
+++ b/src/Graph.cpp
@@ -107,8 +107,7 @@ bool Graph::isReachable(int from, int to)
 	if (from == to)
 		return true;
 
-	int const s = bfs_init(from);
-	if (s < 0 || to < 0)
+	if (to < 0 || bfs_init(from) < 0)
 		return false;
 
 	while (!Q_.empty()) {
@@ -133,15 +132,14 @@ bool Graph::isReachable(int from, int to)
 }
 
 
-Graph::EdgePath const
-Graph::getPath(int from, int t)
+Graph::EdgePath const Graph::getPath(int from, int to)
 {
 	EdgePath path;
-	if (from == t)
+	if (from == to)
 		return path;
 
 	int const s = bfs_init(from);
-	if (s < 0 || t < 0)
+	if (s < 0 || to < 0)
 		return path;
 
 	vector<int> prev_edge(formats.size());
@@ -151,7 +149,7 @@ Graph::getPath(int from, int t)
 	while (!Q_.empty()) {
 		int const i = Q_.front();
 		Q_.pop();
-		if (i == t) {
+		if (i == to) {
 			found = true;
 			break;
 		}
@@ -174,14 +172,15 @@ Graph::getPath(int from, int t)
 	if (!found)
 		return path;
 
-	while (t != s) {
-		path.push_back(prev_edge[t]);
-		t = prev_vertex[t];
+	while (to != s) {
+		path.push_back(prev_edge[to]);
+		to = prev_vertex[to];
 	}
 	reverse(path.begin(), path.end());
 	return path;
 }
 
+
 void Graph::init(int size)
 {
 	vertices_ = vector<Vertex>(size);
@@ -189,13 +188,15 @@ void Graph::init(int size)
 	numedges_ = 0;
 }
 
-void Graph::addEdge(int s, int t)
+
+void Graph::addEdge(int from, int to)
 {
-	vertices_[t].in_vertices.push_back(s);
-	vertices_[s].out_vertices.push_back(t);
-	vertices_[s].out_edges.push_back(numedges_++);
+	vertices_[to].in_vertices.push_back(from);
+	vertices_[from].out_vertices.push_back(to);
+	vertices_[from].out_edges.push_back(numedges_++);
 }
 
+
 vector<Graph::Vertex> Graph::vertices_;
 
 
diff --git a/src/Graph.h b/src/Graph.h
index f2296b85a9..3955c3e60c 100644
--- a/src/Graph.h
+++ b/src/Graph.h
@@ -24,20 +24,18 @@ public:
 	Graph() : numedges_(0) {};
 	///
 	typedef std::vector<int> EdgePath;
-	///
-	std::vector<int> const
-	getReachableTo(int, bool clear_visited);
-	///
+	/// \return a vector of the vertices from which "to" can be reached
+	std::vector<int> const getReachableTo(int to, bool clear_visited);
+	/// \return a vector of the vertices that can be reached from "from"
 	std::vector<int> const
-	getReachable(int, bool only_viewable,
-		     bool clear_visited);
-	///
-	bool isReachable(int, int);
-	///
-	EdgePath const getPath(int, int);
-	///
-	void addEdge(int s, int t);
-	///
+		getReachable(int from, bool only_viewable, bool clear_visited);
+	/// Can "from" be reached from "to"?
+	bool isReachable(int from, int to);
+	/// Find a path from "from" to "to".
+	EdgePath const getPath(int from, int to);
+	/// Called repeatedly to build the graph.
+	void addEdge(int from, int to);
+	/// Reset the internal data structures.
 	void init(int size);
 
 private:
@@ -52,8 +50,7 @@ private:
 		std::vector<int> out_edges;
 	};
 	///
-	static
-	std::vector<Vertex> vertices_;
+	static std::vector<Vertex> vertices_;
 	///
 	std::vector<bool> visited_;
 	///
-- 
2.39.2