diff --git a/TileGenerator.cpp b/TileGenerator.cpp
index f0ae648..4617aea 100644
--- a/TileGenerator.cpp
+++ b/TileGenerator.cpp
@@ -9,6 +9,7 @@
 
 #include <cstdio>
 #include <cstdlib>
+#include <climits>
 #include <fstream>
 #include <gdfontmb.h>
 #include <iostream>
@@ -66,7 +67,9 @@ static inline int readBlockContent(const unsigned char *mapData, int version, in
 		}
 	}
 	else {
-		throw VersionError();
+		std::ostringstream oss;
+		oss << "Unsupported map version " << version;
+		throw std::runtime_error(oss.str());
 	}
 }
 
@@ -91,13 +94,14 @@ TileGenerator::TileGenerator():
 	m_drawOrigin(false),
 	m_drawPlayers(false),
 	m_drawScale(false),
+	m_shading(true),
 	m_border(0),
 	m_db(0),
 	m_image(0),
-	m_xMin(0),
-	m_xMax(0),
-	m_zMin(0),
-	m_zMax(0),
+	m_xMin(INT_MAX),
+	m_xMax(INT_MIN),
+	m_zMin(INT_MAX),
+	m_zMax(INT_MIN),
 	m_geomX(-50),
 	m_geomY(-50),
 	m_geomX2(50),
@@ -140,10 +144,10 @@ Color TileGenerator::parseColor(const std::string &color)
 {
 	Color parsed;
 	if (color.length() != 7) {
-		throw ColorError();
+		throw std::runtime_error("Color not 7 characters long");
 	}
 	if (color[0] != '#') {
-		throw ColorError();
+		throw std::runtime_error("Color does not begin with #");
 	}
 	long col = strtol(color.c_str() + 1, NULL, 16);
 	parsed.b = col % 256;
@@ -172,6 +176,11 @@ void TileGenerator::setDrawScale(bool drawScale)
 	}
 }
 
+void TileGenerator::setShading(bool shading)
+{
+	m_shading = shading;
+}
+
 void TileGenerator::setGeometry(int x, int y, int w, int h)
 {
 	if (x > 0) {
@@ -268,8 +277,7 @@ void TileGenerator::openDb(const std::string &input)
 {
 	string db_name = input + "map.sqlite";
 	if (sqlite3_open_v2(db_name.c_str(), &m_db, SQLITE_OPEN_READONLY | SQLITE_OPEN_PRIVATECACHE, 0) != SQLITE_OK) {
-		std::cerr << sqlite3_errmsg(m_db) << ", Database file: " << db_name << std::endl;
-		throw DbError();
+		throw std::runtime_error(std::string(sqlite3_errmsg(m_db)) + ", Database file: " + db_name);
 	}
 }
 
@@ -309,7 +317,7 @@ void TileGenerator::loadBlocks()
 		m_positions.unique();
 	}
 	else {
-		throw DbError();
+		throw std::runtime_error("Failed to get list of MapBlocks");
 	}
 }
 
@@ -339,7 +347,7 @@ void TileGenerator::renderMap()
 	sqlite3_stmt *statement;
 	string sql = "SELECT pos, data FROM blocks WHERE (pos >= ? AND pos <= ?)";
 	if (sqlite3_prepare_v2(m_db, sql.c_str(), sql.length(), &statement, 0) != SQLITE_OK) {
-		throw DbError();
+		throw std::runtime_error("Failed to get MapBlock");
 	}
 
 	std::list<int> zlist = getZValueList();
@@ -454,7 +462,8 @@ void TileGenerator::renderMap()
 				}
 			}
 		}
-		renderShading(zPos);
+		if(m_shading)
+			renderShading(zPos);
 	}
 }
 
diff --git a/TileGenerator.h b/TileGenerator.h
index a877eea..1a445e5 100644
--- a/TileGenerator.h
+++ b/TileGenerator.h
@@ -56,15 +56,6 @@ struct BlockPos {
 	}
 };
 
-class DbError {
-};
-
-class ColorError {
-};
-
-class VersionError {
-};
-
 
 class TileGenerator
 {
@@ -84,6 +75,7 @@ public:
 	void setDrawOrigin(bool drawOrigin);
 	void setDrawPlayers(bool drawPlayers);
 	void setDrawScale(bool drawScale);
+	void setShading(bool shading);
 	void setGeometry(int x, int y, int w, int h);
 	void parseColorsFile(const std::string &fileName);
 	void generate(const std::string &input, const std::string &output);
@@ -115,6 +107,7 @@ private:
 	bool m_drawOrigin;
 	bool m_drawPlayers;
 	bool m_drawScale;
+	bool m_shading;
 	int m_border;
 
 	sqlite3 *m_db;
diff --git a/mapper.cpp b/mapper.cpp
index 14c69fa..0d653a4 100644
--- a/mapper.cpp
+++ b/mapper.cpp
@@ -29,6 +29,7 @@ void usage()
 			"  --drawscale\n"
 			"  --drawplayers\n"
 			"  --draworigin\n"
+			"  --noshading\n"
 			"  --geometry x:y+w+h\n"
 			"Color format: '#000000'\n";
 	std::cout << usage_text;
@@ -48,6 +49,7 @@ int main(int argc, char *argv[])
 		{"draworigin", no_argument, 0, 'R'},
 		{"drawplayers", no_argument, 0, 'P'},
 		{"drawscale", no_argument, 0, 'S'},
+		{"noshading", no_argument, 0, 'H'},
 		{"geometry", required_argument, 0, 'g'},
 	};
 
@@ -63,14 +65,14 @@ int main(int argc, char *argv[])
 		if (c == -1) {
 			if (input.empty() || output.empty()) {
 				usage();
-				exit(-1);
+				return -1;
 			}
 			break;
 		}
 		switch (c) {
 			case 'h':
 				usage();
-				exit(0);
+				return 0;
 				break;
 			case 'i':
 				input = optarg;
@@ -99,6 +101,9 @@ int main(int argc, char *argv[])
 			case 'S':
 				generator.setDrawScale(true);
 				break;
+			case 'H':
+				generator.setShading(false);
+				break;
 			case 'g': {
 					istringstream geometry;
 					geometry.str(optarg);
@@ -116,5 +121,11 @@ int main(int argc, char *argv[])
 				abort();
 		}
 	}
-	generator.generate(input, output);
+	try {
+		generator.generate(input, output);
+	} catch(std::runtime_error e) {
+		std::cout<<"Exception: "<<e.what()<<std::endl;
+		return 1;
+	}
+	return 0;
 }