diff --git a/src/Nazara/3D/Loaders/OBJ/Loader.cpp b/src/Nazara/3D/Loaders/OBJ/Loader.cpp
index 1754bf40e..0d295c795 100644
--- a/src/Nazara/3D/Loaders/OBJ/Loader.cpp
+++ b/src/Nazara/3D/Loaders/OBJ/Loader.cpp
@@ -184,13 +184,13 @@ namespace
 		NzString mtlLib = parser.GetMtlLib();
 		if (parameters.loadMaterials && !mtlLib.IsEmpty())
 		{
-			NzString baseDir = stream.GetDirectory();
-			NzFile file(baseDir + mtlLib);
+			NzFile file(stream.GetDirectory() + mtlLib);
 			if (file.Open(NzFile::ReadOnly | NzFile::Text))
 			{
 				NzMTLParser materialParser(file);
 				if (materialParser.Parse())
 				{
+					NzString baseDir = file.GetDirectory();
 					for (unsigned int i = 0; i < meshCount; ++i)
 					{
 						const NzString& matName = materials[meshes[i].material];
diff --git a/src/Nazara/3D/Loaders/OBJ/OBJParser.cpp b/src/Nazara/3D/Loaders/OBJ/OBJParser.cpp
index 90a3f55df..b0f5b749c 100644
--- a/src/Nazara/3D/Loaders/OBJ/OBJParser.cpp
+++ b/src/Nazara/3D/Loaders/OBJ/OBJParser.cpp
@@ -170,23 +170,65 @@ bool NzOBJParser::Parse()
 						break;
 					}
 
-					pos += offset;
+					if (p < 0)
+					{
+						p += m_positions.size() + 1;
+						if (p < 0)
+						{
+							Error("Vertex index out of range (" + NzString::Number(p) + " < 0");
+							error = true;
+							break;
+						}
+					}
+					else
+						p--;
+
+					if (n < 0)
+					{
+						n += m_normals.size() + 1;
+						if (n < 0)
+						{
+							Error("Vertex index out of range (" + NzString::Number(n) + " < 0");
+							error = true;
+							break;
+						}
+					}
+					else
+						n--;
+
+					if (t < 0)
+					{
+						t += m_texCoords.size() + 1;
+						if (t < 0)
+						{
+							Error("Vertex index out of range (" + NzString::Number(t) + " < 0");
+							error = true;
+							break;
+						}
+					}
+					else
+						t--;
 
 					if (static_cast<unsigned int>(p) >= m_positions.size())
 					{
-						Error("Vertex index out of range " + NzString::Number(p) + " > " + NzString::Number(m_positions.size()));
+						Error("Vertex index out of range (" + NzString::Number(p) + " >= " + NzString::Number(m_positions.size()) + ')');
+						error = true;
 						break;
 					}
 					else if (n >= 0 && static_cast<unsigned int>(n) >= m_normals.size())
 					{
-						Error("Normal index out of range " + NzString::Number(n) + " > " + NzString::Number(m_normals.size()));
+						Error("Normal index out of range (" + NzString::Number(n) + " >= " + NzString::Number(m_normals.size()) + ')');
+						error = true;
 						break;
 					}
 					else if (t >= 0 && static_cast<unsigned int>(t) >= m_texCoords.size())
 					{
-						Error("TexCoord index out of range " + NzString::Number(t) + " > " + NzString::Number(m_texCoords.size()));
+						Error("TexCoord index out of range (" + NzString::Number(t) + " >= " + NzString::Number(m_texCoords.size()) + ')');
+						error = true;
 						break;
 					}
+
+					pos += offset;
 				}
 
 				if (!error)
@@ -234,7 +276,7 @@ bool NzOBJParser::Parse()
 				if (m_currentLine[1] == ' ')
 				{
 					NzString param = m_currentLine.Substr(2);
-					if (param != '0' && param != '1' && param != "on" && param != "off")
+					if (param != "all" && param != "on" && param != "off" && !param.IsNumber())
 						UnrecognizedLine();
 				}
 				else
@@ -339,6 +381,12 @@ bool NzOBJParser::Parse()
 		}
 	}
 
+	if (m_meshes.empty())
+	{
+		NazaraError("No meshes");
+		return false;
+	}
+
 	m_materials.resize(matCount);
 	for (auto it : materials)
 		m_materials[it.second] = it.first;