add valid flag, expand clear()

WFObj.cc

@@ -97,6 +97,8 @@ WFObj::WFObj(loadfile_t lf, loadtexture_t lt)
     {
         m_loadfile = loadfile;
     }
+    m_valid = false;
+    clear();
 }
 
 WFObj::~WFObj()
@@ -107,6 +109,10 @@ void WFObj::clear()
 {
     for (int i = 0; i < sizeof(m_vertices)/sizeof(m_vertices[0]); i++)
         m_vertices[i].clear();
+    m_faces.clear();
+    m_valid = false;
+    m_path = "";
+    m_current_material_name = "";
 }
 
 bool WFObj::load(const char *fname)

WFObj.h

@@ -79,6 +79,7 @@ protected:
     loadfile_t m_loadfile;
     loadtexture_t m_loadtexture;
     std::string m_current_material_name;
+    bool m_valid;
 };
 
 #endif