bind texture when switching material

src/Engine_Object.cc

@@ -552,6 +552,7 @@ void Engine::Object::draw()
                 WFObj::Material & m = it->second;
                 if (m.flags & WFObj::Material::TEXTURE_BIT)
                 {
+                    glBindTexture(GL_TEXTURE_2D, m.texture);
                     if (program != m_engine.m_programs[PROG_OBJ_TEX])
                     {
                         program = m_engine.m_programs[PROG_OBJ_TEX];