bring back the triangle

panda/src/testbed/pview.cxx

@@ -30,7 +30,12 @@ main(int argc, char *argv[]) {
 
     window->enable_keyboard();
     window->setup_trackball();
-    window->load_models(window->get_render(), argc, argv);
+    if (argc < 2) {
+      // If we have no arguments, get that trusty old triangle out.
+      window->load_default_model(window->get_render());
+    } else {
+      window->load_models(window->get_render(), argc, argv);
+    }
     window->loop_animations();
 
     framework.enable_default_keys();