add billboard model type

panda/src/egg2pg/eggLoader.cxx

@@ -1981,6 +1981,12 @@ do_expand_object_type(EggGroup *egg_group, const pset<string> &expanded,
     } else if (cmp_nocase_uh(object_type, "decal") == 0) {
       egg_syntax = "<Decal> { 1 }";
       
+    } else if (cmp_nocase_uh(object_type, "billboard") == 0) {
+      egg_syntax = "<Billboard> { axis }";
+      
+    } else if (cmp_nocase_uh(object_type, "billboard-point") == 0) {
+      egg_syntax = "<Billboard> { point }";
+      
     } else if (cmp_nocase_uh(object_type, "backstage") == 0) {
       // Ignore "backstage" geometry.
       return false;