added F5 reload script key which will re-load the current script and discover any newly added event handler functions

git-svn-id: svn://anubis/anaglym/trunk@168 99a6e188-d820-4881-8870-2d33a10e2619

.todo

@@ -1,2 +1 @@
 - add functions to draw 2d graphics (lines, rectangles)
-- add a reload engine key that will "import" the current script

Engine.cc

@@ -137,9 +137,10 @@ Engine::~Engine()
 bool Engine::load(const char * program)
 {
     m_program_path = program;
-    size_t pos = m_program_path.find_last_of("/\\");
-    m_program_path = (pos != string::npos)
-                        ? m_program_path.substr(0, pos)
+    m_program_directory = program;
+    size_t pos = m_program_directory.find_last_of("/\\");
+    m_program_directory = (pos != string::npos)
+                        ? m_program_directory.substr(0, pos)
                         : ".";
 
     string path = locateResource(FONT_NAME);
@@ -178,14 +179,7 @@ bool Engine::load(const char * program)
         return false;
     }
 
-    checkForFunction("init", init);
-    checkForFunction("update_event", update);
-    checkForFunction("update_overlay_event", update_overlay);
-    checkForFunction("key_down_event", key_down);
-    checkForFunction("key_up_event", key_up);
-    checkForFunction("mousebutton_down_event", mousebutton_down);
-    checkForFunction("mousebutton_up_event", mousebutton_up);
-    checkForFunction("mouse_motion_event", mouse_motion);
+    checkForAllHandlerFunctions();
 
     if (m_event_init_present)
     {
@@ -199,6 +193,18 @@ bool Engine::load(const char * program)
     return true;
 }
 
+void Engine::checkForAllHandlerFunctions()
+{
+    checkForFunction("init", init);
+    checkForFunction("update_event", update);
+    checkForFunction("update_overlay_event", update_overlay);
+    checkForFunction("key_down_event", key_down);
+    checkForFunction("key_up_event", key_up);
+    checkForFunction("mousebutton_down_event", mousebutton_down);
+    checkForFunction("mousebutton_up_event", mousebutton_up);
+    checkForFunction("mouse_motion_event", mouse_motion);
+}
+
 void Engine::reportErrors(int status)
 {
     if (status != 0)
@@ -230,7 +236,7 @@ string Engine::locateResource(const string & shortname)
     string try_path;
 
     /* look for the resource relative to the loaded script's directory */
-    try_path = m_program_path + "/" + shortname;
+    try_path = m_program_directory + "/" + shortname;
     if (fileExists(try_path))
         return try_path;
 
@@ -453,7 +459,15 @@ bool Engine::import(const char * name)
         string file_path = locateResource(nm + ".lua");
         if (file_path != "")
         {
-            int s = luaL_loadfile(m_luaState, file_path.c_str());
+            return importFullPath(file_path.c_str());
+        }
+    }
+    return false;
+}
+
+bool Engine::importFullPath(const char * path)
+{
+    int s = luaL_loadfile(m_luaState, path);
     if (s == 0)
     {
         s = lua_pcall(m_luaState, 0, 0, 0);
@@ -461,7 +475,9 @@ bool Engine::import(const char * name)
             return true;
         reportErrors(s);
     }
-        }
+    else
+    {
+        cerr << "Error " << s << " loading '" << path << "'" << endl;
     }
     return false;
 }
@@ -555,6 +571,9 @@ void Engine::run()
                                 ? SDL_GRAB_OFF
                                 : SDL_GRAB_ON);
                         break;
+                    case SDLK_F5:
+                        reloadProgram();
+                        break;
                     default:
                         key_down_event(event.key.keysym.sym);
                 }
@@ -729,6 +748,8 @@ void Engine::mouse_motion_event(int x, int y, int xrel, int yrel)
 void Engine::checkForFunctionFull(const std::string & lua_fn_name,
         const std::string & event_name, bool & presentFlag)
 {
+    if (!presentFlag)   /* only look for events we do not have a handler for */
+    {
         lua_getfield(m_luaState, LUA_GLOBALSINDEX, lua_fn_name.c_str());
         if (lua_isfunction(m_luaState, -1))
         {
@@ -741,6 +762,7 @@ void Engine::checkForFunctionFull(const std::string & lua_fn_name,
             lua_pop(m_luaState, 1);
             presentFlag = false;
         }
+    }
 }
 
 void Engine::doRegisterHandlerFull(int index,
@@ -751,6 +773,12 @@ void Engine::doRegisterHandlerFull(int index,
     presentFlag = true;
 }
 
+void Engine::reloadProgram()
+{
+    importFullPath(m_program_path.c_str());
+    checkForAllHandlerFunctions();
+}
+
 void Engine::doPhysics()
 {
     static Uint32 last_updated = 0;

Engine.h

@@ -133,6 +133,7 @@ class Engine
         bool isKeyDown(const std::string & key);
         void exit();
         bool import(const char * name);
+        bool importFullPath(const char * path);
         GLuint loadTexture(const char * name);
         void debug_hook(lua_Debug * debug);
         void getScreenSize(int * width, int * height);
@@ -164,12 +165,15 @@ class Engine
                 const std::string & event_name, bool & presentFlag);
         void doRegisterHandlerFull(int index,
                 const std::string & event_name, bool & presentFlag);
+        void reloadProgram();
+        void checkForAllHandlerFunctions();
 
         Video &         m_video;
         TextureCache    m_textureCache;
         EngineFileLoader * m_fileLoader;
         lua_State *     m_luaState;
         std::string     m_program_path;
+        std::string     m_program_directory;
         std::string     m_engine_path;
         OdeWorld        m_world;
         std::map<int, Object *> m_objects;

tests/cannon.lua

@@ -34,3 +34,8 @@ function mousebutton_down_event(button)
         button1()
     end
 end
+
+--function update_overlay_event(width, height)
+--    local tw, th = ag.getTextSize("Hi there", 18)
+--    ag.drawText("Hi there", 1, 1, 1, 18, width - tw - 4, height - th - 4)
+--end