More abstraction for scripting languages

core/Input.cpp

@@ -20,29 +20,17 @@ void Input::Use(Window *window){
 }
 
 void Input::HandleKeys(Window *window, int keys, int code, int action, int mods) {
-#ifdef LUA_SCRIPTING
+  for (KeyHandler keyHandler : instance->keyHandlers) {
-  lua_State *L = (lua_State*) glfwGetWindowUserPointer(window);
+    keyHandler(window, keys, code, action, mods);
-  lua_getglobal(L, "onkey");
+  }
-  lua_pushinteger(L, keys);
-  lua_pushinteger(L, code);
-  lua_pushinteger(L, action);
-  lua_pushinteger(L, mods);
-  lua_call(L, 4, 0);
-#endif // LUA_SCRIPTING
 }
 
 void Input::HandleMousePosition(Window *window, double xpos, double ypos) {
   double relx = xpos - instance->lastx;
   double rely = ypos - instance->lasty;
-#ifdef LUA_SCRIPTING
+  for (MousePositionHandler mousePositionHandler : instance->mousePositionHandlers) {
-  lua_State *L = (lua_State*) glfwGetWindowUserPointer(window);
+    mousePositionHandler(window, xpos, ypos, relx, rely);
-  lua_getglobal(L, "onmousemotion");
+  }
-  lua_pushnumber(L, xpos);
-  lua_pushnumber(L, ypos);
-  lua_pushnumber(L, relx);
-  lua_pushnumber(L, rely);
-  lua_call(L, 4, 0);
-#endif // LUA_SCRIPTING
   instance->lastx = xpos;
   instance->lasty = ypos;
 }

core/Input.h

@@ -1,20 +1,21 @@
+#ifndef COUCH_H
+#define COUCH_H
 #include <GL/glew.h>
 #include <GLFW/glfw3.h>
 
-#ifdef LUA_SCRIPTING
+#include <vector>
-extern "C" {
-#include <lua.h>
-#include <lualib.h>
-#include <lauxlib.h>
-}
-#endif // LUA_SCRIPTING
 
 #include "types.h"
 
+typedef void (*KeyHandler)(Window *window, int key, int code, int action, int mods);
+typedef void (*MousePositionHandler)(Window *window, double xpos, double ypos, double xrel, double yrel);
+
 class Input {
 public:
   static Input *GetInstance();
   void Use(Window *window);
+  std::vector<KeyHandler> keyHandlers;
+  std::vector<MousePositionHandler> mousePositionHandlers;
 private:
   double lastx, lasty;
   Input();
@@ -22,3 +23,5 @@ private:
   static void HandleMousePosition(Window *window, double xpos, double ypos);
   static Input *instance;
 };
+
+#endif // COUCH_H

core/Lua.cpp

@@ -0,0 +1,90 @@
+#include "Lua.h"
+
+#ifdef LUA_SCRIPTING
+
+lua_State *Lua::L { luaL_newstate() };
+
+#endif // LUA_SCRIPTING
+
+void Lua::Initialize() {
+#ifdef LUA_SCRIPTING
+  language = this;
+  int err;
+  // Initialize Lua
+  luaopen_base(L);
+  luaopen_couch(L);
+  err = luaL_loadfile(L, "main.lua");
+  if (err == LUA_OK) {
+    err = lua_pcall(L, 0, 0, 0);
+    if (err != LUA_OK) {
+      Error();
+    }
+    lua_getglobal(L, "init");
+    err = lua_pcall(L, 0, 0, 0);
+    if (err != LUA_OK) {
+      Error();
+    }
+  } else if (err == LUA_ERRFILE) {
+    std::cerr << "Could not find main.lua." << std::endl;
+    exit(1);
+  } else {
+    // Syntax error
+    Error();
+  }
+
+  // Bind input functions
+  //glfwSetWindowUserPointer(window, (void*) L);
+  Input *input = Input::GetInstance();
+  input->keyHandlers.push_back(LuaKeyHandler);
+  input->mousePositionHandlers.push_back(LuaMousePositionHandler);
+#else // LUA_SCRIPTING
+  std::cerr << "Lua is selected as scripting language, but this binary was built without Lua support." << std::endl;
+  exit(1);
+#endif // LUA_SCRIPTING
+}
+
+void Lua::Update(double delta) {
+#ifdef LUA_SCRIPTING
+  lua_getglobal(L, "update");
+  lua_pushnumber(L, delta);
+  lua_call(L, 1, 0);
+#endif // LUA_SCRIPTING
+}
+
+void Lua::Close() {
+#ifdef LUA_SCRIPTING
+  lua_close(L);
+#endif // LUA_SCRIPTING
+}
+
+void Lua::Error() {
+#ifdef LUA_SCRIPTING
+  const char *error = lua_tolstring(L, -1, 0);
+  std::cerr << error << std::endl;
+#endif // LUA_SCRIPTING
+  exit(1);
+}
+
+void Lua::LuaKeyHandler(Window *window, int key, int code, int action, int mods) {
+#ifdef LUA_SCRIPTING
+  // lua_State *L = (lua_State*) glfwGetWindowUserPointer(window);
+  lua_getglobal(L, "onkey");
+  lua_pushinteger(L, key);
+  lua_pushinteger(L, code);
+  lua_pushinteger(L, action);
+  lua_pushinteger(L, mods);
+  lua_call(L, 4, 0);
+#endif // LUA_SCRIPTING
+}
+
+void Lua::LuaMousePositionHandler(Window *window, double xpos, double ypos, double relx, double rely) {
+#ifdef LUA_SCRIPTING
+  // lua_State *L = (lua_State*) glfwGetWindowUserPointer(window);
+  lua_getglobal(L, "onmousemotion");
+  lua_pushnumber(L, xpos);
+  lua_pushnumber(L, ypos);
+  lua_pushnumber(L, relx);
+  lua_pushnumber(L, rely);
+  lua_call(L, 4, 0);
+#endif // LUA_SCRIPTING
+}

core/Lua.h

@@ -0,0 +1,35 @@
+#ifndef LUA_H
+#define LUA_H
+
+#include <iostream>
+#include <stdlib.h>
+
+#include "Input.h"
+
+#ifdef LUA_SCRIPTING
+// Lua includes
+extern "C" {
+#include "lua.h"
+#include "lualib.h"
+#include "lauxlib.h"  
+}
+extern "C" int luaopen_couch(lua_State* L);
+#endif // LUA_SCRIPTING
+
+#include "ScriptingLanguage.h"
+
+class Lua : public ScriptingLanguage {
+public:
+  void Initialize();
+  void Update(double delta);
+  void Close();
+  void Error();
+private:
+#ifdef LUA_SCRIPTING
+  static lua_State *L;
+  static void LuaKeyHandler(Window *window, int key, int code, int action, int mods);
+  static void LuaMousePositionHandler(Window *window, double xpos, double ypos, double xrel, double yrel);
+#endif // LUA_SCRIPTING
+};
+
+#endif /* LUA_H */

core/ScriptingLanguage.cpp

@@ -0,0 +1,8 @@
+#include "ScriptingLanguage.h"
+
+ScriptingLanguage *ScriptingLanguage::language { nullptr };
+
+ScriptingLanguage *ScriptingLanguage::GetCurrentLanguage() {
+  return language;
+}
+

core/ScriptingLanguage.h

@@ -1,10 +1,15 @@
 #ifndef SCRIPTINGLANGUAGE_H
 #define SCRIPTINGLANGUAGE_H
 
-class ScriptingLangauge {
+class ScriptingLanguage {
-  void Initialize();
+public:
-  void Update();
+  virtual void Initialize() = 0;
-  void Close();
+  virtual void Update(double delta) = 0;
-}
+  virtual void Close() = 0;
+  virtual void Error() = 0;
+  static ScriptingLanguage *GetCurrentLanguage();
+protected:
+  static ScriptingLanguage *language;
+};
 
 #endif /* SCRIPTINGLANGUAGE_H */

core/couch.cpp

@@ -1,15 +1,6 @@
 // C++ includes
 #include <iostream>
 
-#ifdef LUA_SCRIPTING
-// Lua includes
-extern "C" {
-#include <lua.h>
-#include <lualib.h>
-#include <lauxlib.h>  
-}
-#endif // LUA_SCRIPTING
-
 // OpenGL Includes
 #include <GL/glew.h>
 #include <GLFW/glfw3.h>
@@ -22,6 +13,7 @@ extern "C" {
 #include "Camera.h"
 #include "Input.h"
 #include "Node.h"
+#include "Lua.h"
 
 Window *window;
 
@@ -30,12 +22,6 @@ const int height = 600;
 
 Node *root;
 
-#ifdef LUA_SCRIPTING
-
-extern "C" int luaopen_couch(lua_State* L);
-
-#endif // LUA_SCRIPTING
-
 void render(Node *curr, Shader shader, Matrix model) {
   if (curr->IsDrawable()) {
     if (curr->IsTransformable()) {
@@ -81,22 +67,6 @@ int main() {
 
   root = Node::GetRoot();
 
-#ifdef LUA_SCRIPTING
-  lua_State *L;
-  L = luaL_newstate();
-  luaopen_base(L);
-  luaopen_couch(L);
-  if (luaL_loadfile(L, "main.lua") == 0){
-    lua_call(L, 0, 0);
-    lua_getglobal(L, "init");
-    lua_call(L, 0, 0);
-  } else {
-    std::cerr << "Could not find main.lua" << std::endl;
-    return 1;
-  }
-  glfwSetWindowUserPointer(window, (void*) L);
-#endif // LUA_SCRIPTING
-
   Input *input = Input::GetInstance();
   input->Use(window);
 
@@ -108,6 +78,10 @@ int main() {
   Matrix projection = glm::perspective(glm::radians(45.0f), 800.0f/600.0f, 0.1f, 100.0f);
   shader.UpdateProjection(projection);
 
+  // TODO Allow multiple scripting languages
+  Lua *lua = new Lua();
+  lua->Initialize();
+
   double lastTime = glfwGetTime();
   double delta = 0.0;
 
@@ -115,6 +89,7 @@ int main() {
     glClearColor(0.5f, 0.5f, 0.5f, 1.0f);
     glClear(GL_COLOR_BUFFER_BIT);
 
+    lua->Update(delta);
 
     Matrix view(1.0f);
     Camera *camera = Camera::GetCurrentCamera();
@@ -124,16 +99,8 @@ int main() {
     view = glm::translate(view, -camera->transform.position);
     shader.UpdateView(view);
 
-
-#ifdef LUA_SCRIPTING
-    lua_getglobal(L, "update");
-    lua_pushnumber(L, delta);
-    lua_call(L, 1, 0);
-#endif // LUA_SCRIPTING
-
     // Render the scene tree
     render(root, shader, Matrix(1.0f));
-
     
     glfwSwapBuffers(window);
     glfwPollEvents();
@@ -143,12 +110,7 @@ int main() {
     lastTime = curTime;
   }
 
-#ifdef LUA_SCRIPTING
+  lua->Close();
-
-  lua_close(L);
-
-#endif // LUA_SCRIPTING
-  
   glfwDestroyWindow(window);
   glfwTerminate();
   return 0;

roadmap.md

@@ -27,3 +27,12 @@ I want to be able to build this for Windows
 - I have no clue what that entails
 - CMake?
 - How to run SWIG on windows?
+
+### Windows Compatible Postmortem
+Pretty brittle as a result of needing to download Windows binaries, but it works
+Eventually, we might need to include the source files as submodules, and build them all with CMake
+For now, what we've got is good
+
+### Better error messages
+Okay, now I want a message other than "main.lua not found!" if the lua file fucks up.
+Also, I want Lua errors to kill the program with an error message and a stack trace.