Initial commit

1 files changed, 137 insertions, 0 deletions

diff --git a/src/main.cpp b/src/main.cpp
new file mode 100644
index 0000000..9777a6f
--- /dev/null
+++ b/src/main.cpp
@@ -0,0 +1,137 @@
+#include <SDL2/SDL.h>
+#include <iostream>
+#include "lua/lua.hpp"
+
+#define WIDTH 1280
+#define HEIGHT 720
+#define KEYSYM event.key.keysym.sym
+
+SDL_Rect rect = {WIDTH/2, HEIGHT/2, 50, 50};
+
+constexpr char* LUA_FILE = R"(
+movementSpeed = 3;
+
+function Setup()
+end
+
+function Update()
+    if keys[getKeycodeByName("RIGHT")] or keys[getKeycodeByName("D")] then
+        movePlayer(movementSpeed, 0)
+    end
+    if keys[getKeycodeByName("LEFT")] or keys[getKeycodeByName("A")] then
+        movePlayer(movementSpeed * -1, 0)
+    end
+    if keys[getKeycodeByName("DOWN")] or keys[getKeycodeByName("S")] then
+        movePlayer(0, movementSpeed)
+    end
+    if keys[getKeycodeByName("UP")] or keys[getKeycodeByName("W")] then
+        movePlayer(0, movementSpeed * -1)
+    end
+end
+)";
+
+int l_move_rect(lua_State* L) {
+    int dx = luaL_checkinteger(L, 1);
+    int dy = luaL_checkinteger(L, 2);
+    rect.x += dx;
+    rect.y += dy;
+    return 0;
+}
+
+int l_keycode_from_string(lua_State* L) {
+    const char* keystr = luaL_checkstring(L, 1);
+    
+    int scancode = -2;
+    
+    if (strcmp(keystr, "RIGHT") == 0) scancode = SDL_SCANCODE_RIGHT;
+    else if (strcmp(keystr, "LEFT") == 0) scancode = SDL_SCANCODE_LEFT;
+    else if (strcmp(keystr, "UP") == 0) scancode = SDL_SCANCODE_UP;
+    else if (strcmp(keystr, "DOWN") == 0) scancode = SDL_SCANCODE_DOWN;
+    else if (strcmp(keystr, "D") == 0) scancode = SDL_SCANCODE_D;
+    else if (strcmp(keystr, "A") == 0) scancode = SDL_SCANCODE_A;
+    else if (strcmp(keystr, "S") == 0) scancode = SDL_SCANCODE_S;
+    else if (strcmp(keystr, "W") == 0) scancode = SDL_SCANCODE_W;
+    
+    scancode += 1;
+
+    lua_pushinteger(L, scancode);
+    return 1;
+}
+
+void push_keys_to_lua(lua_State* L, bool keys[SDL_NUM_SCANCODES]) {
+    lua_newtable(L);  // create a new table on the stack
+    
+    for (int i = 0; i < SDL_NUM_SCANCODES; i++) {
+        lua_pushinteger(L, i + 1);
+        lua_pushboolean(L, keys[i]);
+        lua_settable(L, -3);
+    }
+}
+
+void call_lua_function(lua_State* L, const char* func_name) {
+    lua_getglobal(L, func_name);
+    if (lua_isfunction(L, -1)) {
+        if (lua_pcall(L, 0, 0, 0) != LUA_OK) {
+            std::cerr << "Lua Error in " << func_name << ": " << lua_tostring(L, -1) << std::endl;
+            lua_pop(L, 1);
+        }
+    } else {
+        lua_pop(L, 1);
+    }
+}
+
+
+int main() {
+    lua_State* L = luaL_newstate();
+    luaL_openlibs(L);
+    lua_register(L, "movePlayer", l_move_rect);
+    lua_register(L, "getKeycodeByName", l_keycode_from_string);
+    luaL_dostring(L, LUA_FILE);
+
+    SDL_Window* window = nullptr;
+    SDL_Renderer* renderer = nullptr;
+    SDL_Event event;
+
+    bool keys[SDL_NUM_SCANCODES] = {false};
+    bool running = true;
+
+    push_keys_to_lua(L, keys);
+    lua_setglobal(L, "keys");
+
+    SDL_Init(SDL_INIT_EVERYTHING);
+    SDL_CreateWindowAndRenderer(WIDTH, HEIGHT, 0, &window, &renderer);
+
+    call_lua_function(L, "Setup");
+
+    while (running) {
+        while (SDL_PollEvent(&event)) {
+            if (event.type == SDL_QUIT) {
+                running = false;
+            }
+
+            if (event.type == SDL_KEYDOWN) {
+                keys[event.key.keysym.scancode] = true;
+            }
+            if (event.type == SDL_KEYUP) {
+                keys[event.key.keysym.scancode] = false;
+            }
+        }
+
+        push_keys_to_lua(L, keys);
+        lua_setglobal(L, "keys");
+
+        call_lua_function(L, "Update");
+
+        SDL_SetRenderDrawColor(renderer, 0, 0, 0, 255);
+        SDL_RenderClear(renderer);
+
+        SDL_SetRenderDrawColor(renderer, 255, 0, 0, 255);
+        SDL_RenderFillRect(renderer, &rect);
+
+        SDL_RenderPresent(renderer);
+        SDL_Delay(10);
+    }
+
+    lua_close(L);
+    return 0;
+}