Fix main loop, add example and cleanup

include/app/app.h

@@ -1,3 +1,6 @@
+#ifndef APP_H
+#define APP_H
+
 #include "binding/ruby.h"
 #include "localization/localization.h"
 #include "utils.h"
@@ -25,11 +28,10 @@ struct Element {
   }
 };
 
-struct Image : Element {
+struct EImage : Element {
   Animation animation;
-  float alpha = 1.0f;
 
-  Image(Animation animation) : animation(std::move(animation)) {}
+  EImage(Animation animation) : animation(std::move(animation)) {}
 
   Vec2<float> size(Window *window) override {
     if (animation.frames.empty())
@@ -42,24 +44,24 @@ struct Image : Element {
       return;
 
     int frame_index = (int)((abs_time * animation.frame_rate) / 1000) % animation.frames.size();
-    window.draw(animation.frames[frame_index], position, z, rotation, scale, alpha);
+    window.draw(animation.frames[frame_index], position, z, rotation, scale);
   }
 };
 
-struct Text : Element {
+struct EText : Element {
   Localization::Key key;
   int font_id;
   int font_size = 16;
   Color color = {255, 255, 255, 255};
 
-  Text(Localization::Key key, int font_id, int font_size, Color color)
+  EText(Localization::Key key, int font_id, int font_size, Color color)
       : key(key), font_id(font_id), font_size(font_size), color(color) {}
 
   Vec2<float> size(Window *window) override {
     return window->get_text_size(text_id);
   };
 
-  void render(Window &window, uint64_t abs_time) override {
+  void render(Window &window, uint64_t) override {
     if (last_language != Localization::current_language || last_key != key || text_id == -1) {
       std::string localized_str = Localization::get(key);
       if (text_id != -1)
@@ -86,12 +88,12 @@ struct ERect : Element {
 
   ERect(Vec2<float> shape, Color color) : shape(shape), color(color) {}
 
-  void render(Window &window, uint64_t abs_time) override {
+  void render(Window &window, uint64_t) override {
     window.draw_rect(Rect::from_size(position, shape), color, z, rotation);
   }
 };
 
-extern Pool<std::unique_ptr<Element>> element_pool;
+inline Pool<Element *> element_pool;
 
 struct Scene {
   std::vector<int> element_ids;
@@ -120,7 +122,7 @@ struct Scene {
 
   void click(Window *window, Vec2<float> position) {
     for (auto it = element_ids.rbegin(); it != element_ids.rend(); ++it) {
-      Element *e = element_pool[*it].get();
+      Element *e = element_pool[*it];
       Vec2<float> size = e->size(window);
       Rect rect = Rect::from_size(e->position, size * e->scale);
       if (rect.contains(position)) {
@@ -139,31 +141,39 @@ struct Scene {
   }
 };
 
-extern Pool<std::unique_ptr<Scene>> scene_pool;
+inline Pool<Scene *> scene_pool;
 
 struct App {
-  Window window;
   int current_scene_id = 0;
   bool running = true;
 
-  App(Vec2<float> size, const char *title, Animation loading_animation)
+  App(Vec2<float> size, const char *title, Animation loading_animation) {
-      : window(size, title) {
+    window.update(size, title);
-    std::unique_ptr<Scene> loading_scene = std::make_unique<Scene>();
 #warning "Should try to center the loading image or scale it to fit the screen"
-    std::unique_ptr<Image> image = std::make_unique<Image>(loading_animation);
+    Scene *loading_scene = new Scene{};
-    int image_id = element_pool.acquire(std::move(image));
+    EImage *image = new EImage(loading_animation);
+    int image_id = element_pool.acquire(image);
     loading_scene->add_element(image_id);
-    scene_pool.acquire(std::move(loading_scene));
+    scene_pool.acquire(loading_scene);
   }
 
   void loop() {
+    const uint64_t target_ms = 1000 / 60;
+
+    uint64_t time_a = window.get_time();
+    uint64_t time_b = window.get_time();
+
     while (running) {
+      time_a = window.get_time();
+      uint64_t frame_time = time_a - time_b;
+      if (frame_time <= target_ms)
+        usleep((target_ms - frame_time) * 1000);
+
+      time_b = window.get_time();
+
       uint64_t dt = window.delta_time();
-      uint64_t abs_time = window.get_time();
 
-      Scene *scene = scene_pool[current_scene_id].get();
+      Scene *scene = scene_pool[current_scene_id];
-
-      scene->update_scene(dt);
 
       Event e;
       while (window.poll(e)) {
@@ -173,6 +183,7 @@ struct App {
           break;
         case Event::MOUSE_BUTTON_DOWN:
           scene->click(&window, e.mouse_button.position);
+          printf("DT: %lu ms\n", dt);
           break;
         default:
           break;
@@ -180,10 +191,15 @@ struct App {
         window.consume(e);
       }
 
-      scene->render(window, abs_time);
+      scene->update_scene(dt);
+      scene->render(window, window.get_time());
 
       window.render();
+
+      window.clear();
     }
   }
 };
 } // namespace app
+
+#endif

include/binding/ruby.h

@@ -2,7 +2,7 @@
 #include "utils.h"
 
 namespace Ruby {
-extern mrb_state *mrb;
+inline mrb_state *mrb = mrb_open();
 struct Block {
   mrb_value proc;
 

include/utils.h

@@ -158,11 +158,6 @@ struct Rect {
 
 template <typename T>
 struct Pool {
-  Pool() {
-    items.reserve(20);
-    free_indices.reserve(20);
-  }
-
   T &operator[](int index) {
     return items[index];
   }
@@ -175,10 +170,10 @@ struct Pool {
     if (!free_indices.empty()) {
       int index = free_indices.back();
       free_indices.pop_back();
-      items[index] = item;
+      items[index] = std::move(item);
       return index;
     } else {
-      items.push_back(item);
+      items.push_back(std::move(item));
       return items.size() - 1;
     }
   }

include/window/window.h

@@ -4,6 +4,11 @@
 #include "pch.h"
 #include "utils.h"
 
+struct Image {
+  SDL_Texture *texture;
+  Vec2<float> size;
+};
+
 struct Font {
   TTF_Font *font;
   bool pixel_art;
@@ -59,11 +64,12 @@ public:
   // title can be free'd by the caller after the window is created, as it's copied internally.
   Window(Vec2<float> size, const char *title);
 
+  void update(Vec2<float> new_size, const char *new_title);
+
   ~Window();
 
   // Rendering functions
-
+  int load_image(const char *path, float alpha = 1.0f, bool pixel_art = false);
-  int load_image(const char *path, bool pixel_art = false);
   void unload_image(int image_id);
   Vec2<float> get_image_size(int image_id);
 
@@ -77,7 +83,7 @@ public:
 
   bool write(int text_id, Vec2<float> position, float z, float angle = 0.0f, Vec2<float> scale = {1.0f, 1.0f});
 
-  bool draw(int image_id, Vec2<float> position, float z, float angle = 0.0f, Vec2<float> scale = {1.0f, 1.0f}, float alpha = 1.0f);
+  bool draw(int image_id, Vec2<float> position, float z, float angle = 0.0f, Vec2<float> scale = {1.0f, 1.0f});
 
   bool draw_rect(Rect rect, Color color, float z, float angle = 0.0f);
 
@@ -123,10 +129,10 @@ private:
   SDL_Texture *white_tex;
 
   // Image pool
-  Pool<SDL_Texture *> image_pool;
+  Pool<Image> image_pool;
 
   // Font pool
-  Pool<struct Font> font_pool;
+  Pool<Font> font_pool;
 
   // Text pool
   Pool<SDL_Texture *> text_pool;
@@ -146,7 +152,6 @@ private:
       struct {
         int image_id;
         Vec2<float> position;
-        float alpha;
       } draw_image;
 
       struct {
@@ -172,4 +177,6 @@ private:
   void draw_letterbox();
 };
 
+inline Window window({720, 480}, "Mysth Engine");
+
 #endif

samples/button.rb

@@ -1,4 +1,4 @@
-app = App.new 400, 400, title: "Button Test"
+App.run 400, 400, title: "Button Test"
 
 main_scene = Scene.new
 
@@ -15,7 +15,11 @@ rect.on_click do
     0xFF0000
 end
 
+main_scene.update do |dt|
+  puts "Delta time: #{dt}ms"
+end
+
 main_scene << text
 main_scene << rect
 
-app.start main_scene
+App.start main_scene

samples/main.rb

@@ -5,15 +5,15 @@ width, height = 720, 480
 
 image = Tiles.from("assets/loading.png").first
 
-app = App.new width, height, title: "My Game", loading_bg: image # can be image or animation
+App.run width, height, title: "My Game", loading_bg: image # can be image or animation
 
-app.map_key ?w, :forward
+App.map_key ?w, :forward
-app.map_key ?s, :backward
+App.map_key ?s, :backward
-app.map_key ?a, :left
+App.map_key ?a, :left
-app.map_key ?d, :right
+App.map_key ?d, :right
 
-app.map_key ?h, :heal
+App.map_key ?h, :heal
-app.map_key ?t, :place
+App.map_key ?t, :place
 
 menu_scene = Scene.new
 
@@ -24,7 +24,7 @@ start_button = ElementText.new "Start Game", font: default_font, position: {x: 1
 game_scene = Scene.new
 
 start_button.on_click do
-  app.start game_scene
+  App.start game_scene
 end
 
 menu_scene << start_button
@@ -184,4 +184,4 @@ world.shader :fog do |shader|
   z = 100 # shaders always appear above normal sprites but z is used to sort them relative to each other, so a shader with z 100 will appear above a shader with z 50, but both will appear above normal sprites
 end
 
-app.start menu_scene # first scene to show when the game starts, stops the loading bg
+App.start menu_scene # first scene to show when the game starts, stops the loading bg

src/main.cc

@@ -1,67 +1,19 @@
-#include "window/window.h"
+#include "app/app.h"
+
+using namespace app;
 
 int main() {
-  printf("Starting engine...\n");
+  int loading_image = window.load_image("assets/images/menu_bg.png", 1.0f, true);
 
-  Window w({800, 600}, "Render Test");
+  Animation loading_animation = {
+    .frames = {loading_image},
+    .frame_rate = 1.0f, // Not animated, so frame rate doesn't matter
+    .loop = false
+  };
 
-  int img = w.load_image("./assets/images/arrow.png", true);
+  App app({720, 480}, "Mysth Engine", loading_animation);
-  int font = w.load_font(
-    "./assets/fonts/charybdis.ttf",
-    24,
-    false,
-    false,
-    false,
-    true
-  );
 
-  int text = w.create_text(font, "Hello Engine", 12, {255, 255, 255, 255});
+  app.loop();
-
-  float t = 0.0f;
-
-  bool running = true;
-
-  printf("Entering main loop...\n");
-
-  while (running) {
-    Event e;
-    while (w.poll(e)) {
-      switch (e.type) {
-      case Event::QUIT:
-        printf("Exiting\n");
-        running = false;
-        break;
-      case Event::KEY_DOWN:
-        printf("Key down: %d\n", e.key.key);
-        if (e.key.key == 41) {
-          printf("Exiting\n");
-          running = false;
-        }
-        break;
-      default:
-        break;
-      }
-      w.consume(e);
-    }
-
-    w.clear();
-
-    // animated position
-    t += 0.016f;
-    float x = 200 + std::sin(t) * 100;
-    float y = 150 + std::cos(t) * 100;
-
-    // background rect (low z)
-    w.draw_rect({{0, 0}, {800, 600}}, {20, 20, 30, 255}, 0, 20.0f);
-
-    // image (mid z)
-    w.draw(img, {x, y}, 1.0f, t * 50.0f, {2.0f, 2.0f}, 1.0f);
-
-    // text (top z)
-    w.write(text, {0, 0}, 2.0f, 0.0f, {1.0f, 1.0f});
-
-    w.render();
-  }
 
   return 0;
 }

src/window/window.cc

@@ -29,10 +29,20 @@ Window::Window(Vec2<float> size, const char *title) {
   SDL_UpdateTexture(white_tex, nullptr, &pixel, sizeof(pixel));
 };
 
+void Window::update(Vec2<float> new_size, const char *new_title) {
+  if (new_size.x > 0 && new_size.y > 0) {
+    virtual_size = new_size;
+    compute_transform();
+  }
+
+  if (new_title)
+    SDL_SetWindowTitle(window, new_title);
+}
+
 Window::~Window() {
-  for (auto tex : image_pool.all())
+  for (auto &tex : image_pool.all())
-    if (tex)
+    if (tex.texture)
-      SDL_DestroyTexture(tex);
+      SDL_DestroyTexture(tex.texture);
 
   for (auto tex : text_pool.all())
     if (tex)
@@ -48,7 +58,7 @@ Window::~Window() {
   SDL_Quit();
 }
 
-int Window::load_image(const char *path, bool pixel_art) {
+int Window::load_image(const char *path, float alpha, bool pixel_art) {
   SDL_Texture *texture = IMG_LoadTexture(renderer, path);
 
   if (pixel_art) {
@@ -60,7 +70,20 @@ int Window::load_image(const char *path, bool pixel_art) {
     return UINT32_MAX;
   }
 
-  return image_pool.acquire(texture);
+  SDL_SetTextureAlphaMod(texture, (uint8_t)(alpha * 255));
+
+  float w, h;
+  SDL_GetTextureSize(texture, &w, &h);
+
+  return image_pool.acquire({texture, {w, h}});
+}
+
+Vec2<float> Window::get_image_size(int image_id) {
+  if (!image_pool.is_valid(image_id)) {
+    fprintf(stderr, "Invalid image ID: %d\n", image_id);
+    return {0, 0};
+  }
+  return {image_pool[image_id].size.x, image_pool[image_id].size.y};
 }
 
 void Window::unload_image(int image_id) {
@@ -69,7 +92,7 @@ void Window::unload_image(int image_id) {
     return;
   }
 
-  SDL_DestroyTexture(image_pool[image_id]);
+  SDL_DestroyTexture(image_pool[image_id].texture);
   image_pool.release(image_id);
 }
 
@@ -132,6 +155,16 @@ int Window::create_text(int font_id, const char *text, uint32_t length, Color co
   return text_pool.acquire(texture);
 }
 
+Vec2<float> Window::get_text_size(int text_id) {
+  if (!text_pool.is_valid(text_id)) {
+    fprintf(stderr, "Invalid text ID: %d\n", text_id);
+    return {0, 0};
+  }
+  float w, h;
+  SDL_GetTextureSize(text_pool[text_id], &w, &h);
+  return {w, h};
+}
+
 void Window::unload_text(int text_id) {
   if (!text_pool.is_valid(text_id)) {
     fprintf(stderr, "Invalid text ID: %d\n", text_id);
@@ -162,7 +195,7 @@ bool Window::write(int text_id, Vec2<float> position, float z, float angle, Vec2
   return true;
 };
 
-bool Window::draw(int image_id, Vec2<float> position, float z, float angle, Vec2<float> scale, float alpha) {
+bool Window::draw(int image_id, Vec2<float> position, float z, float angle, Vec2<float> scale) {
   if (!image_pool.is_valid(image_id)) {
     fprintf(stderr, "Invalid image ID: %d\n", image_id);
     return false;
@@ -176,7 +209,6 @@ bool Window::draw(int image_id, Vec2<float> position, float z, float angle, Vec2
      .draw_image = {
        .image_id = image_id,
        .position = position,
-       .alpha = alpha,
      }}
   );
 
@@ -236,9 +268,7 @@ void Window::render() {
   std::stable_sort(
     render_instructions.begin(),
     render_instructions.end(),
-    [](const RenderInstruction &a, const RenderInstruction &b) {
+    [](const RenderInstruction &a, const RenderInstruction &b) { return a.z < b.z; }
-      return a.z < b.z;
-    }
   );
 
   for (const RenderInstruction &instruction : render_instructions) {
@@ -277,10 +307,7 @@ void Window::render() {
     } break;
 
     case RenderInstruction::DRAW_IMAGE: {
-      SDL_Texture *texture = image_pool[instruction.draw_image.image_id];
+      Image image = image_pool[instruction.draw_image.image_id];
-
-      float w, h;
-      SDL_GetTextureSize(texture, &w, &h);
 
       SDL_FlipMode flip = SDL_FLIP_NONE;
 
@@ -295,14 +322,12 @@ void Window::render() {
       SDL_FRect dst_rect;
       dst_rect.x = instruction.draw_image.position.x * scale + offset.x;
       dst_rect.y = instruction.draw_image.position.y * scale + offset.y;
-      dst_rect.w = scale_x * w;
+      dst_rect.w = scale_x * image.size.x;
-      dst_rect.h = scale_y * h;
+      dst_rect.h = scale_y * image.size.y;
-
-      SDL_SetTextureAlphaMod(texture, static_cast<Uint8>(instruction.draw_image.alpha * 255));
 
       SDL_RenderTextureRotated(
         renderer,
-        texture,
+        image.texture,
         nullptr,
         &dst_rect,
         instruction.angle,