snake/game/MenuState.cxx

#include "MenuState.hxx"
#include "GameStateManager.hxx"
#include "../SDLRenderer.hxx"

void MenuState::update(GameStateManager& gsm, std::chrono::milliseconds delta_time)
{
  (void) delta_time;

  new_game_button_.set_on_click([&gsm] {
    gsm.replace_state(GameStates::Game);
  });

  quit_button_.set_on_click([&gsm] {
    while (gsm.current()!=nullptr) {
      gsm.pop_state();
    }
  });

  new_game_button_.update();
  quit_button_.update();

  auto const key_state = SDL_GetKeyboardState(nullptr);
  auto const escape_pressed = !!key_state[SDL_SCANCODE_ESCAPE];
  if (!escape_pressed && escape_pressed_) {
    gsm.pop_state();
  }
  escape_pressed_ = escape_pressed;
}

void MenuState::render(SDLRenderer& renderer)
{
  int screen_w, screen_h;
  SDL_GetRendererOutputSize(renderer, &screen_w, &screen_h);

  int const x = (screen_w-BUTTON_WIDTH)/2;
  int const y = (screen_h-(2*BUTTON_HEIGHT+20))/2;

  new_game_button_.move(x, y);
  quit_button_.move(x, y+BUTTON_HEIGHT+20);

  SDL_SetRenderDrawColor(renderer, 0, 0, 0, SDL_ALPHA_OPAQUE);
  SDL_RenderClear(renderer);

  new_game_button_.render(renderer);
  quit_button_.render(renderer);

  SDL_RenderPresent(renderer);
}