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FlappyWindow

Worked as Programmer
2025 August, 18 - 22
Language: c++

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I wanted to do something like this for a little while, I tried before in monogame but that didnt allow you to have multiple windows moving and running code at the same time. So I gave up after a while.

When we started working in C++ and SDL3 and I saw that you could easily make windows so I thought that maybe I could revive this idea. So I started experimenting by making the bird and spawning windows. When it worked I got exited and continued working. I added sprites, animated the bird, and scoring.

Something interesting that happend with the score text, When I wrote this line to change the window title:

SDL_SetWindowTitle(scoreWindow, "Score: " + score);

The text window took away letter by letter from the start and eventually started writing out error messages and other random things that it still removed letter by letter. What I think happend is that it set the text to the string I wrote but start at letter number score, eventually me and my classmates solved it by writing this instead:

SDL_SetWindowTitle(scoreWindow, std::format("Score: {}", score).c_str());

It formats the text and then converts the formatted string into characters since thats what the function needs.

Bird.cs

void Bird::Tick()
{
	switch (game->gameState)
	{
	case Game::GameState::Start:
		Start();
		break;
	case Game::GameState::Playing:
		Playing();
		break;
	case Game::GameState::Dead:
		Dead();
		break;
	}
}

void Bird::Start()
{
	position->y = 0;
	velocity = 0;
	const bool* keys = SDL_GetKeyboardState(NULL);
	SDL_PumpEvents();
	if (keys[SDL_SCANCODE_SPACE])
	{
		game->SetGameState(Game::GameState::Playing);
		std::cout << "Play" << '\n';
	}

	CoordinateConverter::SetWindowWorldPositionCentered(window, *(position));
}

void Bird::Playing()
{
	const bool* keys = SDL_GetKeyboardState(NULL);
	SDL_PumpEvents();
	velocity += gravity * game->fdata.deltaTime;
	if (keys[SDL_SCANCODE_SPACE] && !flapped) {
		if (velocity < 0)
		{
			velocity = flapPower;
		}
		else
		{
			velocity += flapPower * 0.75;
		}
		if (velocity > maxVelocity) { velocity = maxVelocity; }
		flapped = true;
	}
	if (!keys[SDL_SCANCODE_SPACE]) { flapped = false; }

	if (position->y > CoordinateConverter::worldHeight/2) //Ceiling handling
	{
 		velocity = 0;
		position->y = CoordinateConverter::worldHeight / 2;
	}
	else if (position->y < -CoordinateConverter::worldHeight / 2) //Floor handling
	{
		game->SetGameState(Game::GameState::Dead);
	}

	position->y += velocity * game->fdata.deltaTime;
	CoordinateConverter::SetWindowWorldPositionCentered(window, *(position));
}

void Bird::Dead()
{
	const bool* keys = SDL_GetKeyboardState(NULL);
	SDL_PumpEvents();
	if (keys[SDL_SCANCODE_SPACE])
	{
		game->SetGameState(Game::GameState::Start);
		std::cout << "Restart" << '\n';
	}
}

Bird::Bird(Game* game)
{
	this->game = game;
	window = SDL_CreateWindow("Bird", 100, 100, 0);
}

Screenshots