Messages

76

General discussions / Re: 50% Discount on SFML e-books!

« on: May 07, 2015, 11:09:43 am »

All the SFML Books are on sale at the moment at packtpub, so the promo code does not give any further discount. Normal Price for SFML Game Development is something round 30€, SFML Essentials is at ~18€, and the preorder for SFML Blueprints was something round 38€ yesterday.

77

General discussions / Re: 50% Discount on SFML e-books!

« on: May 06, 2015, 12:51:32 pm »

O damn, I just ordered SFML Essentials last week, to bad 

78

General discussions / Re: What strategies/learning techniques helped you in learning game development

« on: April 22, 2015, 03:09:04 pm »

Reading this reminds me off myself 3 years ago, so I think I can give some advice back for what I learned and how I did it the last 3 years

After I knew I want to use C++ and SFML (tackled SDL a bit also) I looked for articles on how "to start learning" game development. I found this article on how to start. It clearly tells you, you start by just doing it, with easy starting projects and advance from there.

So I started learning some SFML via the examples provided by SFML itself. After that I started Pong as my first project. I got it working after 20 to 25 hours of coding I think. No menus, no sound, no music, just the pure game. From there I wanted to fine tune the game, add menus, sounds and so on. I found this tutorial which explains how to build Pong with SFML and all these cool features. Careful, no C++11 used, the code quality can be updated to be a lot better, but it gives you an idea on how and why to do things.
From there on I rewrote my first Pong version six times now, and I'm still not completely satisfied with the result Which leads to the second learning aspect: After you finish something, revisite the code and refactor it, get rid off owning raw pointers, decouple the game objects and so on...

Early 2014 I bought the book SFML Game Development and started working on it. The concepts in there proved very valuable to me, especially the state stack and the context patterns used. From there I read the already mentioned online book Game Programming Patterns which is an awesome read, after you grasped the code of SFML Game Development. After that I bought a (german only) book dedicated on learning C++11 to get all those new cool C++ features which were tackled in the SFML Book.

After that everything in the code base made so much more sense to me and with having the proper knowledge and tools on how to program, I started making a Breakout clone. Not finished yet but hopefully in a few weeks. Which leads me to my last point: finish what you started. Take a small scope project and finish it, make it work. This gives you the satisfaction that you achieved it, which in turn motivates you to go on with the next project, which should add some new feature you never programmed before.

So short answer: Take it easy, start small, advance in little steps. Revisite what you did and make it better. Strife to be a better programmer.

Hope that helps you, as it helped me a lot.
Cheers and all success!

Edit: Oh and I completely forgot one of the most important things, something I had to learn the hard way: Get your math right. 2D vector math is your bread and butter, even for such a "simple" game like Pong. Some focus points: unit vector, length of a vector, carthesian and polar coordinates, radians and degrees

79

SFML projects / Re: Rage - a "modern" rogue-like

« on: April 07, 2015, 04:05:35 pm »

Also I plan to write more about e.g. my entity-component system or other parts (pathfinding, dungeon generator etc.).

So if someone is curious about some implementation details, just ask!

Well yeah, ECS is something I'm looking into right now, I nailed the theory down, but I cannot come up with a good implementation in C++. If you could show the basic concepts (Is there an entity class, or is there only an unique ID somewhere for example) and some headers, this would be awesome, cause I couldn't find such information on the net yet.

Thanks and keep up the good work

80

General discussions / Re: SFML Game Development -- A book on SFML

« on: April 07, 2015, 10:53:14 am »

One question to your approach of a "debug state": How can you calculate the correct fps when it is done via a state in the state stack? The state stack is updated with a fixed time step and therefore you cannot count the number of rendered frames? I wonder how the Application::updateStatistics - Member could be refactored into a member function of a debug state for that purpose?

81

General / Re: Repeating a texture when using a tileset

« on: March 04, 2015, 11:15:30 am »

When using a sprite atlas as shown, do yourself a favor and look at sf::VertexArray. It's just the best solution to your problem and scales in the long run performance-wise.
I know that for sure, as I just conquered the same "problem"

82

General / Re: Usage of GetLocalBounds()

« on: March 03, 2015, 11:48:22 am »

Typical use case for this is to set the origin of the sprite to its center point.
Something like this:

auto bounds = mySprite.getLocalBounds();
mySprite.setOrigin( bounds.width / 2.f, bounds.heigth / 2.f );
 

Other use cases is for collision detection between sprites, you need to know about the geometry of the sprite, and therefor can use getLocalBounds().

83

SFML website / Re: Precompiled binaries Linux 64bit problem

« on: March 03, 2015, 11:42:17 am »

Same for Ubuntu x64: /usr/local/lib for 64Bit and /usr/local/lib32 for 32Bit obviously.

84

SFML projects / Re: PIONEERS

« on: February 24, 2015, 02:15:50 pm »

Just wanted to hop in and say that the graphics style of this game is super awesome. And I mean super awesome! Will download and try it out!

85

Feature requests / Re: new sf::Sprite Method "void centerOrigin()"

« on: February 12, 2015, 09:44:14 am »

Hmm, ok if such a function could not be generalized, then I think it won't be a valuable addition versus user defined functions.
I'm  tottaly ok with that, this clears this question up for me.
Thanks.

86

Feature requests / Re: new sf::Sprite Method "void centerOrigin()"

« on: February 11, 2015, 03:14:56 pm »

As I already stated in my previous request, setting specific relative origins (top-left, top-center, top-right etc.) would come in handy, not only centering the origin. Implementing offsets for the relative alignment would also be a nice addition. For me the rasterization "issue" with uneven sprites is not present, I have never worked with uneven sprites, I always work with sprite sizes in powers of 2 cause it makes life easier. But this "problem" could easily be adressed by such a function.

I still fully support this feature request. (And this time a response would be nice ;-) )

87

General / Re: Game resolution dilemma

« on: January 30, 2015, 02:56:16 pm »

As I am at the moment also working with views, this is a good resource to conquer the "resolution problem".
Thanks guys for all the input, greatly appreciated!

88

System / Re: Contruction sf::Vector2f from sf::FloatRect - Wrong values

« on: January 30, 2015, 08:21:09 am »

Doh, going over the code hundreds of times and I didn't notice the wrong order in the class declaration. Just one of those days I guess. Thanks, it works now! 

89

System / [Solved] Contruction sf::Vector2f from sf::FloatRect - Wrong values

« on: January 29, 2015, 04:13:57 pm »

Hi Folks,

I have a pretty weird problem with contructing a sf::Vector2f from a sf::FloatRect, the x and y values of the vector are wrong. I create a sf::FloatRect for my game world, and want to create a sf::Vector2f for the spawn point of my character, which should spawn in the middle of the game world. I calculate the spawn position like this:

GameWorld::GameWorld( sf::RenderWindow& window)
  : _window( window )
[ ... ]
  , _worldBounds( 0.f, 0.f, 1600.f, 1200.f )
  //, _spawnPosition( 800.f, 600.f )
  , _spawnPosition( _worldBounds.width / 2.f, _worldBounds.height / 2.f )
 

The result should be 800, 600, but in reality is
_spawnPosition.x = -53687088.000000
_spawnPosition.y = -53687088.000000

Code architecture is based on the SFML Book code base.
Code Example

(click to show/hide)

GameWorld.hpp

#pragma once
#include <SFML/Graphics/RenderWindow.hpp>
#include <SFML/Graphics/Sprite.hpp>
#include <SFML/Graphics/Texture.hpp>
#include <SFML/System/Time.hpp>

class GameWorld
{
public:
  explicit GameWorld( sf::RenderWindow& window );
  void update( sf::Time dt );
  void draw();

private:
  void loadTextures();
  void buildScene();

  sf::Sprite _playerSprite;
  sf::Sprite _floorSprite;
  sf::Texture _playerTexture;
  sf::Texture _floorTexture;
  sf::RenderWindow& _window;
  sf::Vector2f _spawnPosition;
  sf::FloatRect _worldBounds;
  sf::View _worldView;
};
 

GameWorld.cpp

#include <app/GameWorld.hpp>
#include <iostream>

GameWorld::GameWorld( sf::RenderWindow& window)
  : _window( window )
  , _playerSprite()
  , _playerTexture()
  , _floorSprite()
  , _floorTexture()
  , _worldView( window.getDefaultView() )
  , _worldBounds( 0.f, 0.f, 1600.f, 1200.f )
  //, _spawnPosition( 800.f, 600.f )
  , _spawnPosition( _worldBounds.width / 2.f, _worldBounds.height / 2.f )
{
  loadTextures();
  buildScene();

  std::cout << "_worldView.x = " << std::to_string( _worldView.getSize().x ) << std::endl;
  std::cout << "_worldView.y = " << std::to_string( _worldView.getSize().y ) << std::endl;

  std::cout << "_worldView.center.x = " << std::to_string( _worldView.getCenter().x ) << std::endl;
  std::cout << "_worldView.center.y = " << std::to_string( _worldView.getCenter().y ) << std::endl;

  std::cout << "_playerSprite.x = " << std::to_string( _playerSprite.getPosition().x ) << std::endl;
  std::cout << "_playerSprite.y = " << std::to_string( _playerSprite.getPosition().y ) << std::endl;

  std::cout << "_spawnPosition.x = " << std::to_string( _spawnPosition.x ) << std::endl;
  std::cout << "_spawnPosition.y = " << std::to_string( _spawnPosition.y ) << std::endl;

  std::cout << "_worldBounds.x = " << std::to_string( _worldBounds.width ) << std::endl;
  std::cout << "_worldBounds.y = " << std::to_string( _worldBounds.height ) << std::endl;
}

void GameWorld::update( const sf::Time dt )
{
  _worldView.move( 25.f * dt.asSeconds(), 25.f * dt.asSeconds() );
}

void GameWorld::draw()
{
  _window.setView( _worldView );
  _window.draw( _floorSprite );
  _window.draw( _playerSprite );
}

void GameWorld::loadTextures()
{
  if( !_playerTexture.loadFromFile( "../media/male.png" ) ) {
    throw std::runtime_error( "Could not load image file 'male.png'" );
  }

  if( !_floorTexture.loadFromFile( "../media/grass.png" ) ) {
    throw std::runtime_error( "Could not load image file 'grass.png'" );
  }
}

void GameWorld::buildScene()
{
  _playerSprite.setTexture( _playerTexture );
  auto bounds = _playerSprite.getLocalBounds();
  _playerSprite.setOrigin( bounds.width / 2.f, bounds.height / 2.f );
  _playerSprite.setPosition( _spawnPosition );

  _floorTexture.setRepeated( true );
  _floorSprite.setTexture( _floorTexture );
  _floorSprite.setTextureRect( sf::IntRect( _worldBounds ) );
  _floorSprite.setPosition( _worldBounds.left, _worldBounds.top );

  _worldView.setCenter( _spawnPosition );
}

 

Application.cpp

#include <app/Application.hpp>
#include <SFML/Window/Event.hpp>

Application::Application()
  : _window( { 800, 600 }, "Game Demo", sf::Style::Close )
  , _timeStep( sf::seconds( 1.f / 60.f ) )
  , _gameWorld( _window )
{
}

void Application::run()
{
  sf::Clock appClock;
  sf::Time timeSinceLastFrame{ sf::Time::Zero };

  while( _window.isOpen() ) {
    sf::Time dt = appClock.restart();
    timeSinceLastFrame += dt;

    while( timeSinceLastFrame > _timeStep ) {
      timeSinceLastFrame -= _timeStep;

      handleEvents();
      update( _timeStep );      
    }

    render();
  }
}

void Application::handleEvents()
{
  sf::Event evt;

  while( _window.pollEvent( evt ) ) {
    if( evt.type == sf::Event::Closed ) {
      _window.close();
    }
  }
}

void Application::update( const sf::Time dt)
{
  _gameWorld.update( dt );
}

void Application::render()
{
  _window.clear();

  _gameWorld.draw();

  _window.display();
}
 

Visual Studio 2013.4 with SFML 2.2 stable

I can't track down the source of the problem. Any thoughts?
Every suggestion welcome, I go crazy about this.

Cheers!

90

General discussions / Re: SFML 2.2 Released!

« on: December 17, 2014, 09:35:42 am »

Congratulations for finishing SFML 2.2. beforce christmas. Makes you sleep a bit better the next days I think
Will start working with it over the holidays. Thanks Guys.