So I'm new to c++ and SMFL. I'm trying to set a background image and have it fill the window as much as possible to, filling either top to bottom or left to right depending on the image and window dimensions. I have tried that letter boxing wiki that shows up in all the searches, and serval other things.
With the View/letter boxing the image centers but doesn't scale. with my attempts I can get it to fill the width but won't maintain aspect ratio. Here are to two codes I've tried:
//Letterbox code always referred to on these forms
sf::View getLetterboxView(sf::View view, sf::Vector2u windowSize) {
// Compares the aspect ratio of the window to the aspect ratio of the view,
// and sets the view's viewport accordingly in order to archieve a letterbox effect.
// A new view (with a new viewport set) is returned.
float windowRatio = (float)windowSize.x / windowSize.y;
float viewRatio = (float)view.getSize().x / view.getSize().y;
float sizeX = 1;
float sizeY = 1;
float posX = 0;
float posY = 0;
bool horizontalSpacing = true;
if (windowRatio < viewRatio) horizontalSpacing = false;
// If horizontalSpacing is true, the black bars will appear on the left and right side.
// Otherwise, the black bars will appear on the top and bottom.
if (horizontalSpacing) {
sizeX = viewRatio / windowRatio;
posX = (1 - sizeX) / 2.f;
}
else {
sizeY = windowRatio / viewRatio;
posY = (1 - sizeY) / 2.f;
}
view.setViewport(sf::FloatRect(posX, posY, sizeX, sizeY));
return view;
}
//My own attempts
sf::Sprite setBackground(sf::Vector2u windowSize, sf::Texture& background) //preps image background
{
sf::Sprite backgroundSprite;
backgroundSprite.setTexture(background);
float scale;
//I have tried several formula attempts, this is just my last attempt
if (windowSize.x >= windowSize.y) scale= (float)windowSize.x / background.getSize().x;
else scale = (float)windowSize.y / background.getSize().y;
backgroundSprite.setScale(scale, scale);
return backgroundSprite;
}
And this is how I call the functions:
bool mouseleftpressed;
sf::Vector2u windowSize(window.getSize());
//Background
sf::Texture background = setTexture("images/backgrounds/Grassy_Mountains_preview_fullcolor.png");
sf::Sprite backgroundImage = setBackground(windowSize, background);
sf::View backgroundView;
backgroundView.setSize(windowSize.x, windowSize.y);
backgroundView.setCenter(backgroundView.getSize().x / 2, backgroundView.getSize().y / 2);
backgroundView = getLetterboxView(backgroundView, windowSize);
//
while (window.pollEvent(event))
{
if (event.type == sf::Event::Closed) { mode = 3; };
if (sf::Mouse::isButtonPressed(sf::Mouse::Left))
{
mouseleftpressed = 1;
}
if (sf::Event::MouseButtonReleased && (mouseleftpressed == 1))
{
sf::Vector2i clickedco = sf::Mouse::getPosition(window);
mouseleftpressed = 0;
}
if (event.type == sf::Event::Resized)
{
windowSize.x = event.size.width;
windowSize.y = event.size.height;
sf::Sprite backgroundImage = setBackground(windowSize, background);
}
}
You guys have any ideas or a good tutorial link? Please remember I am a beginner in C++ and SFML.
