how can you change the make of a SFML interface?
#include <SFML/Graphics.hpp>
int main()
{
window.create(sf::VideoMode(800, 600), "The Veterans");
while (window.isOpen())
{
sf::Event event;
while (window.pollEvent(event))
{
if (event.type == sf::Event::Closed)
window.close();
}
window.display();
}
return 0;
}
I want Background to be red.
Now it's black.
If you want to change the background of a SFML window, you have to use sf::RenderWindow::clear with a argument for the color (No argument = Black background). The function call would be:
window.clear(sf::Color::Red);
This "clears" the window with a red color. Place the call right before the window.display().
If you want the window to display something you have to draw it to the screen. Whether that is drawing a shape or an image (or if you are using a RenderWindow, passing a color argument to the clear() method).
Related
I am working on a basic game in C++ using SFML for graphics. It is designed to use a grid system with functions to determine what should be displayed in each square. However, the compiler won't recognize the references to the window in the functions.
To keep it easier to expand there are functions for each type of terrain to be displayed, taking the coordinates as inputs (possibly not the correct term).
Good Question. SFML recommends that you create your window in the main function, but, if you want to modify it, you can simply pass it by reference. EX:
#include <SFML/Graphics.hpp>
void doSomething(sf::RenderWindow& window) {
sf::RectangleShape shape(sf::Vector2f(100, 100));
shape.setFillColor(sf::Color::Green);
shape.setPosition(50, 50);
window.draw(shape);
window.display();
}
int main() {
sf::RenderWindow window(sf::VideoMode(500, 500), "Test", sf::Style::Close);
while (window.isOpen()) {
sf::Event event;
while (window.pollEvent(event)) {
if (event.type == sf::Event::Closed) {
window.close();
}
}
window.clear(sf::Color::Black);
//draw here
doSomething(window);
}
return 0;
}
You should take a look at https://www.sfml-dev.org/tutorials/2.5/. Specifically I would look at https://www.sfml-dev.org/tutorials/2.5/window-window.php
Going through the SFML tutorial I tried to write a small code example that slides the window to the right over time, it acted in a way that I didn't expect (the window slid all the way to the bottom). Here's a minimal example that has the window moving despite sticking the exact same coordinates that getPosition spits out into setPosition
#include <SFML/Window.hpp>
#include <SFML/System/Clock.hpp>
#include <SFML/System/Time.hpp>
int main(){
sf::Window window(sf::VideoMode(800,600), "Aydin's Window");
window.setPosition(sf::Vector2i(10, 10));
sf::Clock clock;
while(window.isOpen()){
sf::Event event;
while(window.pollEvent(event)){
if(event.type == sf::Event::Closed)
window.close();
}
sf::Time elapsed = clock.getElapsedTime();
if(elapsed > sf::milliseconds(100)){
sf::Vector2i pos = window.getPosition();
window.setPosition(pos);
clock.restart();
}
}
return 0;
}
One would expect this code to keep the window where it is, but instead it slides to the right and downwards on my machine. I had a friend run the same code. On his machine it slides to the left and upwards. What is going on?
edit: when I create the window without decorations (sf::Style::None) the windows stays where it is. I'm guessing one of getPosition or setPosition is getting offset by the title bar and the other is not.
I am feeling really frustrated with draw() not working in my SFML project. My compiler gives off no errors, my eyes doesn't catch a thing that's off (as a reference I am using official tutorial). The problem is that when window load it doesn't draw a thing. It just stays a white window without any text in it.
Where could be the problem?
#include <SFML/Graphics.hpp>
int main() {
sf::RenderWindow window(sf::VideoMode(800,600), "Trying to make a game");
sf::Font font;
if (!font.loadFromFile("arial.ttf"))
{
//error
}
sf::Text text;
text.setFont(font);
text.setString("Hello, World!");
text.setCharacterSize(50);
text.setColor(sf::Color::Red);
text.setPosition(10, 50);
while (window.isOpen())
{
sf::Event event;
while (window.pollEvent(event))
{
if (event.type == sf::Event::Closed)
window.close();
}
}
window.clear();
window.draw(text);
window.display();
return 0;
}
You're closing the window before drawing the text...
I'm working on a project at the moment which is basically a visualisation of Sort algorithms to explain how they work (rather than an overview). I'm new to using the SFML (or even OpenGL) and have limited experience with the library, but what I'm trying to do is move the drawn sprite to different locations to show the sorting. I've looked over tutorials and examples, but they all take in keyboard input to move the sprite - something that isn't used in this project. Does anyone know exactly how to achieve this?
Here's the current code:
DrawCups.h
class DrawCups
{
public:
DrawCups(sf::RenderWindow& window);
~DrawCups();
void loadImage(const char* pathname, sf::Texture& texture, sf::Sprite& sprite);
void drawCup1();
private:
sf::RenderWindow& _window;
};
DrawCups.cpp (selected function)
void DrawCups::drawCup1()
{
// load our image
sf::Texture cup1; // the texture which will contain our pixel data
sf::Sprite cup1Sprite; // the sprite which will actually draw it
loadImage("./images/InsertionSort/red_cup_1.png", cup1, cup1Sprite);
cup1Sprite.setPosition(sf::Vector2f(150, 230));
_window.draw(cup1Sprite);
}
main.cpp
int main()
{
sf::RenderWindow window(sf::VideoMode(1366, 768), "Sorting Algorithm Visualisation: SFML");
window.setFramerateLimit(60);
while (window.isOpen())
{
sf::Event event;
while (window.pollEvent(event))
{
if (event.type == sf::Event::Closed)
window.close();
}
window.clear(sf::Color::White);
DrawCups drawToWindow(window);;
drawToWindow.drawCup1();
window.display();
}
return 0;
}
Create the image before the loop and update it before you draw it.
DrawCups drawToWindow(window); //Constructor creates the sprite
while (window.isOpen())
{
...
drawToWindow.update(); //Update the position
//Redraw
window.clear(sf::Color::White);
drawToWindow.drawCup1();
window.display();
}
I'm not sure what type of movement you want but the update function can be something like this:
void DrawCups::update()
{
sf::Vector2f pos = this->cup1Sprite.getPosition();
pos.x++; //Move 1 pixel to the left
this->cup1Sprite.setPosition(pos);
}
Obviously change the movement to suit your needs. Make smaller/larger updates if it's moving too fast or slow.
There are probably millions of these questions but, I can't get the coordinates of the mouse so that they line up with the program coordinate system, when the window is re-sized. I've tried mapPixelToCoords() and getting the mouse coordinates using sf::Event::MouseButton or sf::Mouse, but to no avail.
This problem is most likely from my incompetence, but I can't figure it out for the life of me. Also, I need to do this to change the coordinates of a rectangle, not detecting whether a box is being hovered over, if it was the answer would be a lot easier to figure out I feel.
Edit:
Source Code:
//Standard C++:
#include <iostream>
//SFML:
#include <SFML/Graphics.hpp>
int main()
{
sf::RenderWindow window(sf::VideoMode(800, 600), "Example");
sf::Event event;
sf::RectangleShape mousePoint;
mousePoint.setSize(sf::Vector2f(1, 1));
mousePoint.setFillColor(sf::Color::Red);
while (window.isOpen())
{
while (window.pollEvent(event))
{
if (event.type == sf::Event::Closed) //Close window
{
window.close();
return 0;
}
if (event.type == sf::Event::MouseButtonPressed)
{
if (event.mouseButton.button == sf::Mouse::Left)
{
//Get the mouse position:
sf::Vector2i mouse = sf::Mouse::getPosition(window);
//Map Pixel to Coords:
window.mapPixelToCoords(mouse);
//Set position of the mouse to the rectangle:
mousePoint.setPosition(mouse.x, mouse.y);
}
}
}
window.clear();
window.draw(mousePoint);
window.display();
}
}
After some doubt, I have uploaded some simple source code, which demonstrates my point. When you click the LMB, it moves the rectangle to where the program thinks the mouse is. When the screen hasn't been scaled, it is correctly calibrated, but when it is changed, the rectangle moves to a point which is no where near where the mouse is.
As shown in the official documentation and the official tutorial section of SFML, you can use the mapPixelToCoords function to map pixel/screen coordinates to world coordinates.
The signature of the function is as following:
Vector2f sf::RenderTarget::mapPixelToCoords(const Vector2i& point) const
As such the usage would look something like that:
//Get the mouse position:
sf::Vector2i mouse = sf::Mouse::getPosition(window);
//Map Pixel to Coords:
sf::Vecotr2f mouse_world = window.mapPixelToCoords(mouse);
//Set position of the mouse to the rectangle:
mousePoint.setPosition(mouse_world);
In other words, the mapPixelToCoords function, takes a const sf::Vector2i& as parameter and returns a sf::Vector2f and the original vector is not being modified.
It's always recommended to take a closer look at the documentation if something doesn't work as expected.