SFML object will only move at a small distance? - c++

i am new to SFML and was wandering why my player will only move at a certain distance witch is a very small distance.
Here is my code:
game.cpp:
#include <SFML/Graphics.hpp>
int main() {
sf::RenderWindow window(sf::VideoMode(800, 600), "SFML Game!");
while(window.isOpen()) {
sf::Event event;
while(window.pollEvent(event)) {
if(event.type == sf::Event::Closed)
window.close();
}
sf::Font font;
if(!font.loadFromFile("../resources/Lets Coffee.ttf"))
return EXIT_FAILURE;
sf::Text text("Use the WASD keys to move the player around", font, 20);
text.setPosition(5, 5);
// make a player sprite
sf::Texture *playerTexture;
playerTexture = new sf::Texture();
if(!playerTexture->loadFromFile("../resources/Bluey.png"))
return EXIT_FAILURE;
sf::RectangleShape player(sf::Vector2f(128, 128));
player.setPosition(400, 300);
player.setTexture(playerTexture);
player.setOutlineColor(sf::Color::Black);
player.setOutlineThickness(10);
// Here is my distance problem:
if(sf::Keyboard::isKeyPressed(sf::Keyboard::W)) {
player.move(0, -5);
}
if(sf::Keyboard::isKeyPressed(sf::Keyboard::S)) {
player.move(0, 5);
}
if(sf::Keyboard::isKeyPressed(sf::Keyboard::A)) {
player.move(-5, 0);
}
if(sf::Keyboard::isKeyPressed(sf::Keyboard::D)) {
player.move(5, 0);
}
window.clear();
window.draw(text);
window.draw(player);
window.display();
}
return 0;
}
Could any of you help?, and am i doing something wrong?, if i am the please tell me!

Credit : Gerard0097
The issue is that your are creating the player object within your main loop, so each cycle you create a new object and that's why is seems like it's moving a short distance but it's just different objects moving once and then being destroyed
Credit : Me
Just create player and texture before main loop (game loop) :
sf::RenderWindow window(sf::VideoMode(800, 600), "SFML Game!");
sf::Font font;
if(!font.loadFromFile("../resources/Lets Coffee.ttf"))
return EXIT_FAILURE;
sf::Text text("Use the WASD keys to move the player around", font, 20);
text.setPosition(5, 5);
sf::Texture *playerTexture;
playerTexture = new sf::Texture();
if(!playerTexture->loadFromFile("../resources/Bluey.png"))
return EXIT_FAILURE;
sf::RectangleShape player(sf::Vector2f(128, 128));
player.setPosition(400, 300);
player.setTexture(playerTexture);
player.setOutlineColor(sf::Color::Black);
player.setOutlineThickness(10);
and then your game loop :
while (game.isOpen) {
// Your Game Logic, Event Handling and drawings
}

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Second Example : Here the circle is scaled down towards the top left corner of its bounding box : this is the kind of behavior I want to achieve but using Transforms
#include &ltSFML/Graphics.hpp&gt
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note: this is a possible duplicate of Transformations igrnores sf::Sprite's origin , but the only answer to this thread is my own, and the solution I suggest is really not ideal.

SFML Pixel Perfect Collision limited to a view?

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... if both car and wall are related with the main window, I get a perfect car collision with the wall. (see image).
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Screenshot of offset in the window
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(2.3.1) Set scale of background texture to renderwindow size

Just started learning SFML (so please bear with me).
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The scale factor you need is simply the ratio between the window size and the texture size. sf::Texture has a getSize function, as has sf::RenderWindow. Simply get the sizes of both, calculate the ratio and use it to set the scale of the sprite, like this:
#include <SFML/Graphics.hpp>
#include <SFML/Window.hpp>
#include <iostream>
int main()
{
sf::RenderWindow window(sf::VideoMode(600, 300), "Simple Game");
sf::Texture BackgroundTexture;
sf::Sprite background;
sf::Vector2u TextureSize; //Added to store texture size.
sf::Vector2u WindowSize; //Added to store window size.
if(!BackgroundTexture.loadFromFile("background.png"))
{
return -1;
}
else
{
TextureSize = BackgroundTexture.getSize(); //Get size of texture.
WindowSize = window.getSize(); //Get size of window.
float ScaleX = (float) WindowSize.x / TextureSize.x;
float ScaleY = (float) WindowSize.y / TextureSize.y; //Calculate scale.
background.setTexture(BackgroundTexture);
background.setScale(ScaleX, ScaleY); //Set scale.
}
while(window.isOpen())
{
sf::Event event;
while(window.pollEvent(event))
{
switch(event.type)
{
case sf::Event::Closed:
window.close();
}
}
window.clear();
window.draw(background);
window.display();
}
}

How to draw on a single buffer for generative art purposes

I'm actually facing a issue I can't solve by myself, using SFML I have a single shape, and I'm moving it at each frame, and then I draw it. The problem is, SFML using two buffers, the trail won't be the same on each buffer (frame) and it will give a weird blinking effect.
I need your knowledge, should I find another way of doing it, like an array of shapes that I'll extend. Or is there a way to skip the second buffer? Making this buffer a piece of paper, and my shape the brush.
sf::CircleShape circle;
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window.display();
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May you spend a nice day.
you can achieve that by using sf::RenderTexture which acts as the back buffer (single buffer) to make your drawing and then draw it on screen via sf::RenderWindow`
#include <SFML/Graphics.hpp>
int main()
{
sf::RenderWindow window(sf::VideoMode(800, 600), "SFML art");
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if (!target.create(window.getSize().x, window.getSize().y))
return -1;
target.clear(sf::Color::White);
target.display();
while (window.isOpen())
{
sf::Event event;
while (window.pollEvent(event))
{
if (event.type == sf::Event::Closed)
window.close();
}
if (sf::Mouse::isButtonPressed(sf::Mouse::Left))
{
sf::CircleShape circle(5.f, 32u);
circle.setPosition(sf::Vector2f(sf::Mouse::getPosition(window)));
circle.setFillColor(sf::Color::Red);
target.draw(circle, sf::BlendNone);
target.display();
}
window.clear();
window.draw(sf::Sprite(target.getTexture()));
window.display();
}
}
The purpose of double buffering is to avoid showing parts of not fully rendered scene during rendering of a frame. So your problem has nothing to do with double-buffering itself. Basically, you need to generate all the primitives necessary to render a particular frame every time. In your specific case you could achieve this like this:
sf::CircleShape circle;
//Init the circle (radius etc)
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int frameCount = 0;
while(!done)
{
++frameCount;
for (int i = 0; i < frameCount; ++i) {
circle.setPosition(pos + sf::Vector2f(i, 0));
window.draw(circle);
}
window.display();
}