Transforming a vector using SFML, e.g. by rotating it by 45 degree.

rotate.cpp

#include <SFML/Graphics/Transform.hpp>
#include <SFML/System/Vector2.hpp>
#include <iostream>

int main() {
  // First we'll need a vector to tranform
  sf::Vector2f myVector(2, 0);
  std::cout << "myVector: " << myVector.x << ", " << myVector.y << "\n";

  // Then the actual transform
  sf::Transform myTransform;
  myTransform.rotate(45); // Rotate by 45 degree

  // Now calculate and output the resulting vector
  sf::Vector2f myTransformedVector = myTransform.transformPoint(myVector);
  std::cout << "myTransformedVector: " << myTransformedVector.x << ", " << myTransformedVector.y << "\n";

  return 0;
}