Hey so i'm making a pong game with SFML and in the process made a function that takes a Time, Speed, Angle of movement, buffer for the movement on the X axis, and buffer for the movement on the Y axis.

However i'm worried that giving the function the FrameTime() of the Window (the time since the frame was last updated) is not the best choice as the sprites might start jumping around if there's lag between frame updates or other problems.....

Hey so I'm making a pong game with SFML and in the process made a function that takes a Time, Speed, Angle of movement, buffer for the movement on the X axis, and buffer for the movement on the Y axis.

However I'm worried that giving the function the FrameTime() of the Window (the time since the frame was last updated) is not the best choice as the sprites might start jumping around if there's lag between frame updates or other problems.....

my Code:

#include<SFML/Graphics.hpp>
#include<SFML/System.hpp>
#include<cmath>
#include<vector>
#    define M_PI 3.14159265358979323846 

sf::RenderWindow Window;

template<typename T> 
void CalculateMove(T Time, T Speed, T Angle, T& buffX, T& buffY)
{   //determine what quadrant of circle we're in
    unsigned int  Quadrant= 1;
    if(Angle>90)  Quadrant= 2;
    if(Angle>180) Quadrant= 3;
    if(Angle>270) Quadrant= 4;

    //anything above 90 would be impossible triangle
    Angle= (float)(Angle-(int)Angle)+(float)((int)Angle%90); 

    // calculates x and y based on angle and Hypotenuse.02433
    if((int)Angle!=0){
        buffX= sin(Angle / 180 * M_PI)/ (1.f/(Speed*Time));
        buffY= sin((180-Angle-90)/ 180 * M_PI)/ (1.f/(Speed*Time));}
    
    else{// Movement is a straight line on X or Y axis
        if(Quadrant==0 || Quadrant==2) buffX= Speed*Time;
        if(Quadrant==1 || Quadrant==4) buffY= Speed*Time;}

    //Quadrant Factor (positive or negative movement on the axis)
    switch(Quadrant){
    case 1: break;
    case 2: buffX=-buffX; break;
    case 3: buffX=-buffX; buffY=-buffY; break;
    case 4: buffY=-buffY; break;}
};

/////////////////////////////////////////   Mysprite    ////////////////////////////////
class mySprite : public sf::Sprite
{
private:
    float velocity;
    float angle;

public:
    // all the values needed by the base class sprite();
    mySprite(
        const sf::Image& Img, 
        const sf::Vector2f& Position = sf::Vector2f(0, 0), 
        const sf::Vector2f& Scale = sf::Vector2f(1, 1), 
        float Rotation = 0.f, 
        const float Angle= 0.f, 
        const float Velocity= 0.f, 
        const sf::Color& Col = sf::Color(255, 255, 255, 255)):
      Sprite(Img, Position, Scale, Rotation, Col){
        angle= Angle;
        velocity= Velocity;};

    float Velocity(){return velocity;};
    void SetVelocity(float newVelocity){velocity=newVelocity;};
    float Angle(){return angle;};
    void SetAngle(float newAngle){angle=newAngle;};

    void Update(){ 
        float frameTime= Window.GetFrameTime();
        float X=0,Y=0;
        CalculateMove(frameTime,velocity,angle,X,Y);
        Move(X,-Y);
    };

    void Reflect(float CollAngle){
        SetRotation(-GetRotation());
        angle=-angle;
        //TODO: factor in the collision angle
    };
};

my UPDATED, WORKING Code:

   #include<SFML/Graphics.hpp>
#include<SFML/System.hpp>
#include<cmath>
#include<vector>
#    define M_PI 3.14159265358979323846 

sf::RenderWindow Window;

template<typename T> 
void CalculateMove(T Time, T Speed, T Angle, T& buffX, T& buffY)
{   //Make the degrees positive
    if(Angle<0) Angle= 360+Angle;
    //determine what quadrant of circle we're in
    unsigned int  Quadrant= 1;
    if(Angle>90)  Quadrant= 2;
    if(Angle>180) Quadrant= 3;
    if(Angle>270) Quadrant= 4;

    //anything above 90 would be impossible triangle
    Angle= (float)(Angle-(int)Angle)+(float)((int)Angle%90); 

    // calculates x and y based on angle and Hypotenuse
    if((int)Angle!=0){
        if(Quadrant==2 || Quadrant==4) Angle=90-Angle; //The unit circle triangle is flipped otherwise, causing x and y to be switched
        buffY= sin(Angle / 180 * M_PI)/ (1.f/(Speed*Time));  
        buffX= sin((180-Angle-90)/ 180 * M_PI)/ (1.f/(Speed*Time));}
    
    else{// Movement is a straight line on X or Y axis
        if(Quadrant==0 || Quadrant==2) buffX= Speed*Time;
        if(Quadrant==1 || Quadrant==4) buffY= Speed*Time;}

    //Quadrant Factor (positive or negative movement on the axis)
    switch(Quadrant){
    case 1: break;
    case 2: buffX=-buffX; break;
    case 3: buffX=-buffX; buffY=-buffY; break;
    case 4: buffY=-buffY; break;}
};

/////////////////////////////////////////   Mysprite    ////////////////////////////////
class mySprite : public sf::Sprite
{
private:
    float velocity;
    float angle;

public:
    // all the values needed by the base class sprite();
    mySprite(
        const sf::Image& Img, 
        const sf::Vector2f& Position = sf::Vector2f(0, 0), 
        const sf::Vector2f& Scale = sf::Vector2f(1, 1), 
        float Rotation = 0.f, 
        const float Angle= 0.f, 
        const float Velocity= 0.f, 
        const sf::Color& Col = sf::Color(255, 255, 255, 255)):
      Sprite(Img, Position, Scale, Rotation, Col){
        angle= Angle;
        velocity= Velocity;};

    float Velocity(){return velocity;};
    void SetVelocity(float newVelocity){velocity=newVelocity;};
    float Angle(){return angle;};
    void SetAngle(float newAngle){angle=(float)(newAngle-(int)newAngle)+(float)((int)newAngle%360);};

    void Update(){ 
        float frameTime= Window.GetFrameTime();
        float X=0,Y=0;
        SetRotation(angle);
        CalculateMove(frameTime,velocity,angle,X,Y);
        Move(X,-Y);
    };

    void Accelerate(float PPS){velocity+=PPS;};
    void Turn(float degrees){
        angle=(float)((angle+degrees)-(int)(angle+degrees))+(float)((int)(angle+degrees)%360);};

    void Reflect(float CollAngle){
        SetRotation(-GetRotation());
        angle=360-angle;
        //TODO: factor in the collision angle
    };
};