Moving a sprite and handling events - c++

Question

I'm learning the SFML library at the moment but I'm a little lost on moving the sprite. Here's my main.cpp file:
#include <SFML/Graphics.hpp>
int main()
{
// Create the main window
sf::RenderWindow App(sf::VideoMode(800, 600), "SFML window");
// Load a sprite to display
sf::Texture Image;
if (!Image.LoadFromFile("cb.bmp"))
return EXIT_FAILURE;
sf::Sprite Sprite(Image);
// Define the spead of the sprite
float spriteSpeed = 10.f;
// Start the game loop
while (App.IsOpened())
{
// Process events
sf::Event Event;
while (App.PollEvent(Event))
{
// Close window : exit
if (Event.Type == sf::Event::Closed)
App.Close();
if (sf::Keyboard::IsKeyPressed(sf::Keyboard::Up))
Sprite.Move(spriteSpeed * App.GetFrameTime(), 0);
}
// Clear screen
App.Clear();
// Draw the sprite
App.Draw(Sprite);
// Update the window
App.Display();
}
return EXIT_SUCCESS;
}
But I get really slow, inconsistent movements, why isn't the sprite moving steadily around the screen? Also, seeing as how I plan to use the mouse to control the character how will I use the loop to make the character move towards where the user clicks?

Answer 1

You shouldn't be checking if the key is held down in the event loop.
SFML only posts one event when the key is first pressed down, and then another event when the key is released. In this case, your code is only checking if the key is held when an event occurs (such as moving your mouse, clicking, or anything else).
Moving the IsKeyPressed check out of the event loop, preferably below it, should fix the issue.
Making the sprite move towards your mouse is a more complicated issue, better suited for the Game Development StackExchange.