#include <SDL.h>
#include <string>
 
SDL_Surface* buffer = NULL;
SDL_Surface* background = NULL;
SDL_Surface* dot = NULL;
 
SDL_Event event;
 
SDL_Rect offset;
 
int dx = 0;
int dy = 0;
 
int main(int argc, char* args[])
{
    SDL_Init(SDL_INIT_EVERYTHING);
 
    buffer = SDL_SetVideoMode(640, 480, 32, SDL_SWSURFACE);
 
    background = SDL_LoadBMP("background.bmp");
    dot = SDL_LoadBMP("dot.bmp");
 
    offset.x = 300;
    offset.y = 200;

 
    int x = 0;
    int y = 0;

    // This is our target-position variables. Initialize it to the current location
    int toX = offset.x;
    int toY = offset.y;
 
    Uint8 *key = SDL_GetKeyState( NULL );
 
    while (event.type != SDL_QUIT)
    {
        if( event.type == SDL_MOUSEMOTION )
        {
            //Get the mouse offsets
            x = event.motion.x;
            y = event.motion.y;
        }
        if( event.type == SDL_MOUSEBUTTONDOWN )
        {
            // The button has been pressed.
            if( event.button.button == SDL_BUTTON_LEFT )
            {
                // We need to set our target x and y location as the current mouse location. We need to store this as seperate variables. 
                // Think what would happen if we just used the x and y, and we wanted to check if we had reached the target location (which would then keep moving with the mouse)
                toX = x;
                toY = Y;

                dx = toX - offset.x;
                dy = toY - offset.y;
            }
        }

        // If we are not currently at the target location we need to move towards it
        if (offset.x != toX || offset.y != toY)
        {
            
            offset.x += dx / 20;
            offset.y += dy / 20;    
      }
 
        SDL_BlitSurface(background, NULL, buffer, NULL);
        SDL_BlitSurface(dot, NULL, buffer, &offset);
        SDL_PollEvent(&event);
        SDL_Flip(buffer);
    }
 
    SDL_FreeSurface(background);
    SDL_FreeSurface(dot);
    SDL_Quit();
    return 0;
}