Проблемы рендеринга, одиночный эффект буферизации

Ситуация: В настоящее время я пытаюсь сделать несколько вещей (изображения и текст), используя SDL_image и SDL в C ++. Однако я сталкиваюсь с некоторыми проблемами, которые выглядят как проблемы с буферизацией, однако, с моими попытками исправить это, я застрял в течение нескольких часов безрезультатно.

Проблема: При рендеринге экран дает эффект одиночной буферизации, когда изображение в его предыдущей позиции все еще отображается на экране, как в последнем буфере. Я подозреваю, что проблема лежит где-то в моей функции рисования (функция основного цикла)

проблема http://oi41.tinypic.com/28v6gc0.jpg

Вот мой main.cpp:

#include "SDL.h"#include "SDL_image.h"#include "Player.h"#include "Values.h"#include <string>
#include <sstream>
#include "SDL_ttf.h"#include "Timer.h"

//The surfaces that will be used
SDL_Surface *message = NULL;
SDL_Surface *background = NULL;
SDL_Surface *text = NULL;
SDL_Surface *screen = NULL;
SDL_Surface *startStop = NULL;
SDL_Surface *pauseMessage = NULL;
SDL_Surface *seconds = NULL;
//The font thats going to be used
TTF_Font *font = NULL;
//The colour of the font
SDL_Color textColor = {255,255,255};

Player ** player;

Timer myTimer;

bool quit = false;
Uint32 start = 0;
bool running = true;

int fame = 0;
bool cap = true;
//Timer fps;

SDL_Event event;

void clean_up()
{
//Free the surfaces
//SDL_FreeSurface( message );
player[0]->clean();
SDL_FreeSurface( background );
SDL_FreeSurface( seconds );
SDL_FreeSurface(startStop);
SDL_FreeSurface(pauseMessage);
TTF_CloseFont(font);
TTF_Quit();
//Quit SDL
SDL_Quit();
}

SDL_Surface *load_image( std::string filename )
{
//Temporary storage for the image that's loaded
SDL_Surface* loadedImage = NULL;

//The optimized image that will be used
SDL_Surface* optimizedImage = NULL;

//Load the image
loadedImage = SDL_LoadBMP( filename.c_str() );

//If nothing went wrong in loading the image
if( loadedImage != NULL )
{
//Create an optimized image
optimizedImage = SDL_DisplayFormat( loadedImage );

//Free the old image
SDL_FreeSurface( loadedImage );
}

//Return the optimized image
return optimizedImage;
}

void apply_surface( int x, int y, SDL_Surface* source, SDL_Surface* destination )
{
//Make a temporary rectangle to hold the offsets
SDL_Rect offset;

//Give the offsets to the rectangle
offset.x = x;
offset.y = y;

//Blit the surface
SDL_BlitSurface( source, NULL, destination, &offset );
}

bool loadFiles()
{
player[0]->load_files();
background = load_image( "Floor1.bmp" );

//Open the font
font = TTF_OpenFont("lazy.ttf",28);

//If there was a problem in loadin the font
if(font == NULL)
{
return false;
}
return true;
}

bool init()
{
//Initialize all SDL subsystems
SDL_Init( SDL_INIT_EVERYTHING );

//Set up the screen
//screen = SDL_SetVideoMode( SCREEN_WIDTH, SCREEN_HEIGHT, SCREEN_BPP, SDL_SWSURFACE );
screen = SDL_SetVideoMode( SCREEN_WIDTH, SCREEN_HEIGHT, 0,
SDL_HWSURFACE | SDL_DOUBLEBUF );
//Initialize SDL_tff
if(TTF_Init() == -1)
{
return false;
}

//Set the window caption
SDL_WM_SetCaption( "10 seconds", NULL );

player = new Player*[1];
player[0] = new Player(screen);
loadFiles();return true;
};

void mainloop()
{
startStop = TTF_RenderText_Solid(font, "Press S to start or stop the timer", textColor);
pauseMessage = TTF_RenderText_Solid(font, "Press P to pause or unpause the timer", textColor);

myTimer.start();
while (quit == false)
{
//While there's events to handle
while( SDL_PollEvent( &event ) )
{
//Handle events for the dot
player[0]->handleInput(event);

if (event.type == SDL_KEYDOWN)
{
//if s was pressed
if(event.key.keysym.sym == SDLK_s)
{
//if the timer is running
if(myTimer.isStarted() == true)
{
//Stop the timer
myTimer.stop();
}
else
{
//Start the timer
myTimer.start();
}
}
if (event.key.keysym.sym == SDLK_p)
{
//If the timer is paused
if (myTimer.isPaused() == true)
{
//Unpause the timer
myTimer.unpause();
}
else
{
//Pause the timer
myTimer.pause();
}
}
}
//If the user has Xed out the window
else if( event.type == SDL_QUIT )
{
//Quit the program
quit = true;
}

}

//Apply all images to screen
apply_surface( 0, 0, background, screen );
apply_surface( ( SCREEN_WIDTH - startStop->w ) / 2, 200, startStop, screen );
apply_surface( ( SCREEN_WIDTH - pauseMessage->w ) / 2, 250, pauseMessage, screen );
//The timers time as a string
std::stringstream time;
//convert the timers time to a string
time << "Timer: " << myTimer.getTicks() / 1000.f;
seconds = TTF_RenderText_Solid( font, time.str().c_str(), textColor );
//Render the time surface
apply_surface( ( SCREEN_WIDTH - seconds->w ) / 2, 0, seconds, screen );
/Free the time surface

//PlayerHandling
player[0]->move();
player[0]->setCamera();
player[0]->draw();
SDL_FreeSurface( seconds );

SDL_Flip(screen);
}
}int main( int argc, char* args[] )
{

init();
mainloop();
clean_up();

return 0;
}