Following are the changes mentioned in bold in order to obtain the required result and stop scrolling in the background. #include \"SDL/SDL.h\" #include //The attributes of the screen can be defined as follows const int SCN_WIDTH = 640; const int SCN_HEIGHT = 480; const int SCN_BPP = 32; //BPP defines bits per pixel SDL_Surface* Background = NULL; SDL_Surface* SpriteImage = NULL; SDL_Surface* Backbuffer = NULL; int SpriteFrame = 0; int FrameCounter = 0; const int MaxSpriteFrame = 12; const int FrameDelay = 2; int BackgroundX = 0; SDL_Surface* LoadImage(char* fileName); bool LoadFiles(); void FreeFiles(); void DrawImage(SDL_Surface* image, SDL_Surface* destSurface, int x, int y); void DrawImageFrame(SDL_Surface* image, SDL_Surface* destSurface, int x, int y, int width, int height, int frame); bool ProgramIsRunning(); int main(int argc, char* args[]) { if(SDL_Init(SDL_INIT_EVERYTHING) < 0) { printf(\"Failed to initialize SDL!\ \"); return 0; } Backbuffer = SDL_SetVideoMode(800, 600, 32, SDL_SWSURFACE); SDL_WM_SetCaption(\"Image Animation\", NULL); if(!LoadFiles()) { printf(\"Failed to load all files!\ \"); FreeFiles(); SDL_Quit(); return 0; } while(ProgramIsRunning()) { //Update\'s the sprites frame FrameCounter++; if(FrameCounter > FrameDelay) { FrameCounter = 0; SpriteFrame++; } if(SpriteFrame > MaxSpriteFrame) SpriteFrame = 0; //Background scrolling can be removed from this position //Render the scene DrawImage(Background,Backbuffer, BackgroundX, 0); DrawImage(Background,Backbuffer, BackgroundX+800, 0); DrawImageFrame(SpriteImage, Backbuffer, 350,250, 150, 120, SpriteFrame); SDL_Delay(20); SDL_Flip(Backbuffer); } FreeFiles(); SDL_Quit(); return 0; } SDL_Surface* LoadImage(char* fileName) { SDL_Surface* imageLoaded = NULL; SDL_Surface* processedImage = NULL; imageLoaded = SDL_LoadBMP(fileName); if(imageLoaded != NULL) { processedImage = SDL_DisplayFormat(imageLoaded); SDL_FreeSurface(imageLoaded); if(processedImage != NULL) { //Here we map the color key Uint32 colorKey = SDL_MapRGB(processedImage->format, 0, 0xFF, 0xFF); //Now, set all the pixels of color R 0,G 0*FF,B 0*FF to be transparent SDL_SetColorKey(processedImage, SDL_SRCCOLORKEY, colorKey); } } return processedImage; } bool LoadFiles() { Background = LoadImage(\"graphics/background.bmp\"); if(Background == NULL) return false; SpriteImage = LoadImage(\"graphics/bat.bmp\"); //The file should be preloaded and linked with the required libraries in SDL if(SpriteImage == NULL) return false; else return true; } void FreeFiles() { SDL_FreeSurface(Background); SDL_FreeSurface(SpriteImage); } void DrawImage(SDL_Surface* image, SDL_Surface* destSurface, int x, int y) //A temporary rectangle is used to hold the offsets { SDL_Rect destRect; //Giving the offsets to the rectangle destRect.x = x; destRect.y = y; //Blit the surface SDL_BlitSurface(image, NULL, destSurface, &destRect); } //Here, we need to start the main function: int main(int argc,char** args) //Now, initialize all SDL subsystems if .

1. Following are the changes mentioned in bold in order to obtain the required result and stop
scrolling in the background.
#include "SDL/SDL.h"
#include
//The attributes of the screen can be defined as follows
const int SCN_WIDTH = 640;
const int SCN_HEIGHT = 480;
const int SCN_BPP = 32;
//BPP defines bits per pixel
SDL_Surface* Background = NULL;
SDL_Surface* SpriteImage = NULL;
SDL_Surface* Backbuffer = NULL;
int SpriteFrame = 0;
int FrameCounter = 0;
const int MaxSpriteFrame = 12;
const int FrameDelay = 2;
int BackgroundX = 0;
SDL_Surface* LoadImage(char* fileName);
bool LoadFiles();
void FreeFiles();
void DrawImage(SDL_Surface* image, SDL_Surface* destSurface, int x, int y);
void DrawImageFrame(SDL_Surface* image, SDL_Surface* destSurface, int x, int y, int width,
int height, int frame);
bool ProgramIsRunning();
int main(int argc, char* args[])
{
if(SDL_Init(SDL_INIT_EVERYTHING) < 0)
{
printf("Failed to initialize SDL! ");
return 0;
}
Backbuffer = SDL_SetVideoMode(800, 600, 32, SDL_SWSURFACE);
SDL_WM_SetCaption("Image Animation", NULL);
if(!LoadFiles())
{

2. printf("Failed to load all files! ");
FreeFiles();
SDL_Quit();
return 0;
}
while(ProgramIsRunning())
{
//Update's the sprites frame
FrameCounter++;
if(FrameCounter > FrameDelay)
{
FrameCounter = 0;
SpriteFrame++;
}
if(SpriteFrame > MaxSpriteFrame)
SpriteFrame = 0;
//Background scrolling can be removed from this position
//Render the scene
DrawImage(Background,Backbuffer, BackgroundX, 0);
DrawImage(Background,Backbuffer, BackgroundX+800, 0);
DrawImageFrame(SpriteImage, Backbuffer, 350,250, 150, 120, SpriteFrame);
SDL_Delay(20);
SDL_Flip(Backbuffer);
}
FreeFiles();
SDL_Quit();
return 0;
}
SDL_Surface* LoadImage(char* fileName)
{
SDL_Surface* imageLoaded = NULL;
SDL_Surface* processedImage = NULL;
imageLoaded = SDL_LoadBMP(fileName);
if(imageLoaded != NULL)
{
processedImage = SDL_DisplayFormat(imageLoaded);

3. SDL_FreeSurface(imageLoaded);
if(processedImage != NULL)
{
//Here we map the color key
Uint32 colorKey = SDL_MapRGB(processedImage->format, 0, 0xFF, 0xFF);
//Now, set all the pixels of color R 0,G 0*FF,B 0*FF to be transparent
SDL_SetColorKey(processedImage, SDL_SRCCOLORKEY, colorKey);
}
}
return processedImage;
}
bool LoadFiles()
{
Background = LoadImage("graphics/background.bmp");
if(Background == NULL)
return false;
SpriteImage = LoadImage("graphics/bat.bmp");
//The file should be preloaded and linked with the required libraries in SDL
if(SpriteImage == NULL)
return false;
else
return true;
}
void FreeFiles()
{
SDL_FreeSurface(Background);
SDL_FreeSurface(SpriteImage);
}
void DrawImage(SDL_Surface* image, SDL_Surface* destSurface, int x, int y)
//A temporary rectangle is used to hold the offsets
{
SDL_Rect destRect;
//Giving the offsets to the rectangle
destRect.x = x;
destRect.y = y;
//Blit the surface

4. SDL_BlitSurface(image, NULL, destSurface, &destRect);
}
//Here, we need to start the main function:
int main(int argc,char** args)
//Now, initialize all SDL subsystems
if (SDL_Init( SDL_INIT_EVERYTHING ) == -1)
{
return 1;
}
//SDL sysystems are things like video,timers,audio etc which are the individual engine
components used to
make a game
void DrawImageFrame(SDL_Surface* image, SDL_Surface* destSurface, int x, int y, int width,
int height, int frame)
{
SDL_Rect destRect;
destRect.x = x;
destRect.y = y;
int columns = image->w/width;
SDL_Rect sourceRect;
sourceRect.y = (frame/columns)*height;
sourceRect.x = (frame%columns)*width;
sourceRect.w = width;
sourceRect.h = height;
SDL_BlitSurface(image, &sourceRect, destSurface, &destRect);
}
bool ProgramIsRunning()
{
SDL_Event event;
bool running = true;
while(SDL_PollEvent(&event))
{
if(event.type == SDL_QUIT)
running = false;
}

5. return running;
}
Solution
Following are the changes mentioned in bold in order to obtain the required result and stop
scrolling in the background.
#include "SDL/SDL.h"
#include
//The attributes of the screen can be defined as follows
const int SCN_WIDTH = 640;
const int SCN_HEIGHT = 480;
const int SCN_BPP = 32;
//BPP defines bits per pixel
SDL_Surface* Background = NULL;
SDL_Surface* SpriteImage = NULL;
SDL_Surface* Backbuffer = NULL;
int SpriteFrame = 0;
int FrameCounter = 0;
const int MaxSpriteFrame = 12;
const int FrameDelay = 2;
int BackgroundX = 0;
SDL_Surface* LoadImage(char* fileName);
bool LoadFiles();
void FreeFiles();
void DrawImage(SDL_Surface* image, SDL_Surface* destSurface, int x, int y);
void DrawImageFrame(SDL_Surface* image, SDL_Surface* destSurface, int x, int y, int width,
int height, int frame);
bool ProgramIsRunning();
int main(int argc, char* args[])
{
if(SDL_Init(SDL_INIT_EVERYTHING) < 0)
{
printf("Failed to initialize SDL! ");
return 0;
}

6. Backbuffer = SDL_SetVideoMode(800, 600, 32, SDL_SWSURFACE);
SDL_WM_SetCaption("Image Animation", NULL);
if(!LoadFiles())
{
printf("Failed to load all files! ");
FreeFiles();
SDL_Quit();
return 0;
}
while(ProgramIsRunning())
{
//Update's the sprites frame
FrameCounter++;
if(FrameCounter > FrameDelay)
{
FrameCounter = 0;
SpriteFrame++;
}
if(SpriteFrame > MaxSpriteFrame)
SpriteFrame = 0;
//Background scrolling can be removed from this position
//Render the scene
DrawImage(Background,Backbuffer, BackgroundX, 0);
DrawImage(Background,Backbuffer, BackgroundX+800, 0);
DrawImageFrame(SpriteImage, Backbuffer, 350,250, 150, 120, SpriteFrame);
SDL_Delay(20);
SDL_Flip(Backbuffer);
}
FreeFiles();
SDL_Quit();
return 0;
}
SDL_Surface* LoadImage(char* fileName)
{
SDL_Surface* imageLoaded = NULL;
SDL_Surface* processedImage = NULL;

7. imageLoaded = SDL_LoadBMP(fileName);
if(imageLoaded != NULL)
{
processedImage = SDL_DisplayFormat(imageLoaded);
SDL_FreeSurface(imageLoaded);
if(processedImage != NULL)
{
//Here we map the color key
Uint32 colorKey = SDL_MapRGB(processedImage->format, 0, 0xFF, 0xFF);
//Now, set all the pixels of color R 0,G 0*FF,B 0*FF to be transparent
SDL_SetColorKey(processedImage, SDL_SRCCOLORKEY, colorKey);
}
}
return processedImage;
}
bool LoadFiles()
{
Background = LoadImage("graphics/background.bmp");
if(Background == NULL)
return false;
SpriteImage = LoadImage("graphics/bat.bmp");
//The file should be preloaded and linked with the required libraries in SDL
if(SpriteImage == NULL)
return false;
else
return true;
}
void FreeFiles()
{
SDL_FreeSurface(Background);
SDL_FreeSurface(SpriteImage);
}
void DrawImage(SDL_Surface* image, SDL_Surface* destSurface, int x, int y)
//A temporary rectangle is used to hold the offsets
{
SDL_Rect destRect;

8. //Giving the offsets to the rectangle
destRect.x = x;
destRect.y = y;
//Blit the surface
SDL_BlitSurface(image, NULL, destSurface, &destRect);
}
//Here, we need to start the main function:
int main(int argc,char** args)
//Now, initialize all SDL subsystems
if (SDL_Init( SDL_INIT_EVERYTHING ) == -1)
{
return 1;
}
//SDL sysystems are things like video,timers,audio etc which are the individual engine
components used to
make a game
void DrawImageFrame(SDL_Surface* image, SDL_Surface* destSurface, int x, int y, int width,
int height, int frame)
{
SDL_Rect destRect;
destRect.x = x;
destRect.y = y;
int columns = image->w/width;
SDL_Rect sourceRect;
sourceRect.y = (frame/columns)*height;
sourceRect.x = (frame%columns)*width;
sourceRect.w = width;
sourceRect.h = height;
SDL_BlitSurface(image, &sourceRect, destSurface, &destRect);
}
bool ProgramIsRunning()
{
SDL_Event event;
bool running = true;
while(SDL_PollEvent(&event))

9. {
if(event.type == SDL_QUIT)
running = false;
}
return running;
}