SDL Errors

I have started using SDL and am having trouble. Please bear in mind I AM ONLY 13.
I have this code:

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#include <SDL/SDL.h>
#include <SDL/SDL_image.h>
#include <string>

//Screen attributes
const int SCREEN_WIDTH = 640;
const int SCREEN_HEIGHT = 480;
const int SCREEN_BPP = 32;

//The surfaces
SDL_Surface *sprite = NULL;
SDL_Surface *background = NULL;
SDL_Surface *screen = NULL;

//The event structure that will be used
SDL_Event event;

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

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

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

    //If the image loaded
    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 )
{
    //Temporary rectangle to hold the offsets
    SDL_Rect offset;

    //Get the offsets
    offset.x = x;
    offset.y = y;

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

bool init()
{
    //Initialize all SDL subsystems
    if( SDL_Init( SDL_INIT_EVERYTHING ) == -1 )
    {
        return false;
    }

    //Set up the screen
    screen = SDL_SetVideoMode( SCREEN_WIDTH, SCREEN_HEIGHT, SCREEN_BPP, SDL_SWSURFACE );

    //If there was an error in setting up the screen
    if( screen == NULL )
    {
        return false;
    }

    //Set the window caption
    SDL_WM_SetCaption( "Platform Game", NULL );

    //If everything initialized fine
    return true;
}

bool load_files()
{
    //Load the image
    sprite = load_image( "sprite.png" );
    background = load_image( "background.png" );

    //If there was an error in loading the image
    if( sprite == NULL )
    {
        return false;
    }

    //If everything loaded fine
    return true;
}

void clean_up()
{
    //Free the surface
    SDL_FreeSurface( sprite );
    SDL_FreeSurface( background );

    //Quit SDL
    SDL_Quit();
}

class Sprite
{
      private:
      //The initial offsets
      int x, y;
      
      //The velocity of the sprite
      int xVel, yVel;
      
      public:
      //Initialize the variables
      Sprite();
      
      //Handles key presses
      void handle_input();
      
      //Move the sprite
      void move();
      
      //Show the sprite
      void show();
};

Sprite::Sprite()
{
      //Initialisze the offests
      x = 0;
      y = 470;
      
      //Initialize velocity
      xVel = 0;
      yVel = 0;
}

void Sprite::handle_input()
{
     //If a key was pressed
     if( event.type == SDL_KEYDOWN ) 
     { 
         //Adjust the velocity switch
         ( event.key.keysym.sym ) ;
           { 
              case SDLK_UP: yVel -= SPRITE_HEIGHT / 2; break; 
              case SDLK_DOWN: yVel += SPRITE_HEIGHT / 2; break; 
              case SDLK_LEFT: xVel -= SPRITE_WIDTH / 2; break; 
              case SDLK_RIGHT: xVel += SPRITE_WIDTH / 2; break; 
           } 
     }
     //If a key was released 
     else if( event.type == SDL_KEYUP ) 
     { 
          //Adjust the velocity 
          switch( event.key.keysym.sym ) 
          { 
                  case SDLK_UP: yVel += SPRITE_HEIGHT / 2; break; 
                  case SDLK_DOWN: yVel -= SPRITE_HEIGHT / 2;break; 
                  case SDLK_LEFT: xVel += SPRITE_WIDTH / 2; break; 
                  case SDLK_RIGHT: xVel -= SPRITE_WIDTH / 2; break; 
          }
     }  
}

void Sprite::move()
{
     //Move the sprite left or right
     x += xVel;
     
     //If the sprite moves to far left or right
     if( ( x < 0 ) || ( x + SPRITE_WIDTH > SCREEN_WIDTH ) ) 
     { 
         //move back 
         x -= xVel; 
     } 
     //Move the sprite up or down 
     y += yVel; 
     //If the sprite went too far up or down 
     if( ( y < 0 ) || ( y + SPRITE_HEIGHT > SCREEN_HEIGHT ) ) 
     {
         //move back 
         y -= yVel; 
     } 
}

void Sprite::show()
{
     //Show the sprite
     apply_surface(x, y, sprite, screen);
}

int main( int argc, char* args[] )
{
    //Make sure the program waits for a quit
    bool quit = false;

    //Initialize
    if( init() == false )
    {
        return 1;
    }

    //Load the files
    if( load_files() == false )
    {
        return 1;
    }

    //Apply the surface to the screen
    apply_surface( 0, 0, background, screen );

    //While the user hasn't quit
    while( quit == false )
    {
        //While there's an event to handle
        while( SDL_PollEvent( &event ) )
        {
            //Handle events for the Sprite 
            mySprite.handle_input();    
               
            //If the user has Xed out the window
            if( event.type == SDL_QUIT )
            {
                //Quit the program
                quit = true;
            }
        }
        
        //Move the sprite
        mySprite.move();
        
        //Show the dot
        mySprite.show();
       
        //Update the screen
        if( SDL_Flip( screen ) == -1 )
        {
            return 1;
        } 
        
        //Cap the frame rate
        if( fps.get_ticks() < 1000 / FRAMES_PER_SECOND )
        {
            SDL_Delay( ( 1000 / FRAMES_PER_SECOND ) - fps.get_ticks() );
        }      
    }            

    //Free the surface and quit SDL
    clean_up();

    return 0;
}


and these errors:

C:\Documents and Settings\Timbo\My Documents\C++\SDL\Platform Game\main.cpp In member function `void Sprite::handle_input()':
148 C:\Documents and Settings\Timbo\My Documents\C++\SDL\Platform Game\main.cpp case label ` SDLK_UP' not within a switch statement
148 C:\Documents and Settings\Timbo\My Documents\C++\SDL\Platform Game\main.cpp `SPRITE_HEIGHT' undeclared (first use this function)
148 C:\Documents and Settings\Timbo\My Documents\C++\SDL\Platform Game\main.cpp break statement not within loop or switch
149 C:\Documents and Settings\Timbo\My Documents\C++\SDL\Platform Game\main.cpp case label ` SDLK_DOWN' not within a switch statement
150 C:\Documents and Settings\Timbo\My Documents\C++\SDL\Platform Game\main.cpp break statement not within loop or switch
151 C:\Documents and Settings\Timbo\My Documents\C++\SDL\Platform Game\main.cpp case label ` SDLK_RIGHT' not within a switch statement
151 C:\Documents and Settings\Timbo\My Documents\C++\SDL\Platform Game\main.cpp break statement not within loop or switch
C:\Documents and Settings\Timbo\My Documents\C++\SDL\Platform Game\main.cpp In member function `void Sprite::move()':
174 C:\Documents and Settings\Timbo\My Documents\C++\SDL\Platform Game\main.cpp `SPRITE_WIDTH' undeclared (first use this function)
182 C:\Documents and Settings\Timbo\My Documents\C++\SDL\Platform Game\main.cpp `SPRITE_HEIGHT' undeclared (first use this function)
C:\Documents and Settings\Timbo\My Documents\C++\SDL\Platform Game\main.cpp In function `int SDL_main(int, char**)':
222 C:\Documents and Settings\Timbo\My Documents\C++\SDL\Platform Game\main.cpp `mySprite' undeclared (first use this function)
236 C:\Documents and Settings\Timbo\My Documents\C++\SDL\Platform Game\main.cpp `mySprite' undeclared (first use this function)
245 C:\Documents and Settings\Timbo\My Documents\C++\SDL\Platform Game\main.cpp `fps' undeclared (first use this function)
245 C:\Documents and Settings\Timbo\My Documents\C++\SDL\Platform Game\main.cpp `FRAMES_PER_SECOND' undeclared (first use this function)
1. you missed 'switch' on line 146
2. there are no such variables as SPRITE_HEIGHT and SPRITE_WIDTH
3. mySprite is not declared (line 222)
4. fps is not declared
5. FRAMES_PER_SECOND undeclared

those variables won't declare themselves!

note, how I only told you what the errors said.
Last edited on
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