SDL simple game change level

[jefw123]

Hey guys,


have been learning c++ for about half a year and have decided to create a simple 2d game using the SDL library. Although the code is pretty messy and not really structured into classes, I have been able to create an extremely simple box game where you have to get to the end of the level and can touch other blocks to apply certain attributes to yourself, such as going smaller or bigger. I have also added a collision engine and simple sounds which change when you change size. My only issue is that when I reach the end of the level and touch the block I am not sure how to delete all of the previous rectangles and draw on new one's to symbolize a new level.

Here is my code, but it is quite messy:

#include "SDL/SDL.h"
#include "SDL/SDL_mixer.h"


//collision engine function
bool collision(SDL_Rect* rect1, SDL_Rect* rect2)
{
    if(rect1->y >= rect2-> y + rect2->h)
      return false;
    if(rect1->x >= rect2->x + rect2->w)
    return false;

   if(rect1->y + rect1->h <= rect2->y)
   return false;
   if(rect1->x + rect1->w <= rect2->x)
   return false;

  return true;
}



int main(int argc, char* argv[])
{

//initialise SDL
SDL_Init(SDL_INIT_EVERYTHING);

//initialise screen surface
SDL_Surface *screen;

Mix_Music* music;
Mix_Music* music2;
Mix_Music* music3;

Mix_OpenAudio(22050,MIX_DEFAULT_FORMAT,2,4096);

music = Mix_LoadMUS("atmospace_jungle.wav");
music2 = Mix_LoadMUS("partytrain.wav");
music3 = Mix_LoadMUS("lost_in_euroland.wav");

Mix_PlayMusic(music,-1);





//set screen attributes (res,bpp etc.)
screen = SDL_SetVideoMode(640,480,32,SDL_SWSURFACE);


//set name of program in top right corner
SDL_WM_SetCaption("Block Maze", NULL);

//set running to true
bool running = true;


  //states of the player sorted by size
  bool normal = true;
  bool shrunk = false;
  bool huge = false;


  //set game FPS
  int FPS = 90;

//set 'start' to an integer
  Uint32 start;

//bool variable for whether or not a key is pressed
bool b[7] = {0,0,0,0,0,0,0};

bool destroyed[2] = {1,0};


//rectangle position and size for the player
  SDL_Rect rect;
  rect.x = 10;
  rect.y = 10;
  rect.w = 20;
  rect.h = 20;


 //position and size for the block which shrinks the player
  SDL_Rect shrinkblock;
  shrinkblock.x = 20;
  shrinkblock.y = 110;
  shrinkblock.w = 20;
  shrinkblock.h = 20;

//position and size for the invisible line which makes the player bigger
  SDL_Rect enlargeblock;
  enlargeblock.x = 300;
  enlargeblock.y = 200;
  enlargeblock.w = 10;
  enlargeblock.h = 50;

//position and size for the block that enlarges the player 10x10
  SDL_Rect supersize;
  supersize.x = 20;
  supersize.y = 215;
  supersize.w = 20;
  supersize.h = 20;

//size and position for the wall that cannot be passed unless the player is super size
  SDL_Rect destructiblewall;
  destructiblewall.x = 600;
  destructiblewall.y = 250;
  destructiblewall.w = 39;
  destructiblewall.h = 50;


//array to hold the normal white blocks in the game
  SDL_Rect rectarray[6];

//block arrays
  rectarray[0] = {0,40, 600, 50};
  rectarray[1] = {550, 150, 140, 50};
  rectarray[2] = {0, 150, 539, 50};
  rectarray[3] = {0, 250, 600, 50};
  rectarray[4] = {639,250,1,50};
  rectarray[5] = {50, 315, 590, 50};

  bool changesong[1] = {0};








//black -> screen
  Uint32 color = SDL_MapRGB(screen->format,0x00,0x00,0x00);

//white -> white walls
  Uint32 color2 = SDL_MapRGB(screen->format,0xFF,0xFF,0xFF);

//Dark Red -> player
Uint32 color3 = SDL_MapRGB(screen->format,125,40,60);

//random purple -> shrink block
Uint32 color4 = SDL_MapRGB(screen->format,150,25,225);

//Light green -> destructive wall
Uint32 color5 = SDL_MapRGB(screen->format,150,255,100);

//Dark blue -> super size block
Uint32 color6 = SDL_MapRGB(screen->format,10,2,100);

Uint32 color7 = SDL_MapRGB(screen->format,150,0,0);





//for loop display the walls on the screen
  for(int i = 0; i < 6; i++){
  SDL_FillRect(screen,&rectarray[i],color2);
  }



//start of game loop
  while(running)
  {

      //start is equal to the time
      start = SDL_GetTicks();

      //name event
      SDL_Event event;

      if(changesong[0])
      {

          changesong[0] = 0;

  if(normal)
      Mix_PlayMusic(music,-1);

      if(shrunk)
      Mix_PlayMusic(music2,-1);

      if(huge)
      Mix_PlayMusic(music3,-1);
      }



      //while there is an event to handle
      while(SDL_PollEvent(&event))
      {

          //switch event types
          switch(event.type)
          {

              //if quit is pressed
              case SDL_QUIT:
                //set running to false -> exits game loop
              running = false;
              break;


            //if a key is pressed
            case SDL_KEYDOWN:
            switch(event.key.keysym.sym)
            {

                //if up set b[0] to true
                case SDLK_UP:
                b[0] = 1;
                break;

                //if left set b[1] to true
                case SDLK_LEFT:
                b[1] = 1;
                break;

                //if down set b[2] to true
                case SDLK_DOWN:
                b[2] = 1;
                break;

                //if right set b[3] to true
                case SDLK_RIGHT:
                b[3] = 1;
                break;

                //if r set b[4] to true
                case SDLK_r:
                b[4] = 1;
                break;

                //if f set b[5] to true
                case SDLK_f:
                b[5] = 1;
                break;

                case SDLK_h:
                b[6] = 1;
                break;



            }
            break;


         //when a key is un-pressed set the keys to false
        case SDL_KEYUP:
        switch(event.key.keysym.sym)
        {
              case SDLK_UP:
                b[0] = 0;
                break;

                case SDLK_LEFT:
                b[1] = 0;
                break;

                case SDLK_DOWN:
                b[2] = 0;
                break;

                case SDLK_RIGHT:
                b[3] = 0;
                break;

                case SDLK_r:
                b[4] = 0;
                break;

                 case SDLK_f:
                b[5] = 0;
                break;

                case SDLK_h:
                b[6] = 0;
                break;


        }
        break;


          }


      }


 

Thanks for all your help and sorry but, due to the word count, i had to split the code in half :(

[jefw123]

    


      //make the player the native color
      SDL_FillRect(screen,&rect,color);







    //if up is held down
    if(b[0])
    {

       //move square up
        rect.y--;
       //check for collision
          for(int i = 0; i < 6; i++)
          if(collision(&rect,&rectarray[i]))
          rect.y++;


        //if collision with the shrink block
        if(collision(&rect,&shrinkblock))
          {
              rect.y++;

              //if the player is of normal size, shrink him/her
              if(normal)
              {

             rect.w -= 10;
             rect.h -= 10;
             normal = 0;
             shrunk = 1;
             changesong[0] = 1;
              }

          }


        //if collision with the enlargeblock
        if(collision(&rect,&enlargeblock))
{

            //if player is small, make them bigger
              if(shrunk)
              {
                  if(rect.y >= 225)
                  {
                      rect.y = 220;
                  }
                  rect.w += 10;
             rect.h += 10;
             shrunk = 0;
             normal = 1;

              changesong[0] = 1;



              }

}

   //if collision with the super size block
   if(collision(&rect,&supersize))
   {
       rect.y++;

       //if the player is of normal size, make them bigger else leave the same
       if(normal)
       {
           if(rect.y >= 220)
                  {
                      rect.y = 215;
                  }
           rect.w += 10;
           rect.h += 10;
           normal = 0;
           huge = 1;

            changesong[0] = 1;
       }
   }

   //if collision with destructible wall

      if(collision(&rect,&destructiblewall))
   {

       //if player is normal or shrunk, dont let them pass
       if((normal) || (shrunk))
       if(destroyed[0])
       rect.y++;

         else if(huge)
       {
           destroyed[0] = 0;
           destroyed[1] = 1;
       }

   }


        else if (rect.y <= -1 )
        rect.y++;

    }

    if(b[1])
    {
          rect.x--;
          for(int i = 0; i < 6; i++)
          if(collision(&rect,&rectarray[i]))
          rect.x++;

       if(collision(&rect,&shrinkblock))
       {
           rect.x++;
           if(normal)
           {

             rect.w -= 10;
             rect.h -= 10;
             normal = 0;
             shrunk = 1;

             changesong[0] = 1;
           }



         }

                 if(collision(&rect,&enlargeblock))
{
 if(shrunk)
              {

                  if(rect.y >= 225)
                  {
                      rect.y = 220;
                  }
                  rect.w += 10;
             rect.h += 10;
             shrunk = 0;
             normal = 1;
              changesong[0] = 1;
              }
}

   if(collision(&rect,&supersize))
   {
       rect.x++;
       if(normal)
       {
           if(rect.y >= 220)
                  {
                      rect.y = 215;
                  }
           rect.w += 10;
           rect.h += 10;
           normal = 0;
           huge = 1;
            changesong[0] = 1;
       }
   }
      if(collision(&rect,&destructiblewall))
   {
       if((normal) || (shrunk))
       if(destroyed[0])
       rect.x++;

         else if(huge)
       {
           destroyed[0] = 0;
           destroyed[1]= 1;
       }

   }

        else if(rect.x <= -1 )
        rect.x++;

    }

    if(b[2])
    {
         rect.y++;


       for(int i = 0; i < 6; i++)
          if(collision(&rect,&rectarray[i]))
          rect.y--;

         if(collision(&rect,&shrinkblock))
         {
                rect.y--;
             if(normal)
             {

             rect.w -= 10;
             rect.h -= 10;
             normal = 0;
             shrunk = 1;

             changesong[0] = 1;

         }
         }

            if(collision(&rect,&enlargeblock))
{

            if(shrunk)
              {
                  if(rect.y >= 225)
                  {
                      rect.y = 220;
                  }
            rect.w += 10;
             rect.h += 10;
             shrunk = 0;
             normal = 1;
              changesong[0] = 1;
              }
}

   if(collision(&rect,&supersize))
   {
       rect.y--;

       if(normal)
       {
           if(rect.y >= 220)
                  {
                      rect.y = 215;
                  }
           rect.w += 10;
           rect.h += 10;
           normal = 0;
           huge = 1;
            changesong[0] = 1;
       }
   }

 if(collision(&rect,&destructiblewall))
   {
       if((normal) || (shrunk))
       if(destroyed[0])
       rect.y--;

         else if(huge)
       {
             destroyed[0]= 0;
           destroyed[1] = 1;

       }

   }

        else if(rect.y + rect.h >= 480 )
        rect.y--;

 }




    if(b[3])
   {
        rect.x++;
  for(int i = 0; i < 6; i++)
          if(collision(&rect,&rectarray[i]))
          rect.x--;

         if(collision(&rect,&shrinkblock))
{

    rect.x--;
          if(normal)
          {

             rect.w -= 10;
             rect.h -= 10;
             shrunk = 1;
             normal = 0;

             changesong[0] = 1;
          }
}

        if(collision(&rect,&enlargeblock))
{

             if(shrunk)
              {
                  if(rect.y >= 225)
                  {
                      rect.y = 220;
                  }
                  rect.w += 10;
             rect.h += 10;
             shrunk = 0;
             normal = 1;
              changesong[0] = 1;
              }
}

   if(collision(&rect,&supersize))
   {
       rect.x--;
       if(normal)
       {
           if(rect.y >= 225)
                  {
                      rect.y = 220;
                  }
           rect.w += 10;
           rect.h += 10;
           normal = 0;
           huge = 1;
            changesong[0] = 1;
       }
   }

   if(collision(&rect,&destructiblewall))
   {
       if((normal) || (shrunk))
       {
        if(destroyed[0])
       rect.x--;
       }

       else if(huge)
       {
           destroyed[0] = 0;
           destroyed[1] = 1;
       }

   }

         else if(rect.x + rect.w >= 641 )
        rect.x--;
   }

   if(b[4])
   FPS += 10;

   if(b[5])
   if(FPS > 10)
   FPS -= 10;

   if(b[6])
   {
       rect.x = 10;
       rect.y = 10;
       rect.w = 20;
       rect.h = 20;

       normal = 1;
       shrunk = 0;
       huge = 0;
        changesong[0] = 1;


   }


   if(destroyed[0])
   SDL_FillRect(screen,&destructiblewall, color5);

   else if(destroyed[1])
      SDL_FillRect(screen,&destructiblewall, color7);


SDL_FillRect(screen,&supersize, color6);
          SDL_FillRect(screen,&shrinkblock,color4);


    SDL_FillRect(screen,&rect,color3);



    SDL_Flip(screen);
    if(1000/FPS>SDL_GetTicks()-start)
    SDL_Delay(1000/FPS-(SDL_GetTicks()-start));
  }

  Mix_FreeMusic(music);
  Mix_CloseAudio();

  SDL_Quit();

  return 0;
}

Thanks again

[jefw123]

Please, I need help :D

[Stewbond]

I don't think you are going to find anyone willing to read 700 lines of code. Try reducing your code to about 20 lines explaining just how you make the current level and we can go from there.

[jefw123]

Ok thanks for that Strewbong, will end the post and repost later on when I have enough time to display the general structure of the program.

:D

[keineahnung]

Hmmm, a 700-line main function and you're finding it difficult to add new features... ;)
I think Bjarne himself would be in the same situation.
The first thing to do is to get this sorted out into smaller functions or preferably some classes, then you might find that the solution presents itself.
Good luck!