need help fixing up this code in allegro

[Bobish]

I'm working on a game and as you can see my codes a mess, ive been trying to break it up into smaller functions but I cant find any good places to break it up. I have one function writen but it doesn't work. As you can see my program also has some problems and any advice on how to fix it would be appriciated. I'm using Msvc++ 6 and allegro 4.00.

//#define DEBUGMODE //include this if your debugging

#include <stdio.h>
#include <allegro.h>
#include "test.h"

#define left		 1
#define right		 2
#define up			 3
#define down		 4
#define UpandLeft	 5
#define DownandLeft  6
#define UpandRight   7		
#define DownandRight 8
#define space		 9
#define ericw		 43  // width of eric.bmp
#define erich		 61  // hight of eric.bmp	 

struct bullet{ 
int bulletx; 
int bullety; 
int direction; 
}bullets[256]; // this stores information on all the bullets in the air

void calculate_shot_movment(int direction, int shot_draw_number);

PALETTE  Pal;
BITMAP *ImageBuffer;  
BITMAP *Ammobuffer;  // stores the the immage of the amunition

int main(void)
{
    BITMAP *dblbuffer;
	
	int x=100;
	int y=100;
	int keyvar=0;  //a keyboard buffer
	signed short shot_number=-1;   //which shot are we dealing with now
	int lastkeypressed=0; 
	signed short shot_draw_number=0;//which shot to draw
	int waskeydown=FALSE;  //used to tell if a keypressed was aready there

	allegro_init();
    
	install_keyboard();
    install_timer();        /* needed for `rest' function */

	set_color_depth(16); 
		if (set_gfx_mode(GFX_SAFE, 800, 600, 0, 0) < 0) 
		{
		printf("%s\n", allegro_error);
		exit(1);
		}

    clear(screen);
	
    // Pay attention!!! We HAVE to allocate memory for our memory bitmap
    dblbuffer = create_bitmap(SCREEN_W, SCREEN_H);
	clear(dblbuffer);
	
	ImageBuffer = load_bmp("Eric.bmp", Pal);
	Ammobuffer = load_bmp("rock.bmp", Pal);


		while(1)// main loop
		{
			/////////////////// input
			if (key[KEY_LEFT])
			{
			x--;
			lastkeypressed=left;
			}

			if (key[KEY_RIGHT])
			{
			x++;
			lastkeypressed=right;
			}
			
			if (key[KEY_UP])
			{
			y--;
			lastkeypressed=up;
			}

			if (key[KEY_DOWN])
			{
			y++;
			lastkeypressed=down;
			}
			
			if (key[KEY_LEFT] && key[KEY_UP])
			{
			lastkeypressed=UpandLeft;
			}
			
			if (key[KEY_LEFT] && key[KEY_DOWN])
			{
			lastkeypressed=DownandLeft;
			}

			if (key[KEY_RIGHT] && key[KEY_UP])
			{
			lastkeypressed=UpandRight;
			}

			if (key[KEY_RIGHT] && key[KEY_DOWN])
			{
			lastkeypressed=DownandRight;
			}
			/*
			if(keypressed())
				keyvar=readkey();
			else keyvar=0;
			*/	

			if (key[KEY_SPACE]  && waskeydown==FALSE)
			{	
				waskeydown=FALSE;// to prevent mutiple shots from one press

				shot_number++;
				if (shot_number>255)
				{shot_number = shot_number-255;}   // makes it so shot number has a max value of 255

				bullets[shot_number].direction=lastkeypressed;
				
				if(lastkeypressed==up || lastkeypressed==UpandLeft  || // if there was an up direction
					lastkeypressed==UpandRight)
				{
				bullets[shot_number].bullety=y-5;  // the y position of the bullet is five pixles above the player
				}
				
				else if(lastkeypressed==down || lastkeypressed==DownandLeft   // if there was a down direction
					||lastkeypressed==DownandRight)
				{
				bullets[shot_number].bullety=y+erich+5; // the y position of the bullet is five pixles below the player
				}

				else
				{
				bullets[shot_number].bullety=y+(erich/2); // the y position of the bullet is level with the player}
				}
				
				
				if(lastkeypressed==left || lastkeypressed==UpandLeft // if there was a left direction
					|| lastkeypressed==DownandLeft)
				{
				bullets[shot_number].bulletx=x-5;  //// the x position of the bullet is five pixles to the left of
				}
				
				else if(lastkeypressed==right || bullets[shot_number].direction==UpandRight // if there was a left direction
					|| lastkeypressed==DownandRight)
				{
				bullets[shot_number].bulletx=x+ericw+5;  //// the x position of the bullet is five pixles to the right of the player
				}
				
				else
				{
				bullets[shot_number].bulletx=x+(ericw/2);
				}
				
			}

			if (keypressed()!=TRUE)
			{
			waskeydown=FALSE;
			}


			//////////////////output		
		 

		if (lastkeypressed==right)
		{
			rectfill(dblbuffer, x - 1 , y      ,x + ericw - 1, y + erich, makecol(000,000,000));	/* erase from last place */
		}
		
		if (lastkeypressed==left)
		{
			rectfill(dblbuffer, x + 1 , y	   ,x + ericw + 1, y + erich, makecol(000,000,000));	/* erase from last place */
		}

		if (lastkeypressed==up)
		{
			rectfill(dblbuffer, x		, y + 1,x + ericw , y + erich + 1, makecol(000,000,000));	/* erase from last place */
		}
	
		if (lastkeypressed==down)
		{
			rectfill(dblbuffer, x		, y - 1,x + ericw ,y + erich - 1, makecol(000,000,000));	/* erase from last place */
		}
		
		if (lastkeypressed==UpandLeft)
		{
			rectfill(dblbuffer, x + 1 ,y + 1,x + ericw + 1, y + erich + 1, makecol(000,000,000));	/* erase from last place */
		}
		
		if (lastkeypressed==DownandLeft)
		{
			rectfill(dblbuffer, x + 1 ,y - 1,x + ericw + 1, y + erich - 1, makecol(000,000,000));	/* erase from last place */
		}

		if (lastkeypressed==UpandRight)
		{
			rectfill(dblbuffer, x - 1 ,y + 1,x + ericw - 1, y + erich + 1, makecol(000,000,000));	/* erase from last place */
		}
		
		if (lastkeypressed==DownandRight)
		{
			rectfill(dblbuffer, x - 1 ,y - 1,x + ericw - 1, y + erich - 1, makecol(000,000,000));	/* erase from last place */
		}
		
	//	if (lastkeypressed=space)
	//	{
	//		draw_sprite(dblbuffer, Ammobuffer, shotx, shoty);
	//		}
		
		draw_sprite(dblbuffer, ImageBuffer, x, y);  //draw bitmap on dblbuffer
		
		while (shot_draw_number < shot_number)
		{
		
			if (bullets[shot_draw_number].direction==DownandRight)
			{
			bullets[shot_draw_number].bulletx++;
			bullets[shot_draw_number].bullety++;
			}

			if (bullets[shot_draw_number].direction==UpandLeft)
			{
			bullets[shot_draw_number].bulletx--;
			bullets[shot_draw_number].bullety--;
			}

			if (bullets[shot_draw_number].direction==DownandLeft)
			{
			bullets[shot_draw_number].bulletx--;
			bullets[shot_draw_number].bullety++;
			}

			if (bullets[shot_draw_number].direction==UpandRight)
			{
			bullets[shot_draw_number].bulletx++;
			bullets[shot_draw_number].bullety--;
			}
			
			if (bullets[shot_draw_number].direction==down)
			{
			bullets[shot_draw_number].bullety++;
			}
			
			if (bullets[shot_draw_number].direction==up)
			{
			bullets[shot_draw_number].bullety--;
			}

			if (bullets[shot_draw_number].direction==left)
			{
			bullets[shot_draw_number].bulletx--;
			}

			if (bullets[shot_draw_number].direction==right)
			{
			bullets[shot_draw_number].bulletx++;
			}
		//calculate_shot_movment(bullets[shot_draw_number].direction, shot_draw_number);

		draw_sprite(dblbuffer, Ammobuffer, bullets[shot_number].bulletx, bullets[shot_draw_number].bullety);  //draw the bullet
		shot_draw_number++;
		}
		shot_draw_number=0;

		vsync();
		blit(dblbuffer, screen, 0, 0, 0, 0, SCREEN_W, SCREEN_H); // copy from double buffer to screen
		

			if (key[KEY_ESC])//clean up and quit
			{
			// Now, remember to FREE the memory you previously allocated
			destroy_bitmap(dblbuffer);
			destroy_bitmap(ImageBuffer);
			destroy_bitmap(Ammobuffer);
			allegro_exit();
			exit(1);
			}
		}
    return 0;
}
END_OF_MAIN();


// a function i'm working on to calculate a shot movement
void calculate_shot_movment(int direction, int shot_draw_number)
{
int* rbulletx = &bullets[shot_draw_number].bulletx;  // note to self change to references
int* rbullety = &bullets[shot_draw_number].bullety;

			if (direction==DownandRight)
			{
			*rbulletx++;
			*rbullety++;
			}

			if (direction==UpandLeft)
			{
			*rbulletx--;
			*rbullety--;
			}

			if (direction==DownandLeft)
			{
			*rbulletx--;
			*rbullety++;
			}

			if (direction==UpandRight)
			{
			*rbulletx++;
			*rbullety--;
			}
			
			if (direction==down)
			{
			*rbullety++;
			}
			
			if (direction==up)
			{
			*rbullety--;
			}

			if (direction==left)
			{
			*rbulletx--;
			}

			if (direction==right)
			{
			*rbulletx++;
			}

}

[Magos]

Thats a lot of code... You could try to break it up to get something like this:

bool Setup()
{
  if(AllegroInit()==false) return false;
  if(InstallKeyboard()==false) return false;
  if(InstallTimer()==false) return false;
  if(InstallWhatever()==false) return false;
  return true;
}

int main()
{
  if(Setup()==true)
  {
    while(GameIsOn==true)
    {
      KeyboardCheck();
      CalculateStuff();
      RenderScreen();
    }
    ShutDown();
  }
}

[bobish]

okay i am running this function: in the place of those three install/init functions but when i do keyboard imput down't work, including set_color_depth didn't work ether. Am i going to have to use pointers to those functions?

int gameinit()
{
if(allegro_init()==FALSE) return FALSE;
if(install_keyboard()==FALSE) return FALSE;
if(install_timer()==FALSE) return FALSE;
return TRUE;
}

[compjinx]

I just write all my general stuff in classes and put them into external cpp files.

did you include allegro.h into all the cpp/h files you have in your project?

[Bobish]

you can just look at my code to see that I included allegro.h and I personaly try to avoid using classes.

[jdinger]

Originally posted by Bobish
you can just look at my code to see that I included allegro.h and I personaly try to avoid using classes.

Your code snippet shows code from only one file. The question is did you include "allegro.h" in all your cpp/h files.

Why would you avoid classes? I know some people go over-board with "wrapper-itus" but if you use them properly classes make manipulating your objects SO much easier.

[pode]

man you've got to help me with a spaceshooter game

i've done some code but one of my problems are how to make
a shot that moves actually i have mannaged to do that also but
i cant "shoot" many shots i a row

please help.

[Bobish]

well you could do what I did of having an array of structs called bullets, the size of the array determines the max number of bullets.

[Bobish]

so any more advice on how to clean up my code?

[compjinx]

Can't you change to a system to 360 directions instead of just 8?
then you can do some hard calculation instead of a whole bunch of IF statments.
like:

fx=fx-cos(angle)/20;
fy=fy-sin(angle)/20;
x+=fx;
y+=fy;

where FX and FY are the forces acting on X and Y, ANGLE is the angle the bullet is pointing,ect
At least I think thats what this code does, I didn't get much sleep last night so I am a little tired.

[compjinx]

WHAT!!!! why am I labeled as a Senior Member? I havn't posted THAT much! im not even a good programmer!

[bobish]

I think ill stick to if statements for now untill i clean this code up a bit, for one thing those math.h functions can be bit slow though it would be nice to change this at some point so then i would have an engine ready to be any type of game.
Okay i have an init function working but i still can't get any functions using references or pointers to global variables and ones from main. How can i make function change variables outside of the function?