passing a string to textprinf

passing a string to textprinf_ex

notwist

Member #8,248

January 2007

I want to store a description inside of a map tile structure array and display it on the screen.

so i create this structure type:

struct tile
{
const char *desc;
bool walkable;
char img;
int colorR,colorG,colorB;
unsigned int sapling, tree, rock;
} floor, rock, rocksoil, grass, wall;

define it with:

floor.desc="Stone floor.";
floor.walkable=1;
floor.img=46;
floor.colorR = 100;
floor.colorG = 200;
floor.colorB = 100;

move a little '@' left and right along a single horizontal line

if (key[KEY_4_PAD]&& player.x>0){
player.x-=8;
clear_bitmap(screen);
}

if (key[KEY_6_PAD]&& player.x<472){
player.x+=8;
clear_bitmap(screen);
}

and everything falls apart when i add the line

textprintf_ex(screen, font, 0, 8, makecol(map[player.x].colorR, map[player.x].colorG, map[player.x].colorB), -1, "%s", map[player.x].desc);

DanielH

Member #934

January 2001

Is player.x within the parameters of map?
Meaning if map is defined as map[ n ] then player.x should be from 0 to n-1

Is desc defined of map[ player.x ].desc?

what is desc? what type of variable is it. You said string. Is it a C string or a C++ string?

std::string desc or
char desc[] or
char *desc or
...

Without seeing more code, that's all I say about that.

YouTube Coding Channel

notwist

Member #8,248

January 2007

struct Player
{
char img;
int colorR, colorG, colorB;
int x;
} player;

player.img=64;
player.colorR=140;
player.colorG=140;
player.colorB=140;
player.x=0;

tile map[80];
for(x=0;x<79;x++)
{

i=rand()%8+1;
if(i==1)
map[x]=grass;
else

map[x]=rocksoil;

}

DanielH

Member #934

January 2001

Now I see that map is of tile

and tile is of
char *desc

Is player.x defined before you use it?

And when is each tile in map defined?

YouTube Coding Channel

notwist

Member #8,248

January 2007

player x is defined and set to 0 before it is referenced

this is the main screen drawing loop

for(x=0;x<80;x++)
{
/* multiply by 8 to allow for 8 pixels per character */
xa=x*8;
if (xa == player.x)
{
textprintf_ex(screen, font, xa, 0, makecol(0, 0, 0),-1, "%c", 32);
}
else {

textprintf_ex(screen, font, xa, 0, makecol(map[x].colorR, map[x].colorG, map[x].colorB),-1, "%c", map[x].img);
}

textprintf_ex(screen, font, 0, 8, makecol(map[player.x].colorR, map[player.x].colorG, map[player.x].colorB), -1, "%s", map[player.x].desc);
textprintf_ex(screen, font, 0, 16, makecol(player.colorR, player.colorG, player.colorB), -1, "%d ", player.x/8 );

textprintf_ex(screen, font, player.x, 0, makecol(player.colorR, player.colorG,player.colorB),-1, "%c", player.img);
}

LennyLen

Member #5,313

December 2004

Quote:

and everything falls apart when i add the line

Care to explain what you mean by 'falls apart'?

DanielH

Member #934

January 2001

Do this and tell me what happens

if ( map[player.x].desc )
}
    textprintf_ex(screen, font, 0, 8, makecol(map[player.x].colorR, map[player.x].colorG, map[player.x].colorB), -1, "%s", map[player.x].desc);
{
else
{
    textout_ex(screen, font, "null", 0, 8, makecol(map[player.x].colorR, map[player.x].colorG, map[player.x].colorB), -1 );
}

And I should have said it earlier, but use 'code' brackets when displaying code on this website.

[code]
[/code]

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notwist

Member #8,248

January 2007

sure, it compiles, and runs

i can iterate the character and it will display the string, however the string doesnt coorelate to the tile the character is standing on

the pointer appears to iterate beyond the array, as it will display strings of desc then it starts to display random symbols then the app freezes

//same thing happens when i replace my map[].desc with the given conditional display

1#include <cstdlib>
2#include <iostream>
3#include <allegro.h>
4#include <string>
5#include <time.h>
6using namespace std;
7 
8 
9 
10int main()
11{
  int x, y, xa, ya, i,j ,ii, jj;
  srand(time(NULL));
  BITMAP *buffer;
15 
  allegro_init();
  install_keyboard();
  set_gfx_mode( GFX_AUTODETECT, 640, 480, 0, 0);    
19/* tile data type and declarations*/    
  struct tile
     {
      const char *desc;
      bool walkable;
      char img;
      int colorR,colorG,colorB;
      unsigned int sapling, tree, rock;
      } floor, rock, rocksoil, grass, wall;
      
      
30/*player position etc.*/
  struct Player
         {
         char img;
         int colorR, colorG, colorB;
         int x;                
         } player;
         
         player.img=64;
         player.colorR=140;
         player.colorG=140;
         player.colorB=140;
         player.x=0;
         
/* tile definitions */    
  floor.desc="Stone floor.";
  floor.walkable=1;
  floor.img=46;
  floor.colorR = 100;
  floor.colorG = 200;
  floor.colorB = 100;
      
  rock.walkable=0;
  rock.img=46;
  rock.colorR = 110;
  rock.colorG = 110;
  rock.colorB = 110;
  rock.desc="Bare rock.";
  
  rocksoil.walkable=0;
  rocksoil.img=35;
  rocksoil.colorR = 120;
  rocksoil.colorG = 44;
  rocksoil.colorB = 1;
  rocksoil.desc="Rocky soil.";
  
  grass.walkable=0;
  grass.img=118;
  grass.colorR = 77;
  grass.colorG = 179;
  grass.colorB = 41;
  grass.desc="Grassy soil.";
  
  tile map[80];
for(x=0;x<79;x++)
                {
                
               
                i=rand()%8+1;
                if(i==1)
                         map[x]=grass;
                        else
                         
                          map[x]=rocksoil;
                          
                         
                }
87 
/*
89x=rand()%70;
90
          ii=(rand()%9+3)+x;
          
          for(i=x;i<ii;i++){
                            
                            map<i>=rock;
                            
                            }
  
  /* Do this over and over again as long as the player hasn't pressed the
     excape key */
  while ( !key[KEY_ESC] )
  {
  
      
      clear_keybuf();
      acquire_screen();
      
      
 /* movement commands allowing left and right movement*/     
110 
      if (key[KEY_4_PAD]&& player.x>0){
         player.x-=8;
         clear_bitmap(screen);
         }
115 
         
      if (key[KEY_6_PAD]&& player.x<472){
         player.x+=8;
         clear_bitmap(screen);
         }
121 
      /* draw the strip of 80 tiles at the top of the screen and the player skipping the tile where the player is located*/
      for(x=0;x<80;x++)
      {
                                /* multiply by 8 to allow for 8 pixels per character */
                                  xa=x*8;
                                         if (xa == player.x) 
                                         {
       textprintf_ex(screen, font, xa, 0, makecol(0, 0, 0),-1, "%c", 32);
                                         }
       else                  {
                                                         
       textprintf_ex(screen, font, xa, 0, makecol(map[x].colorR, map[x].colorG, map[x].colorB),-1, "%c", map[x].img);
                             }                 
                                 
       if ( map[player.x].desc )
137{
  textprintf_ex(screen, font, 0, 8, makecol(map[player.x].colorR, map[player.x].colorG, map[player.x].colorB), -1, "%s", map[player.x].desc);
139}
140else
141{
  textout_ex(screen, font, "null", 0, 8, makecol(map[player.x].colorR, map[player.x].colorG, map[player.x].colorB), -1 );
143}
144 
       textprintf_ex(screen, font, 0, 16, makecol(player.colorR, player.colorG, player.colorB), -1, "%d ", player.x/8 );
       
       
       textprintf_ex(screen, font, player.x, 0, makecol(player.colorR, player.colorG,player.colorB),-1, "%c", player.img);
       }
      
      
      release_screen();
      
      rest(50);
155 
}    
  return 0;
  
159} 
160END_OF_MAIN()

DanielH

Member #934

January 2001

EDIT

I know that you can put structure declarations inside the function, but !!!NO!!!

map[ x ] = grass;

What is that?

How about

map[ x ].walkable = grass.walkable;
map[ x ].img = grass.img;
map[ x ].colorR = grass.colorR;
map[ x ].colorG = grass.colorG;
map[ x ].colorB = grass.colorB;
map[ x ].desc = grass.desc;

Or you could do

tile *map[ 80 ];

map[ x ] = &grass;

YouTube Coding Channel

notwist

Member #8,248

January 2007

if grass is and map[x] are the same data type can't you just assign the values of grass to the array node x?

gnolam

Member #2,030

March 2002

1) Edit your posts to use code tags. They're nigh unreadable without indentation.

Quote:

floor.desc="Stone floor.";

There's your problem.

--
Move to the Democratic People's Republic of Vivendi Universal (formerly known as Sweden) - officially democracy- and privacy-free since 2008-06-18!

LennyLen

Member #5,313

December 2004

And in case you don't know what gnolam means, that line should be:

strcpy(floor.desc, "Stone floor");