Enter charaters/numbers from Keypad

no-reply@allegro.cc (Kokxxx12) — Sat, 14 Mar 2020 04:12:57 +0000

Hi, I create kind od board game in Allegro and I want input numbers and dispplay these numbers on the screen. I try using sscanf and sprintf but still numbers dont display on the screen.

int width = 0;
int length = 40;
char buff[256];
char buff1[256];
char a;

if(key[KEY_RIGHT])
{
if(width<=340)
{
clear_to_color(buffer,makecol(255,255,0));
width+=40;
blit(pole1,buffer,0,0,width,length,40,40);
clear_to_color(pole1,makecol(128,0,0));
sscanf(buff,"%d",&a);

textout_ex(buffer,font,buff,width+20,length+20, makecol(255, 0, 128),-1);

rest(100);

no-reply@allegro.cc (MikiZX) — Sat, 14 Mar 2020 07:45:34 +0000

Personally I do not see how you enter the numbers in the 'buff'.

Possibly 'fgets' or 'getline' are missing in your source code.

If I was programming this without the standard C functions I would do it like this:

#SelectExpand
  1// initialization
  2// initialization
  3// initialization
  4
  5   ALLEGRO_KEYBOARD_STATE kbdstate;
  6   char buff[256];
  7   int buff_pos;
  8   int a;        // better use INT though CHAR might work as well - i am not sure
  9
 10   if (!al_install_keyboard()) 
 11      {
 12      abort_example("Error installing keyboard.\n");
 13      return 1;
 14      }
 15   buff_pos=0;
 16
 17
 18
 19// in your program's main loop 
 20// (this would execute many times to receive multiple numbers)
 21// in your program's main loop
 22// in your program's main loop
 23
 24       al_get_keyboard_state(&kbdstate);
 25
 26       if (al_key_down(&kbdstate, ALLEGRO_KEY_PAD_0)) 
 27       {
 28    buff[buff_pos]=0;
 29          buff_pos++;   
 30       }
 31
 32       if (al_key_down(&kbdstate, ALLEGRO_KEY_PAD_1)) 
 33       {
 34    buff[buff_pos]=1;
 35          buff_pos++;   
 36       }
 37
 38       if (al_key_down(&kbdstate, ALLEGRO_KEY_PAD_2)) 
 39       {
 40    buff[buff_pos]=2;
 41          buff_pos++;   
 42       }
 43
 44  ....
 45
 46       if (al_key_down(&kbdstate, ALLEGRO_KEY_PAD_9)) 
 47       {
 48    buff[buff_pos]=9;
 49          buff_pos++;   
 50       }
 51
 52  if (buff_pos>255) buff_pos=0;
 53
 54  printf("%s \n", buff);    // print on screen
 55
 56  sscanf(buff,"%d",&a);    // convert text buffer to integer 'a'

no-reply@allegro.cc (Kokxxx12) — Sat, 14 Mar 2020 17:00:52 +0000

I don't understand this code at all. Can you describe please what are you doing in this code?

no-reply@allegro.cc (DuncanShine) — Sat, 14 Mar 2020 17:49:33 +0000

I just avoided all the buffer stuff and converted to const char* using .c_str() then outputted that using al_draw_text.

no-reply@allegro.cc (Kokxxx12) — Sat, 14 Mar 2020 17:55:52 +0000

What doing this program? I creating sudoku game and I want to input numbers into the grid from keypad

no-reply@allegro.cc (Edgar Reynaldo) — Sat, 14 Mar 2020 20:00:57 +0000

Turn Numlock on and monitor ALLEGRO_EVENT_KEY_CHAR events.

no-reply@allegro.cc (MikiZX) — Sat, 14 Mar 2020 20:05:19 +0000

Yeah, possibly your num pad lock is off.

if you wish a complete example program this should help (once you run this program you should see two windows - one with text showing the key you pressed and one with graphics that shows different color depending on the key pressed):

#SelectExpand
   1#include 
   2#include 
   3
   4const float FPS = 60;
   5
   6ALLEGRO_DISPLAY *display = NULL;
   7ALLEGRO_EVENT_QUEUE *event_queue = NULL;
   8ALLEGRO_TIMER *timer1 = NULL;
   9
  10bool redraw = true;
  11int input_number = 0;
  12
  13// isolating cleanup code in a single function because we use this code many times
  14// doing this will keep the rest of the source code easier to read
  15void close_and_exit()
  16{
  17   if (timer1) al_destroy_timer(timer1);
  18   if (display) al_destroy_display(display);
  19   if (event_queue) al_destroy_event_queue(event_queue);
  20   al_uninstall_system();
  21}
  22
  23// the program execution starts here with 'main' function
  24int main(int argc, char **argv){
  25
  26   // here we initialize different parts of Allegro
  27   if(!al_init()) {
  28      fprintf(stderr, "failed to initialize allegro!\n");
  29      return -1;
  30   }
  31
  32   display = al_create_display(640, 480);
  33   if(!display) {
  34      fprintf(stderr, "failed to create display!\n");
  35      close_and_exit();
  36   }
  37
  38   if (!al_install_keyboard())
  39       {
  40       fprintf(stderr, "Error installing keyboard.\n");
  41       close_and_exit();
  42       }
  43
  44   event_queue = al_create_event_queue();
  45   if(!event_queue) {
  46      fprintf(stderr, "failed to create event_queue!\n");
  47      close_and_exit();
  48   }
  49
  50   timer1 = al_create_timer(1.0 / FPS);
  51   if(!timer1) {
  52      fprintf(stderr, "failed to create timer!\n");
  53      close_and_exit();
  54   }
  55
  56   al_register_event_source(event_queue, al_get_keyboard_event_source());
  57
  58   al_register_event_source(event_queue, al_get_display_event_source(display));
  59
  60   al_register_event_source(event_queue, al_get_timer_event_source(timer1));
  61
  62   al_start_timer(timer1);
  63
  64
  65   // this is the main loop that will receive keypresses, do game logic processing and draw our game on the screen
  66   while(1)
  67   {
  68      ALLEGRO_EVENT ev;
  69      al_wait_for_event(event_queue, &ev);
  70
  71      if(ev.type == ALLEGRO_EVENT_TIMER) {
  72         redraw = true;
  73      }
  74
  75      if(ev.type == ALLEGRO_EVENT_KEY_DOWN) {
  76         if (ev.keyboard.keycode>=ALLEGRO_KEY_PAD_1 && ev.keyboard.keycode<=ALLEGRO_KEY_PAD_9)
  77         // calculate input number from input keycode
  78         // since the ALLEGRO keycodes for numeric pad are sequential
  79         // (i.e. ALLEGRO_KEY_PAD_0 is value of 36, ALLEGRO_KEY_PAD_1 is value of 37,
  80         //  ALLEGRO_KEY_PAD_2 is value of 38, ... until ALLEGRO_KEY_PAD_9
  81         // we can take the input keycode and subtract value of ALLEGRO_KEY_PAD_0 to get the
  82         // inputed number ... i.e. ALLEGRO_KEY_PAD_1-ALLEGRO_KEY_PAD_0=1 because 37-26=1
  83            input_number=ev.keyboard.keycode-ALLEGRO_KEY_PAD_0;
  84            else
  85            input_number=0;
  86
  87         if (ev.keyboard.keycode==ALLEGRO_KEY_ESCAPE)
  88            close_and_exit();
  89      }
  90
  91      if(ev.type == ALLEGRO_EVENT_DISPLAY_CLOSE) {
  92         break;
  93      }
  94
  95      if(redraw && al_is_event_queue_empty(event_queue))
  96        {
  97         redraw = false;
  98         // convert inputed number to colors (0=black, 1=blue, 2=red, ...)
  99         int r,g,b;
 100         r=((input_number&2)/2) * 127;
 101         g=((input_number&4)/4) * 127;
 102         b=(input_number&1) * 127;
 103         al_clear_to_color(al_map_rgb(r,g,b));  // clear graphics screen
 104
 105         system("@cls||clear");     // clear the text console window
 106         printf("%d\n",input_number);   // print out the number entered
 107
 108         al_flip_display();
 109      }
 110   }
 111    close_and_exit();
 112}

no-reply@allegro.cc (Edgar Reynaldo) — Sat, 14 Mar 2020 20:27:26 +0000

MikiZX, note - you have a void function returning 0. I assume you meant to call the function and then return 0.

no-reply@allegro.cc (MikiZX) — Sun, 15 Mar 2020 00:12:39 +0000

Thanks Edgar, fixed now.

@Kokxxx12, I hope this can help in some way - if you still have difficulties understanding how it works then please let us know which part you do understand and we will explain the rest.

no-reply@allegro.cc (LennyLen) — Sun, 15 Mar 2020 04:21:43 +0000

It might be time to point out that the OP is using A4, not A5.

no-reply@allegro.cc (Edgar Reynaldo) — Sun, 15 Mar 2020 08:38:31 +0000

I need fucking glasses.

Kokxxx12, with Allegro 4 you can use readkey and shift the value 8 bits to get the keycode, then convert it to a number or digit.

no-reply@allegro.cc (MikiZX) — Sun, 15 Mar 2020 10:39:47 +0000

oops.. glasses for me too then. Sorry Kokxxx12, now I understand why the code was not understandable.
I don't think I will be able to help with A4 though.
@LennyLen, thank you for pointing this out.