Struct question

[jac77794]

Hi again. I was playing around and can't understand why my code won't compile when I use a struct the way it is used in other c++ tutorials or anyway I use it.

I know this code complies

Code: Select all

#include <SPI.h>
#include <Gamebuino.h>

Gamebuino gb = Gamebuino();


int playerx = LCDWIDTH/2 ;
int playery = (LCDHEIGHT/6)*5 ;


const byte plane[] PROGMEM = {
  8,8,
  B11111111,
  B11111111,
  B11111111,
  B11111111,
  B11111111,
  B11111111,
  B11111111,
};


void setup (){ // Setup of the game
  gb.begin();
  gb.titleScreen(F("TBA"));
}


void loop(){
  if(gb.update()){
     if(gb.buttons.repeat(BTN_RIGHT,1)){ //Make player move right
      if(playerx != LCDWIDTH){ //in bound check
      playerx = playerx + 1;
      }
    }
    if(gb.buttons.repeat(BTN_LEFT,1)){ //Make player move left
      if(playerx != 0){ /// in bound check
        playerx = playerx -1;
       }
    }
  }
} 

But not this

Code: Select all

#include <SPI.h>
#include <Gamebuino.h>

Gamebuino gb = Gamebuino();

struct info {
  int x;
  int y;
} player;

player.x = LCDWIDTH;
player.y = LCDHEIGHT;


const byte plane[] PROGMEM = {
  8,8,
  B11111111,
  B11111111,
  B11111111,
  B11111111,
  B11111111,
  B11111111,
  B11111111,
};


void setup (){ // Setup of the game
  gb.begin();
  gb.titleScreen(F("TBA"));
}


void loop(){
  if(gb.update()){
     if(gb.buttons.repeat(BTN_RIGHT,1)){ //Make player move right
      if(player.x != LCDWIDTH){ //in bound check
      player.x = player.x + 1;
      }
    }
    if(gb.buttons.repeat(BTN_LEFT,1)){ //Make player move left
      if(player.x != 0){ /// in bound check
        player.x = player.x -1;
       }
    }
  }
} 

sketch_aug02b:11: error: expected constructor, destructor, or type conversion before '.' token
sketch_aug02b:12: error: expected constructor, destructor, or type conversion before '.' token
sketch_aug02b.ino:15: warning: only initialized variables can be placed into program memory area
sketch_aug02b.ino: In function 'void setup()':
sketch_aug02b.ino:29: warning: only initialized variables can be placed into program memory area



Above is the error message I get. Why doesn't it work. Does the Gamebuino work differently? All help would be much appreciated.

[Limited]

Your struct and declaration of player is wrong. Try this.

Code: Select all

 
typedef struct {
  int x;
  int y;
} Player;
 
Player player;

player.x = LCDWIDTH;
player.y = LCDHEIGHT;


[jac77794]

Thanks for the advice. I tried it and it still won't compile.

Code: Select all

#include <SPI.h>
#include <Gamebuino.h>

Gamebuino gb = Gamebuino();

 
typedef struct {
  int x;
  int y;
} Player;
 
Player player;

player.x = LCDWIDTH;
player.y = LCDHEIGHT;


const byte plane[] PROGMEM = {
  8,8,
  B11111111,
  B11111111,
  B11111111,
  B11111111,
  B11111111,
  B11111111,
  B11111111,
};


void setup (){ // Setup of the game
  gb.begin();
  gb.titleScreen(F("TBA"));
}


void loop(){
  if(gb.update()){
     if(gb.buttons.repeat(BTN_RIGHT,1)){ //Make player move right
      if(player.x != LCDWIDTH){ //in bound check
      player.x = player.x + 1;
      }
    }
    if(gb.buttons.repeat(BTN_LEFT,1)){ //Make player move left
      if(player.x != 0){ /// in bound check
        player.x = player.x -1;
       }
    }
  }
} 

These are the error messages that I am getting.

sketch_aug02b:14: error: expected constructor, destructor, or type conversion before '.' token
sketch_aug02b:15: error: expected constructor, destructor, or type conversion before '.' token
sketch_aug02b.ino:18: warning: only initialized variables can be placed into program memory area
sketch_aug02b.ino: In function 'void setup()':
sketch_aug02b.ino:32: warning: only initialized variables can be placed into program memory area

[rodot]

That's because you can't run instruction out of any function, you have to place them either in setup() or loop() (or another function).

So if you put the following in setup() instead of global scope it compiles fine

Code: Select all

  player.x = LCDWIDTH;
  player.y = LCDHEIGHT;

Here is the corrected code:

Code: Select all

#include <SPI.h>
#include <Gamebuino.h>

Gamebuino gb = Gamebuino();

 
typedef struct {
  int x;
  int y;
} Player;
 
Player player;


const byte plane[] PROGMEM = {
  8,8,
  B11111111,
  B11111111,
  B11111111,
  B11111111,
  B11111111,
  B11111111,
  B11111111,
};


void setup (){ // Setup of the game
  gb.begin();
  gb.titleScreen(F("TBA"));
  player.x = LCDWIDTH;
  player.y = LCDHEIGHT;
}


void loop(){
  if(gb.update()){
     if(gb.buttons.repeat(BTN_RIGHT,1)){ //Make player move right
      if(player.x != LCDWIDTH){ //in bound check
      player.x = player.x + 1;
      }
    }
    if(gb.buttons.repeat(BTN_LEFT,1)){ //Make player move left
      if(player.x != 0){ /// in bound check
        player.x = player.x -1;
       }
    }
  }
}

[jac77794]

Thanks rodot it works great now.

Also I am loving my Gamebuino thanks for starting this project it is giving an accessible and engaging platform to learn to code.