Thread: calling member function from constructor

I have this code for a class called Character, If I initialize a character object my program breaks ( by calling constructor) ... but If i comment out the member function cut_sheet() then my program works as intended.

any idea?

Code:

Character::Character()
{
	sheet_file = "sprites.png";
	cut_sheet();
	dir = DOWN;
	frame = 0;
	velocity_x = 0;
	velocity_y = 0;
}

void Character::cut_sheet()
{
	for(int i=0;i<sizeof(ani_up)/sizeof(SDL_Rect*);++i)
	{
		ani_up[i].x = 55 + i*40;
		ani_up[i].y = 320;
		ani_up[i].w = 20;
		ani_up[i].h = 30;
	}
	for(int i=0;i<sizeof(ani_down)/sizeof(SDL_Rect*);++i)
	{
		ani_down[i].x = 55 + i*40;
		ani_down[i].y = 360;
		ani_down[i].w = 20;
		ani_down[i].h = 30;
	}
	for(int i=0;i<sizeof(ani_left)/sizeof(SDL_Rect*);++i)
	{
		ani_left[i].x = 55 + i*40;
		ani_left[i].y = 400;
		ani_left[i].w = 20;
		ani_left[i].h = 30;
	}
	for(int i=0;i<sizeof(ani_right)/sizeof(SDL_Rect*);++i)
	{
		ani_right[i].x = 55 + i*40;
		ani_right[i].y = 440;
		ani_right[i].w = 20;
		ani_right[i].h = 30;
	}
}

And I am initializing it something like this in another file

Code:

Character *unit = new Character();

Calling a member function from a constructor is OK (assuming it doesn't try to use the members whose values you have not set yet).

It is more likely that your cut_sheet is broken (e.g goes out of bounds). For example, perhaps you should be dividing by sizeof(*ani_up) etc (assuming it is a fixed-sized array).

Code:

for(int i=0;i<sizeof(ani_up)/sizeof(SDL_Rect);++i)
//or
for(int i = 0; i < sizeof(ani_up) / sizeof(*ani_up); ++i)
//or even
for (int i = 0; i < boost::size(ani_up); ++i) //safest of them all, you can also implement your own

The size of the pointer to SDL_Rect is irrelevant to the calculation, because you have an array of SDL_Rects, not pointers.