Pointer&Array problem

**LloydUzari** · 08-15-2004

Im making a little graphics engine, but not much about that in this topic. My problem right now is with pointers and arrays(if you didnt notice)

I have a Dynamic 3D array, which 'seems' to work, havent gotten an error from it, but I was wondering, because its an array of structs, which is in an array of class's, how would I access it?

'class[0]->struct[0]->variable'? That was my first guess, but it seems to run errors...

Also, how would I declare an instance of my class, and would I need to declare my struct?

Thanks for any help, its my first time working with an array of structs/class's

**Salem** · 08-15-2004

Show how you declare and initialise these structures / arrays

**The Brain** · 08-15-2004

this topic looks kinda good.. i look forward to seeing some code

**elad** · 08-15-2004

My interpretation of a 3D array of structs which is in an array of classes

Code:

struct Enigma
{
	int color;
	int shade;
};
 
class holdingClass
{
   public:
	 Enigma enigmaArray[10][10][10];
};
 
holdingClass game[10];

if game and enigmaArray are declared with static memory as above then to access a given Enigma member in game you would do this:

game[x].enigmaArray[a][b][c].color;
game[x].enigmaArray[a][b][c].shade;

if enigma is declared using dynamic memory, but game uses static memory, then:

game[x].enigmaArray[a][b][c]->color;
game[x].enigmaArray[a][b][c]->shade;

if both enigma and game are declared using dynamic memory then:

game[x]->enigmaArray[a][b][c]->color;
game[x]->enigmaArray[a][b][c]->shade;

It gets a little more complicated if game or enigmaArray are declared with private access, but it's still doable.

**LloydUzari** · 08-15-2004

Ok heres some code:

Code:

//In class:
struct tile ***iso_map;

//Declaring 3D array of structs:
**iso_map=new int[map_height]; //dynamically declare 3D array
for (int a=0; a<map_height; a++) {
    *iso_map[a]=new int[map_width];
    for (int b; b<map_width; b++) {
        iso_map[a][b]=new int[map_length];
    }
}

//Above class:
class map *maps;

//Declaring map(only 1 right now):
maps=new class[1];

Thats what is there right now, split alot of course cause its like 250 lines of code

After looking at your stuff, there seems to be a better way to declare the array of class's, but the problem is that Im using a header file to declare the maps and such, and they arent at the top of the file(need to be below class and struct) Im starting to think that I should change it to file i/o now instead of later? I think that might fix. Ill go through my code, fix it up, and try posting more later.
Until then, you guys try to help

Edit: Heres the last error'd line, annoying one it is. Gives me a few things to ask, but first the code:

Code:

draw_sprite(buffer, (BITMAP *)tiles[maps[0].iso_map[z][x][y].tilename].dat, (maps[0].map_start[0])+(x*(maps[0].map_difference[0])), (maps[0].map_start[1])+(y*(maps[0].map_difference[1]));

(Long, eh?

)
1. Can you declare what tile in the method I used, or is there a problem in that?
2. Why does it act like 'tiles' is a function?
3. Where is the syntax error?(Im guessing the tiles thing)

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