struct pointers

seidel · 08-10-2009, 12:41 PM

Hi!

I was wondering how it would be done to point to struct, like this

you have two dif structs

Code:

typedef struct {
     float face1,face2,face3;
    char name[200];
     int num_objs;

} object_list;

typedef struct {
     scene_name
       
}scenes;


object_list obj[50];
scenes scene[50];

where scene would be 1 element, and pointing to several objects with in the

(this is pseudo and what i want todo)

scene[0].obj[0].numobj;

result with how many objects there are in scene 0, right now i add the start object and the end object into the scene struct so, when drawing the 3d object, i do
this more or less.

Code:

for (counter=startobj;counter<endobj;counter++)

anyone could elaborate how i could do this?

Any help are appricated!

- seidel

**sean** · 08-10-2009, 12:52 PM

If you're asking how to iterate through a series of structs, you have at least two options. Here they are in somewhat-pseudo-code:

As an array

Code:

my_type objects[50];
int length = 50;
...
for(i = 0; i < length; i++) {
     // Do some stuff with objects[i]
}

As a linked list (i.e. the struct contains a pointer that is used to point to the next instance in the series)

Code:

struct my_type {
    int data[50];
    struct my_type * next;
} current;
...
for(current = start; current.next != NULL; current = current.net) {
    // Do some stuff with current
}

kcpilot · 08-11-2009, 10:19 AM

For one thing, struct scene DOES NOT contain an 'obj', so your 'scene[0].obj[0].numobj;' is completely bogus.

To do what you want to do, you would have to include the structure 'object_list' INSIDE your scene struct.

Code:

typedef struct {
     float face1,face2,face3;
    char name[200];
     int num_objs;

} object_list;

typedef struct {
     scene_name
     struct object_list[50];
       
}scenes;

08-10-2009, 12:41 PM	#1
seidel Registered User Join Date: Feb 2008 Posts: 5	struct pointers Hi! I was wondering how it would be done to point to struct, like this you have two dif structs Code: typedef struct { float face1,face2,face3; char name[200]; int num_objs; } object_list; typedef struct { scene_name }scenes; object_list obj[50]; scenes scene[50]; where scene would be 1 element, and pointing to several objects with in the (this is pseudo and what i want todo) scene[0].obj[0].numobj; result with how many objects there are in scene 0, right now i add the start object and the end object into the scene struct so, when drawing the 3d object, i do this more or less. Code: for (counter=startobj;counter<endobj;counter++) anyone could elaborate how i could do this? Any help are appricated! - seidel
seidel is offline

08-10-2009, 12:52 PM	#2
sean Super Moderator Join Date: Sep 2001 Posts: 4,680	If you're asking how to iterate through a series of structs, you have at least two options. Here they are in somewhat-pseudo-code: As an array Code: my_type objects[50]; int length = 50; ... for(i = 0; i < length; i++) { // Do some stuff with objects[i] } As a linked list (i.e. the struct contains a pointer that is used to point to the next instance in the series) Code: struct my_type { int data[50]; struct my_type * next; } current; ... for(current = start; current.next != NULL; current = current.net) { // Do some stuff with current }
sean is offline

08-11-2009, 10:19 AM	#3
kcpilot Registered User Join Date: Jan 2007 Location: Euless, TX Posts: 135	For one thing, struct scene DOES NOT contain an 'obj', so your 'scene[0].obj[0].numobj;' is completely bogus. To do what you want to do, you would have to include the structure 'object_list' INSIDE your scene struct. Code: typedef struct { float face1,face2,face3; char name[200]; int num_objs; } object_list; typedef struct { scene_name struct object_list[50]; }scenes;
kcpilot is offline

Thread Tools
Show Printable Version Email this Page
Display Modes
Linear Mode Switch to Hybrid Mode Switch to Threaded Mode

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
Concatenating in linked list	drater	C Programming	12	05-02-2008 11:10 PM
Global Variables	Taka	C Programming	34	11-02-2007 03:25 AM
Function validation.	Fhl	C Programming	10	02-22-2006 08:18 AM
Array of struct pointers - Losing my mind	drucillica	C Programming	5	11-12-2005 11:50 PM
Pointers on pointers to pointers please...	Morgan	C Programming	2	05-16-2003 11:24 AM