define struct

[Michael Sgier]

Hello
what's going on here and some basic questions:
- define...unfortunately i haven't found it in my book so what exactly
does this?
- then SKYBOXVERTEX is declared...i understand the first struct but i
can only
guess what's going on from here on: SKYBOXVERTEX pBoxList[ 8 ] =
- I get the error: `WORD' undeclared (first use this function) Why? and
how shall I do it correctly?
THANKS and regards
Michael
#define BOXSIZE 384.0f*4.0f
#define BOXHEIGHT 256.0f*4.0f
#define BOXSTART -128.0f*4.0f

typedef struct
{
GLfloat x, y, z;
}SKYBOXVERTEX;
SKYBOXVERTEX pBoxList[ 8 ] =
{
{ -BOXSIZE, BOXSIZE, BOXSTART },
{ BOXSIZE, BOXSIZE, BOXSTART },
{ BOXSIZE, -BOXSIZE, BOXSTART },
{ -BOXSIZE, -BOXSIZE, BOXSTART },
{ -BOXSIZE, BOXSIZE, BOXSTART + BOXHEIGHT },
{ BOXSIZE, BOXSIZE, BOXSTART + BOXHEIGHT },
{ BOXSIZE, -BOXSIZE, BOXSTART + BOXHEIGHT },
{ -BOXSIZE, -BOXSIZE, BOXSTART + BOXHEIGHT },
};

#define nIndices (4 * 6)
WORD pIndices[ nIndices ] =
{
0, 1, 5, 4,
1, 2, 6, 5,
2, 3, 7, 6,
3, 0, 4, 7,
6, 7, 4, 5,
1, 0, 3, 2
};

[Zara]

On Fri, 14 Oct 2005 10:14:27 +0200, Michael Sgier <sg***@nospam.ch>
wrote:

Hello
what's going on here and some basic questions:
- define...unfortunately i haven't found it in my book so what exactly
does this?
- then SKYBOXVERTEX is declared...i understand the first struct but i
can only
guess what's going on from here on: SKYBOXVERTEX pBoxList[ 8 ] =
- I get the error: `WORD' undeclared (first use this function) Why? and
how shall I do it correctly?
THANKS and regards
Michael
#define BOXSIZE 384.0f*4.0f From now on, if BOZSIZE appears, substitute it by 384.0f*4.0f

#define BOXHEIGHT 256.0f*4.0f
#define BOXSTART -128.0f*4.0f

typedef struct
{
GLfloat x, y, z;
}SKYBOXVERTEX;
SKYBOXVERTES is an alias for a struct formed by three GLfloats called
x,y and z
SKYBOXVERTEX pBoxList[ 8 ] =
pBoxList is a sequence of eight structures of the kind defined above
{
{ -BOXSIZE, BOXSIZE, BOXSTART }, The first, pBoxList[0], has an x=-384.0f*4.0f; and y and z
=384.0f*4.0f { BOXSIZE, BOXSIZE, BOXSTART },
{ BOXSIZE, -BOXSIZE, BOXSTART },
{ -BOXSIZE, -BOXSIZE, BOXSTART },
{ -BOXSIZE, BOXSIZE, BOXSTART + BOXHEIGHT },
{ BOXSIZE, BOXSIZE, BOXSTART + BOXHEIGHT },
{ BOXSIZE, -BOXSIZE, BOXSTART + BOXHEIGHT },
{ -BOXSIZE, -BOXSIZE, BOXSTART + BOXHEIGHT },
};

#define nIndices (4 * 6) Form now in, everywhere there is nIndices written, (4*6) is meant WORD pIndices[ nIndices ] = pIndices is a sequence of 4*6=24 WORD { whose values are, beginning with the first,
pIndices[0]=0,pIndices[1]=1,pIndices[2]=5;.... 0, 1, 5, 4,
1, 2, 6, 5,
2, 3, 7, 6,
3, 0, 4, 7,
6, 7, 4, 5,
1, 0, 3, 2
};

You should have read a C++manual, ot the FAQ of this list.

[David White]

"Zara" <yo****@terra.es> wrote in message
news:ri********************************@4ax.com...

On Fri, 14 Oct 2005 10:14:27 +0200, Michael Sgier <sg***@nospam.ch>
wrote:
[snip]

- I get the error: `WORD' undeclared (first use this function) Why?
Probably because the WORD type is not defined anywhere.
and how shall I do it correctly?
WORD is not a native type so you need to define it ahead of where you use
it, and preferably before any structs as well. WORD is usually understood to
mean a 16-bit, or 2-byte, unsigned integer, so it's usual to typedef the
equivalent built-in type, e.g.,
typedef unsigned short WORD;

I've guessed that 'unsigned short' is 16 bits wide, but this depends on the
compiler.

Alternatively, forget WORD and just use a native type like unsigned int
instead, unless there's a reason it has to be a 16-bit type (highly unlikely
from what you've posted).
#define BOXHEIGHT 256.0f*4.0f
#define BOXSTART -128.0f*4.0f

typedef struct
{
GLfloat x, y, z;
}SKYBOXVERTEX;
[snip]
WORD pIndices[ nIndices ] =

You should have read a C++manual,
A C manual would be a better bet, I'd suggest. :-)
ot the FAQ of this list.

DW