basic pointer question

[tigital]

ok,

...it's time I need to admit I'm a self-taught hobby programmer, cuz 
I've run into (perhaps) a basic problem that I can't seem to figure 
out, having to do with pointers and such...

...here is the original version of the function:
void moff_defpoints(ubyte * p)
{
	int n;
	int nverts = w(p+8);
	int offset = w(p+16);

	ubyte * normcount = p+20;
         vector *src = vp(p+offset);

	Assert( nverts < MAX_POLYGON_VECS );
	// Assert( nnorms < MAX_POLYGON_NORMS );

	for (n=0; n<nverts; n++ )	{

             Interp_verts[n] = src;
             src += normcount[n]+1;
	}
}
...this seems to step through a set of vertex vectors (xyz.x,y,z)and 
assign them to an externally declared global vector 
"Interp_verts[n]"...ByteSwapping needs to be done on all data coming 
from the passed in pointer "p", so I initially tried swapping the 
x,y, and z floats passed into the "src" vector by doing src->xyz.x = 
LoadLEFloat( &src->xyz.x );

...then I noticed that by doing this, I'm actually changing the value 
in the passed in pointer, and so future references get swapped 
multiple times, which isn't good!

So, I tried to create a local "buffer" vector that would hold the 
swapped floats, put them into a buffer vector, then pass that to the 
global vector Interp_verts[n]...but this isn't happening, and I'm not 
sure where I've gone wrong?  Can someone get me straight on this?

void moff_defpoints(ubyte * p)
{
	int n;
	int nverts = SDL_SwapLE32( w(p+8));
	int offset = SDL_SwapLE32( w(p+16));
         //int nverts = w(p+8);
         //int offset = w(p+16);
         float	srcx, srcy, srcz;
         vector *tmp;

	ubyte * normcount = p+20;
         vector *src = vp(p+offset);

	Assert( nverts < MAX_POLYGON_VECS );
	// Assert( nnorms < MAX_POLYGON_NORMS );

	for (n=0; n<nverts; n++ )	{
             srcx = LoadLEFloat( &src->xyz.x );
             srcy = LoadLEFloat( &src->xyz.y );
             srcz = LoadLEFloat( &src->xyz.z );
             tmp->xyz.x = srcx;
             tmp->xyz.y = srcy;
             tmp->xyz.z = srcz;

             //Interp_verts[n] = src;
             Interp_verts[n] = tmp;
             normcount[n] = SDL_SwapLE16( normcount[n] );

             src += normcount[n]+1;
	}
}

Tanx,
jamie
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