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The way I do my loops which works fine for me is like this:

push ecx | mov ecx 0
L1: | push ecx | mov ecx 0
L2: | push ecx
...
pop ecx | inc ecx | cmp ecx xxx | jb L2<
pop ecx | inc ecx | cmp ecx xxx | jb L1<
pop ecx

You have a problem with the wonderful world of SpAsm? :grin:

Hey, good code :) I forgot inc/dec modified the flags... *sigh* it's late...

int FLAG_SIZE = 50

FlagVertices = new CUSTOMVERTEX [ NUM_FLAG_VERTICIES];



for (int ix = 0; ix < FLAG_SIZE+1; ix++)

     for (int iy = 0; iy < FLAG_SIZE+1; iy++)

     {

       FLOAT tu = ix/(FLOAT)FLAG_SIZE

       FLOAT tv = iy/(FLOAT)FLAG_SIZE



       FlagVertices[ix+iy*(FLAG_SIZE+1)].x = (float) (ix-FLAG_SIZE/2);

       FlagVertices[ix+iy*(FLAG_SIZE+1)].y = 3*(cos(iy)/3)+cos(ix/3)

       FlagVertices[ix+iy*(FLAG_SIZE+1)].z = iy -FLAG_SIZE/2

       FlagVertices[ix+iy*(FLAG_SIZE+1)].nx = 0.0

       FlagVertices[ix+iy*(FLAG_SIZE+1)].ny = 1.0

       FlagVertices[ix+iy*(FLAG_SIZE+1)].nz = 0.0

       FlagVertices[ix+iy*(FLAG_SIZE+1)].tu = (float)tu*4

       FlagVertices[ix+iy*(FLAG_SIZE+1)].tv = (float)tv*4      



      };

Ok, maybe I wasn't clear... I *didn't* want to know how to do a for loop

The problem with the code is:
FlagVertices

at ix = 0 and iy = 0 the FlagVertices[] would be equivalent to
FlagVertices[0]
at ix = 0 and iy = 1 the FlagVertices[] would be
FlagVertices[51]
at ix = 0 and iy = 2 the FlagVertices[] would be
FlagVertices[102]

after the first iteration of the loop the iy resets and the loop adds 1 to ix, SO:

at ix = 1 and iy = 0 the FlagVertices[] would be equivalent to
FlagVertices[1]
at ix = 1 and iy = 1 the FlagVertices[] would be
FlagVertices[52]
at ix = 1 and iy = 2 the FlagVertices[] would be
FlagVertices[103]

Do you see the patern?

Your loop fills up the code like this:

going across -> then shifts down

[0][0]
[0][0][0][0][0]
[0][0][0][0][0]

the c++ loop I described fills it up by going down and then shifting across
[0][0][0]
[0][0][0]
[0][0][0][0]
[0][0][0][0]

You can hopefully see why this loop is difficult to write:

So in conclusion I need to know how to advance the *pointer* to FlagVertices as in

mov eax, iy

mov edx, FLAG_SIZE +1

imul eax, edx

mov edx, size CUSTOMVERTEX

imul eax, edx

add esi, eax

or something like that... I'd appreciate any detailed responses on this issue (since I'm trying the best I can to convey the problem)

-=Sliver=-

I should say right off that I appreciate your help and time in this matter :) But I have 2 questions about it...

LOOPSIZE EQU 50

; for inner loop

iy EQU <ecx>

ix EQU <[esp]>

I've never seen this done before... Why do you do he 2 equ's with ix and iy if you don't seem to use them... and what would this be doing anyway... (again I've never seen this done)

	ASSUME esi:PTR CUSTOMVERTEX



	mov [esi + ebx].x,eax

Could this have been done by storing the number in just esi like:

; now we have the index in eax 

; have to multiple it by the array item size

	mov edx,sizeof CUSTOMVERTEX

	mul edx

	mov esi,eax



	ASSUME esi:PTR CUSTOMVERTEX



	mov [esi].x,eax

Or is their something special about this?

Thanks again bitRAKE and KEnny :)

-=Sliver=-

----EDIT----
Another problem arose... :(
I really thought you could do this:

push esi

ASSUME esi:PTR WORD

mov eax, OFFSET FlagIndices

mov esi, eax



mov ecx, 0

@OuterLoop1:

	push ecx



	mov ecx, 0

	@InnerLoop1:

		push ecx



		;FlagIndices[i++] = (ix+0) + (iy+1) * (FLAG_SIZE+1)

		fld ix

		fld iy

		fld1

		fadd

		fld FLAG_SIZEplusONE

		fmul

		fadd

		fstp [esi].WORD ; error here

		add esi, size WORD

Now I know WORD isn't a struct, but I just thought it would work... don't know why... can someone please give me a good way to change this code so I can skip through and store the code in the offset FlagIndices?

Thanks

Please excuse my naive nature... I'm C++ oriented and asm still
tends to be somewhat hard for me to wrap my mind around...

Ask and ye shall recieve... here is most of the C++ code that I'm
trying to port... (it's not very long in C++ as you can see)

----EDIT----

See below for all the code plus and example of what it's supposed to do

Yeap, you wanted WORD. ;)

You don't need to use the FPU for the FlagIndices loops - they are all integers. In fact an optimized solution would do both loops in parallel, but forget than until the codes working.

;	for(WORD i=0, ix=0; ix<FLAG_SIZE; ix++ )

;	for(WORD iy=0; iy<FLAG_SIZE; iy++ )

;	{

;		FlagIndices[i++] = (ix+0) + (iy+1)*(FLAG_SIZE+1);

;		FlagIndices[i++] = (ix+0) + (iy+0)*(FLAG_SIZE+1);

;		FlagIndices[i++] = (ix+1) + (iy+0)*(FLAG_SIZE+1);

;		FlagIndices[i++] = (ix+0) + (iy+1)*(FLAG_SIZE+1);

;		FlagIndices[i++] = (ix+1) + (iy+0)*(FLAG_SIZE+1);

;		FlagIndices[i++] = (ix+1) + (iy+1)*(FLAG_SIZE+1);

;	};



FLAG_SIZE EQU 50



; for inner loop

iy EQU <ecx>

ix EQU <[esp]>



	lea edi,FlagIndices

	mov ecx,FLAG_SIZE

L1:	push ecx



	mov ecx,FLAG_SIZE

L2:	mov eax,FLAG_SIZE

	mul iy ; this value is used through loop

	; line 1

	add eax,iy

	stosw

	; line 2

	sub eax,iy

	stosw

	; line 3

	add eax,ix

	stosw

	; line 4

	sub eax,ix

	add eax,iy

	stosw

	; line 5

	add eax,ix

	sub eax,iy

	stosw

	; line 6

	add eax,iy

	stosw



	dec ecx

	jns L2



	pop ecx

	dec ecx

	jns L1

This solution is by no mean optimal, but I think it works. ;) I think an optimized version would be a little bigger textwise than the C/C++ version. I want to see what VS.NET came up with for this? brb...even this is far better than what VS.NET came up with - I'm very disappointed. I think VC++ gets confused with the WORDs, too. :)

Edit: Opps, but it's fixed now - I think. ;)