Hi,
I started learning Lite-C some days ago and now I am working on a small test project. Everything was fine and working, but then I wanted to make the code more beautiful and readable by replacing everything that was seperate xyz coordinates before by VECTORS...a work of minutes as I thought.
Many confused hours later I realized that everytime I use vec math functions (vec_sub and so on), the source vector is overwritten.
So before every f*****g calculation I have to make copy of that vector to work with.
And those vector math functions really suck, vec_scale doesn't accept a negative factor for Example.
Before I start re-writing my whole script, is there a reason for using a vectors instead of a set of 3 variables for xyz?

please post example code of your problem.

#include <acknex.h>
#include <default.c>



VECTOR* P1={x=1;y=1;z=8;}
VECTOR* P2={x=7;y=4;z=5;}
VECTOR* P3={x=1;y=7;z=7;}
VECTOR* Result;

var Travel_Speed=1;
var Smoothness=1;


function bezier_spline(VECTOR* a, VECTOR* b, VECTOR* c, var Travel_Speed, var Smoothness)
{

VECTOR* Copy_a=a;
VECTOR* Copy_b=b;
VECTOR* Copy_c=c;

VECTOR* vec_a_b=vec_sub(Copy_b,a);
VECTOR* Copy_b = vec_set(Copy_b,b);
VECTOR* vec_b_c=vec_sub(Copy_c,b);
VECTOR* Copy_c = vec_set(Copy_c,c);
VECTOR* vec_a_c=vec_sub(Copy_c,a);
VECTOR* Copy_c = vec_set(Copy_c,c);


VECTOR* Copy_vec_a_b=vec_a_b;
VECTOR* Copy_vec_b_c=vec_b_c;
VECTOR* Copy_vec_a_c=vec_a_c;

VECTOR* Copy_vec_a_b=vec_set(Copy_vec_a_b, vec_a_b);
VECTOR* Copy_vec_b_c=vec_set(Copy_vec_b_c, vec_b_c);
VECTOR* Copy_vec_a_c=vec_set(Copy_vec_a_c, vec_a_c);


VECTOR* vec_b_h1;
VECTOR* vec_b_h2;


VECTOR* vec_b_h1=vec_scale(Copy_vec_a_c,0.5);
VECTOR* vec_b_h1=vec_inverse(vec_b_h1);




return(vec_b_h1);




}

function main()
{
Result=bezier_spline(P1,P2,P3,1,1);


}


PANEL* Anzeige=
{
digits (10, 10, 5.3, *, 1,Result[0]);
digits (10, 20, 5.3, *, 1,Result[1]);
digits (10, 30, 5.3, *, 1,Result[2]);




flags = VISIBLE;
}



This is an example of my code, I posted a wrong version before, sorry for that.

Everything works as supposed but is this really the way it's done?

I reworked everything so now it looks better,
but something doesn't work...

vec_b_h1 should be different from vec_b_h2 but isn't.

#include <acknex.h>
#include <default.c>



VECTOR* P1={x=1;y=1;z=8;}
VECTOR* P2={x=7;y=4;z=5;}
VECTOR* P3={x=1;y=7;z=7;}
VECTOR* Result;

var Travel_Speed=1;
var Smoothness=1;


function bezier_spline(VECTOR* a, VECTOR* b, VECTOR* c, var Travel_Speed, var Smoothness)
{

VECTOR* Copy_a=a;
VECTOR* Copy_b=b;
VECTOR* Copy_c=c;

VECTOR* vec_a_b=vec_sub(Copy_b,a);
vec_set(Copy_b,b);
VECTOR* vec_b_c=vec_sub(Copy_c,b);
vec_set(Copy_c,c);
VECTOR* vec_a_c=vec_sub(Copy_c,a);
vec_set(Copy_c,c);


VECTOR* Copy_vec_a_b=vec_a_b;
VECTOR* Copy_vec_b_c=vec_b_c;
VECTOR* Copy_vec_a_c=vec_a_c;


VECTOR* vec_b_h1=vec_scale(Copy_vec_a_c,0.5);
vec_inverse(vec_b_h1);
vec_set(Copy_vec_a_c, vec_a_c);

VECTOR* vec_b_h2=vec_scale(Copy_vec_a_c,0.5);



return(vec_b_h2);




}

function main()
{
Result=bezier_spline(P1,P2,P3,1,1);


}


PANEL* Anzeige=
{
digits (10, 10, 5.3, *, 1,Result[0]);
digits (10, 20, 5.3, *, 1,Result[1]);
digits (10, 30, 5.3, *, 1,Result[2]);




flags = VISIBLE;
}

ARRRGH... after checking my results nothing works at is it supposed.
I have to admit I don't understand the concept of those vector functions...
but I'll find out!

So, slowly but sure I'm going mad...

Here an example:

#include <acknex.h>
#include <default.c>



VECTOR* P1={x=1;y=1;z=8;}
VECTOR* P2={x=7;y=4;z=5;}
VECTOR* P3={x=1;y=7;z=7;}
VECTOR* Result;

var Travel_Speed=1;
var Smoothness=1;


function bezier_spline(VECTOR* a, VECTOR* b, VECTOR* c, var Travel_Speed, var Smoothness)
{

VECTOR* Copy_a=nullvector;
vec_set(Copy_a,a);
VECTOR* Copy_b=nullvector;
vec_set(Copy_b,b);
VECTOR* Copy_c=nullvector;
vec_set(Copy_c,c);

VECTOR* vec_a_b=nullvector;
vec_sub(Copy_b,a); //EXCLUDE THIS!!!

return(Copy_c);


}

function main()
{
Result=bezier_spline(P1,P2,P3,1,1);


}


PANEL* Anzeige=
{
digits (10, 10, 5.3, *, 1,Result[0]);
digits (10, 20, 5.3, *, 1,Result[1]);
digits (10, 30, 5.3, *, 1,Result[2]);




flags = VISIBLE;
}


What the hell has the marked line to do with vector Copy_c ????????????
If you exclude/include it the result will change!!!
I don't get it.

Ok, I need to know where you are now and what is happening or not happening.

Hello,
thanks for your interest - in my last posted script I have a function "bezier spline". This function doesn't do anything special, just a few vector calculations. Then it returns vector Copy_c which is printed by the panel.

The strange thing I don't understand is:
When I exclude/include the marked line the result will change - but this calculation seems to have absolutely nothing to do with vector Copy_c.

P.S. You can ignore the variables Travel_Speed and Smoothness.

Hello benni - your concept of copying vectors and not being able to scale negative values and so on is all nonsense, so the first thing you should do is throwing out all your copy_vectors.

Apart from that your code looks very wrong, for instance you are using local variables and then return them, but they cease to exist outside the function and thus all you return is garbage. I think the problem is not vector math, the problem is some fundamental misunderstanding of functions and pointers.

function whatever(VECTOR* a, VECTOR* b, VECTOR* c)
{
VECTOR result; // intermediate results
vec_set(result,b);
vec_sub(result,c);
vec_set(a,result);
// result is returned in a
}

Hope you get the idea...