Paraboloid of revolution

OK. Thank you.

I'm not the author of that tutorial but Eric Boez, see here:
https://www.ebsoft.fr/shop/en/19-fusion-c
That video is a good starting point :nishi:

Hi all,
Well, I know this might be well known, but just to sumarize what I found and to help anyone in the future (better jump directly into Fusion-C, I guess).
Maths functions are cumbersome in MSX-C, double and long (or XDOUBLE, SLONG) are not defined as types in the language like int, sqrt() is named xdsqrt(*ans, *number) and many more at mathmac.mac
Any way, this example shows what I mean. It seems when you call a math function the value at any pointer is cleanned, so I have to use a tmp variable. It worthed the fun, although.
P.s.: the includes are between < > not " "

#include "stdio.h"
#include "math.h"

main()
{
	/* 8 bytes long number in the form of a pointer */
	XDOUBLE a,b,ans,pi,tmp;
	/* Passing string formatted value to the pointer */
	atoxd(&a,"2.0");
	atoxd(&b,"3.0");
	atoxd(&pi,"3.141592");
	/**/
	printf("Number a = %3.2f\n",&a);
	printf("Number b = %3.2f\n",&b);	
	xdadd(&tmp,&a,&b);
	/* Square root*/
	xdsqrt(&ans,&a);
	printf("sqrt(a) = %3.2f\n",&ans);
	xdsqrt(&ans,&b);
	printf("sqrt(b) = %3.2f\n",&ans);
	/**/
	xdmul(&ans,&pi,&tmp);
	printf("5pi = %4.5f\n",&ans);
}