cal/cal/noise.cal

frac(x)=x-floor(x);

hermite(p0,p1,r0,r1,t) =        p0 * ((2*t-3)*t*t+1) +
                                p1 * (-2*t+3)*t*t +
                                r0 * (((t-2)*t+1)*t) +
                                r1 * ((t-1)*t*t);

rand2a(x) = 1-2*rand(.69692*x);
rand2b(x) = 1-2*rand(.05393*x);

noise(x,y) = noise_1(floor(x),frac(x),ceil(x));

noise_1(xl,xd,xu) = hermite(
                                rand2a(xl),
                                rand2a(xu),
                                rand2b(xl),
                                rand2b(xu),
                                xd);
Revision:	1.1
Committed:	Sat Feb 22 02:07:21 2003 UTC (21 years, 2 months ago) by greg
Branch:	MAIN
CVS Tags:	rad3R7P2, rad3R7P1, rad4R0, rad3R5, rad3R6, rad3R6P1, rad3R8, rad3R9
Log Message:	Changes and check-in for 3.5 release Includes new source files and modifications not recorded for many years See ray/doc/notes/ReleaseNotes for notes between 3.1 and 3.5 release
#	User	Rev	Content
1	greg	1.1	frac(x)=x-floor(x);
2
3			hermite(p0,p1,r0,r1,t) = p0 * ((2t-3)t*t+1) +
4			p1 * (-2t+3)t*t +
5			r0 * (((t-2)t+1)t) +
6			r1 * ((t-1)tt);
7
8			rand2a(x) = 1-2rand(.69692x);
9			rand2b(x) = 1-2rand(.05393x);
10
11			noise(x,y) = noise_1(floor(x),frac(x),ceil(x));
12
13			noise_1(xl,xd,xu) = hermite(
14			rand2a(xl),
15			rand2a(xu),
16			rand2b(xl),
17			rand2b(xu),
18			xd);