cal/cal/noise.cal

{ RCSid $Id$ }
{ 1-D Perlin Noise function }

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_1(xl,xd,xu) : hermite(
                                rand2a(xl),
                                rand2a(xu),
                                rand2b(xl),
                                rand2b(xu),
                                xd);

noise(x) : noise_1(floor(x),frac(x),ceil(x));
Revision:	1.3
Committed:	Wed Nov 21 17:45:45 2018 UTC (5 years, 6 months ago) by greg
Branch:	MAIN
CVS Tags:	rad5R4, rad5R3, HEAD
Changes since 1.2:	+10 -7 lines
Log Message:	Minor fixes/improvements
#	User	Rev	Content
1	greg	1.3	{ RCSid $Id$ }
2			{ 1-D Perlin Noise function }
3	greg	1.1
4	greg	1.3	frac(x):x-floor(x);
5
6			hermite(p0,p1,r0,r1,t) : p0 * ((2t-3)t*t+1) +
7	greg	1.1	p1 * (-2t+3)t*t +
8			r0 * (((t-2)t+1)t) +
9			r1 * ((t-1)tt);
10
11	greg	1.3	rand2a(x) : 1-2rand(.69692x);
12			rand2b(x) : 1-2rand(.05393x);
13	greg	1.1
14	greg	1.3	noise_1(xl,xd,xu) : hermite(
15	greg	1.1	rand2a(xl),
16			rand2a(xu),
17			rand2b(xl),
18			rand2b(xu),
19			xd);
20	greg	1.3
21			noise(x) : noise_1(floor(x),frac(x),ceil(x));