/* === S Y N F I G ========================================================= */
-/*! \file noise.cpp
+/*! \file mod_noise/random.cpp
** \brief blehh
**
-** $Id: random.cpp,v 1.6 2005/01/17 02:00:19 darco Exp $
+** $Id$
**
** \legal
** Copyright (c) 2002-2005 Robert B. Quattlebaum Jr., Adrian Bentley
+** Copyright (c) 2007 Chris Moore
**
** This package is free software; you can redistribute it and/or
** modify it under the terms of the GNU General Public License as
#endif
#include "random.h"
+#include <synfig/quick_rng.h>
#include <cmath>
#include <cstdlib>
#endif
-// A fast 32-bit linear congruential random number generator
-class quick_rng
-{
- unsigned long next;
-public:
- quick_rng(unsigned long seed):next(seed) { }
-
- void set_seed(unsigned long x)
- {
- next=x;
- }
-
- unsigned long i32()
- {
- static const unsigned long a(1664525);
- static const unsigned long c(1013904223);
-
- return next=next*a+c;
- }
-
- unsigned long i16()
- {
- return i32()>>16;
- }
-
- float f()
- {
- static const float m(int(65535));
-
- return float(i16())/m;
- }
-};
-
/* === M A C R O S ========================================================= */
#define PI (3.1415927)
{
seed_=x;
}
-
+
float
Random::operator()(const int salt,const int x,const int y,const int t)const
{
static const unsigned int b(11213);
static const unsigned int c(36979);
static const unsigned int d(31337);
-
+
quick_rng rng(
( static_cast<unsigned int>(x+y) * a ) ^
( static_cast<unsigned int>(y+t) * b ) ^
( static_cast<unsigned int>(t+x) * c ) ^
- ( static_cast<unsigned int>(seed_+salt) * d )
+ ( static_cast<unsigned int>(seed_+salt) * d )
);
-
+
return rng.f() * 2.0f - 1.0f;
}
//Using catmull rom interpolation because it doesn't blur at all
//bezier curve with intermediate ctrl pts: 0.5/3(p(i+1) - p(i-1)) and similar
float xfa [4], tfa[4];
-
+
//precalculate indices (all clamped) and offset
const int xa[] = {x-1,x,x+1,x+2};
-
+
const int ya[] = {y-1,y,y+1,y+2};
const int ta[] = {t-1,t,t+1,t+2};
-
+
const float dx(xf-x);
const float dy(yf-y);
const float dt(tf-t);
-
+
//figure polynomials for each point
- const float txf[] =
+ const float txf[] =
{
0.5*dx*(dx*(dx*(-1) + 2) - 1), //-t + 2t^2 -t^3
0.5*(dx*(dx*(3*dx - 5)) + 2), //2 - 5t^2 + 3t^3
0.5*dx*(dx*(-3*dx + 4) + 1), //t + 4t^2 - 3t^3
0.5*dx*dx*(dx-1) //-t^2 + t^3
};
-
- const float tyf[] =
+
+ const float tyf[] =
{
0.5*dy*(dy*(dy*(-1) + 2) - 1), //-t + 2t^2 -t^3
0.5*(dy*(dy*(3*dy - 5)) + 2), //2 - 5t^2 + 3t^3
0.5*dy*dy*(dy-1) //-t^2 + t^3
};
- const float ttf[] =
+ const float ttf[] =
{
0.5*dt*(dt*(dt*(-1) + 2) - 1), //-t + 2t^2 -t^3
0.5*(dt*(dt*(3*dt - 5)) + 2), //2 - 5t^2 + 3t^3
0.5*dt*(dt*(-3*dt + 4) + 1), //t + 4t^2 - 3t^3
0.5*dt*dt*(dt-1) //-t^2 + t^3
};
-
- //evaluate polynomial for each row
+
+ //evaluate polynomial for each row
for(int i = 0; i < 4; ++i)
{
for(int j = 0; j < 4; ++j)
}
xfa[i] = tfa[0]*txf[0] + tfa[1]*txf[1] + tfa[2]*txf[2] + tfa[3]*txf[3];
}
-
+
//return the cumulative column evaluation
return xfa[0]*tyf[0] + xfa[1]*tyf[1] + xfa[2]*tyf[2] + xfa[3]*tyf[3];
#undef f
#define FT(i,j,k) ((*this)(subseed,i+x,j+y,k+t)*(R((i)-a)*R(b-(j))*R((k)-c)))
#define Z(i,j) ret+=F(i,j)
#define ZT(i,j,k) ret+=FT(i,j,k)
-#define X(i,j) // placeholder... To make box more symetric
-#define XT(i,j,k) // placeholder... To make box more symetric
-
+#define X(i,j) // placeholder... To make box more symmetric
+#define XT(i,j,k) // placeholder... To make box more symmetric
+
float a(xf-x), b(yf-y);
-
+
// Interpolate
float ret(F(0,0));
Z(-1,-1); Z(-1, 0); Z(-1, 1); Z(-1, 2);
return ret;
}
-
+
case 3: // Spline (animated)
{
float a(xf-x), b(yf-y), c(tf-t);
-
+
// Interpolate
float ret(FT(0,0,0));
ZT(-1,-1,-1); ZT(-1, 0,-1); ZT(-1, 1,-1); ZT(-1, 2,-1);
ZT( 0,-1, 2); ZT( 0, 0, 2); ZT( 0, 1, 2); ZT( 0, 2, 2);
ZT( 1,-1, 2); ZT( 1, 0, 2); ZT( 1, 1, 2); ZT( 1, 2, 2);
ZT( 2,-1, 2); ZT( 2, 0, 2); ZT( 2, 1, 2); ZT( 2, 2, 2);
-
+
return ret;
/*
a=(1.0f-cos(a*3.1415927))*0.5f;
b=(1.0f-cos(b*3.1415927))*0.5f;
-
+
// We don't perform this on the time axis, otherwise we won't
// get smooth motion
//c=(1.0f-cos(c*3.1415927))*0.5f;
-
+
float d=1.0-a;
float e=1.0-b;
float f=1.0-c;
-
+
int x2=x+1,y2=y+1,t2=t+1;
-
+
return
(*this)(subseed,x,y,t)*(d*e*f)+
(*this)(subseed,x2,y,t)*(a*e*f)+
}
else
{
-
+
float a=xf-x;
float b=yf-y;
float c=tf-t;
-
+
float d=1.0-a;
float e=1.0-b;
float f=1.0-c;
-
+
int x2=x+1,y2=y+1,t2=t+1;
-
+
return
(*this)(subseed,x,y,t)*(d*e*f)+
(*this)(subseed,x2,y,t)*(a*e*f)+
projects / synfig.git / blobdiff