/* === S Y N F I G ========================================================= */
-/*! \file noise.cpp
+/*! \file mod_particle/random.cpp
** \brief blehh
**
-** $Id: random.cpp,v 1.1.1.1 2005/01/04 01:23:14 darco Exp $
+** $Id$
**
** \legal
-** Copyright (c) 2002 Robert B. Quattlebaum Jr.
+** Copyright (c) 2002-2005 Robert B. Quattlebaum Jr., Adrian Bentley
+** Copyright (c) 2007 Chris Moore
**
-** This software and associated documentation
-** are CONFIDENTIAL and PROPRIETARY property of
-** the above-mentioned copyright holder.
+** This package is free software; you can redistribute it and/or
+** modify it under the terms of the GNU General Public License as
+** published by the Free Software Foundation; either version 2 of
+** the License, or (at your option) any later version.
**
-** You may not copy, print, publish, or in any
-** other way distribute this software without
-** a prior written agreement with
-** the copyright holder.
+** This package is distributed in the hope that it will be useful,
+** but WITHOUT ANY WARRANTY; without even the implied warranty of
+** MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+** General Public License for more details.
** \endlegal
*/
/* ========================================================================= */
/* === M A C R O S ========================================================= */
+#define PI (3.1415927)
+
/* === G L O B A L S ======================================================= */
/* === P R O C E D U R E S ================================================= */
y_mask=rand()+rand()*RAND_MAX;
t_mask=rand()+rand()*RAND_MAX;
}
-
+
+// this picks one of the POOL_SIZE (256) preset values out of the pool
+// and scales it to be in the range (-1, 1). is that what it was
+// intended to do? the distribution is pretty terrible, too, with
+// some elements being picked a hundred times more often than others
float
Random::operator()(const int salt,const int x,const int y,const int t)const
{
const int salt_hash(pool_[salt&(POOL_SIZE-1)]);
-
+
int index(((x^x_mask)+(y^y_mask)*234672+(t^t_mask)*8439573)^salt_hash);
-
+
index+=index*(index/POOL_SIZE);
-
+
return (float(pool_[index&(POOL_SIZE-1)])/float(RAND_MAX))*2.0f-1.0f;
}
float
-Random::operator()(int smooth,int subseed,float xf,float yf,float tf)const
+Random::operator()(SmoothType smooth,int subseed,float xf,float yf,float tf)const
{
int x((int)floor(xf));
int y((int)floor(yf));
switch(smooth)
{
- case 4: // cubic
+ case SMOOTH_CUBIC: // cubic
{
#define f(j,i,k) ((*this)(subseed,i,j,k))
//Using catmull rom interpolation because it doesn't blur at all
+ // ( http://www.gamedev.net/reference/articles/article1497.asp )
//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
break;
- case 5: // Fast Spline (non-animated)
+ case SMOOTH_FAST_SPLINE: // Fast Spline (non-animated)
{
#define P(x) (((x)>0)?((x)*(x)*(x)):0.0f)
#define R(x) ( P(x+2) - 4.0f*P(x+1) + 6.0f*P(x) - 4.0f*P(x-1) )*(1.0f/6.0f)
#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)
+
+ case SMOOTH_SPLINE: // 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;
/*
#undef P
#undef R
- case 2: // Cosine
+ case SMOOTH_COSINE:
if((float)t==tf)
{
int x((int)floor(xf));
int y((int)floor(yf));
float a=xf-x;
float b=yf-y;
- a=(1.0f-cos(a*3.1415927))*0.5f;
- b=(1.0f-cos(b*3.1415927))*0.5f;
+ a=(1.0f-cos(a*PI))*0.5f;
+ b=(1.0f-cos(b*PI))*0.5f;
float c=1.0-a;
float d=1.0-b;
int x2=x+1,y2=y+1;
float b=yf-y;
float c=tf-t;
- a=(1.0f-cos(a*3.1415927))*0.5f;
- b=(1.0f-cos(b*3.1415927))*0.5f;
-
+ a=(1.0f-cos(a*PI))*0.5f;
+ b=(1.0f-cos(b*PI))*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;
-
+ //c=(1.0f-cos(c*PI))*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)+
(*this)(subseed,x,y2,t2)*(d*b*c)+
(*this)(subseed,x2,y2,t2)*(a*b*c);
}
- case 1: // Linear
+ case SMOOTH_LINEAR:
if((float)t==tf)
{
int x((int)floor(xf));
}
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)+
(*this)(subseed,x2,y2,t2)*(a*b*c);
}
default:
- case 0:
+ case SMOOTH_DEFAULT:
return (*this)(subseed,x,y,t);
}
}
projects / synfig.git / blobdiff