--- /dev/null
+/* === S Y N F I G ========================================================= */
+/*! \file metaballs.cpp
+** \brief Implements metaballs
+**
+** $Id$
+**
+** \legal
+** Copyright (c) 2002-2005 Robert B. Quattlebaum Jr., Adrian Bentley
+**
+** 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.
+**
+** 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
+*/
+/* ========================================================================= */
+
+/* === H E A D E R S ======================================================= */
+
+#ifdef USING_PCH
+# include "pch.h"
+#else
+#ifdef HAVE_CONFIG_H
+# include <config.h>
+#endif
+
+#include <synfig/string.h>
+#include <synfig/time.h>
+#include <synfig/context.h>
+#include <synfig/paramdesc.h>
+#include <synfig/renddesc.h>
+#include <synfig/surface.h>
+#include <synfig/value.h>
+#include <synfig/valuenode.h>
+#include <ETL/pen>
+
+#include "metaballs.h"
+
+#endif
+
+/* === U S I N G =========================================================== */
+
+using namespace etl;
+using namespace std;
+using namespace synfig;
+
+/* === G L O B A L S ======================================================= */
+
+SYNFIG_LAYER_INIT(Metaballs);
+SYNFIG_LAYER_SET_NAME(Metaballs,"metaballs");
+SYNFIG_LAYER_SET_LOCAL_NAME(Metaballs,_("Metaballs"));
+SYNFIG_LAYER_SET_CATEGORY(Metaballs,_("Default"));
+SYNFIG_LAYER_SET_VERSION(Metaballs,"0.1");
+SYNFIG_LAYER_SET_CVS_ID(Metaballs,"$Id$");
+
+/* === P R O C E D U R E S ================================================= */
+
+/* === M E T H O D S ======================================================= */
+
+/* === E N T R Y P O I N T ================================================= */
+
+Metaballs::Metaballs():
+ Layer_Composite(1.0,Color::BLEND_STRAIGHT),
+ color(Color::black())
+{
+}
+
+bool
+Metaballs::set_param(const String & param, const ValueBase &value)
+{
+ if( param=="centers" && value.same_as(centers))
+ {
+ centers = value;
+ return true;
+ }
+
+ if( param=="weights" && value.same_as(weights))
+ {
+ weights = value;
+ return true;
+ }
+
+ if( param=="radii" && value.same_as(radii))
+ {
+ radii = value;
+ return true;
+ }
+
+ IMPORT(color);
+ IMPORT(threshold);
+
+ return Layer_Composite::set_param(param,value);
+}
+
+ValueBase
+Metaballs::get_param(const String ¶m)const
+{
+ EXPORT(color);
+
+ EXPORT(radii);
+ EXPORT(weights);
+ EXPORT(centers);
+ EXPORT(threshold);
+
+ EXPORT_NAME();
+ EXPORT_VERSION();
+
+ return Layer_Composite::get_param(param);
+}
+
+Layer::Vocab
+Metaballs::get_param_vocab()const
+{
+ Layer::Vocab ret(Layer_Composite::get_param_vocab());
+
+ ret.push_back(ParamDesc("color")
+ .set_local_name(_("Color"))
+ );
+
+ ret.push_back(ParamDesc("centers")
+ .set_local_name(_("Points"))
+ );
+
+ ret.push_back(ParamDesc("radii")
+ .set_local_name(_("Radii"))
+ );
+
+ ret.push_back(ParamDesc("weights")
+ .set_local_name(_("Weights"))
+ );
+
+ ret.push_back(ParamDesc("threshold")
+ .set_local_name(_("Threshold"))
+ );
+
+ return ret;
+}
+
+static inline Real densityfunc(const synfig::Point &p, const synfig::Point &c, Real R)
+{
+ const Real dx = p[0] - c[0];
+ const Real dy = p[1] - c[1];
+
+ const Real n = (1 - (dx*dx + dy*dy)/(R*R));
+ return (n*n*n);
+
+ /*
+ f(d) = (1 - d^2)^3
+ f'(d) = -6d * (1 - d^2)^2
+
+ could use this too...
+ f(d) = (1 - d^2)^2
+ f'(d) = -6d * (1 - d^2)
+ */
+}
+
+Real
+Metaballs::totaldensity(const Point &pos) const
+{
+ Real density = 0;
+
+ //sum up weighted functions
+ for(unsigned int i=0;i<centers.size();i++)
+ {
+ density += weights[i] * densityfunc(pos,centers[i], radii[i]);
+ }
+
+ return density;
+}
+
+Color
+Metaballs::get_color(Context context, const Point &pos)const
+{
+ Real dens = totaldensity(pos);
+
+ if(dens >= threshold)
+ return color;
+ else
+ return context.get_color(pos);
+}
+
+bool
+Metaballs::accelerated_render(Context context,Surface *surface,int quality, const RendDesc &renddesc, ProgressCallback *cb)const
+{
+ // Width and Height of a pixel
+ const Point br(renddesc.get_br()),
+ tl(renddesc.get_tl());
+
+ const int w = renddesc.get_w(),
+ h = renddesc.get_h();
+
+ Real pw = renddesc.get_pw();
+ Real ph = renddesc.get_ph();
+
+ SuperCallback supercb(cb,0,9000,10000);
+
+ if(!context.accelerated_render(surface,quality,renddesc,&supercb))
+ {
+ if(cb)cb->error(strprintf(__FILE__"%d: Accelerated Renderer Failure",__LINE__));
+ return false;
+ }
+
+ Point pos(tl[0],tl[1]);
+
+ Real dens;
+
+ if(!context.accelerated_render(surface,quality,renddesc,&supercb))
+ {
+ if(cb)cb->error(strprintf(__FILE__"%d: Accelerated Renderer Failure",__LINE__));
+ return false;
+ }
+
+ for(int y = 0; y < h; y++, pos[1] += ph)
+ {
+ pos[0] = tl[0];
+ for(int x = 0; x < w; x++, pos[0] += pw)
+ {
+ dens = totaldensity(pos);
+
+ if(dens >= threshold)
+ {
+ (*surface)[y][x] = Color::blend(color,(*surface)[y][x],get_amount(),get_blend_method());
+ }
+ }
+ }
+
+ // Mark our progress as finished
+ if(cb && !cb->amount_complete(10000,10000))
+ return false;
+
+ return true;
+}