synfig-core/trunk/src/modules/example/metaballs.cpp

   1 /* === S Y N F I G ========================================================= */
   2 /*!     \file metaballs.cpp
   3 **      \brief Implementation of the "Metaballs" layer
   4 **
   5 **      $Id$
   6 **
   7 **      \legal
   8 **      Copyright (c) 2002-2005 Robert B. Quattlebaum Jr., Adrian Bentley
   9 **
  10 **      This package is free software; you can redistribute it and/or
  11 **      modify it under the terms of the GNU General Public License as
  12 **      published by the Free Software Foundation; either version 2 of
  13 **      the License, or (at your option) any later version.
  14 **
  15 **      This package is distributed in the hope that it will be useful,
  16 **      but WITHOUT ANY WARRANTY; without even the implied warranty of
  17 **      MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  18 **      General Public License for more details.
  19 **      \endlegal
  20 */
  21 /* ========================================================================= */
  22
  23 /* === H E A D E R S ======================================================= */
  24
  25 #ifdef USING_PCH
  26 #       include "pch.h"
  27 #else
  28 #ifdef HAVE_CONFIG_H
  29 #       include <config.h>
  30 #endif
  31
  32 #include <synfig/string.h>
  33 #include <synfig/time.h>
  34 #include <synfig/context.h>
  35 #include <synfig/paramdesc.h>
  36 #include <synfig/renddesc.h>
  37 #include <synfig/surface.h>
  38 #include <synfig/value.h>
  39 #include <synfig/valuenode.h>
  40 #include <ETL/pen>
  41
  42 #include "metaballs.h"
  43
  44 #endif
  45
  46 /* === U S I N G =========================================================== */
  47
  48 using namespace etl;
  49 using namespace std;
  50 using namespace synfig;
  51
  52 /* === G L O B A L S ======================================================= */
  53
  54 SYNFIG_LAYER_INIT(Metaballs);
  55 SYNFIG_LAYER_SET_NAME(Metaballs,"metaballs");
  56 SYNFIG_LAYER_SET_LOCAL_NAME(Metaballs,N_("Metaballs"));
  57 SYNFIG_LAYER_SET_CATEGORY(Metaballs,N_("Example"));
  58 SYNFIG_LAYER_SET_VERSION(Metaballs,"0.1");
  59 SYNFIG_LAYER_SET_CVS_ID(Metaballs,"$Id$");
  60
  61 /* === P R O C E D U R E S ================================================= */
  62
  63 /* === M E T H O D S ======================================================= */
  64
  65 /* === E N T R Y P O I N T ================================================= */
  66
  67 Metaballs::Metaballs():
  68         Layer_Composite(1.0,Color::BLEND_STRAIGHT),
  69         color(Color::black())
  70 {
  71 }
  72
  73 bool
  74 Metaballs::set_param(const String & param, const ValueBase &value)
  75 {
  76         if(     param=="centers" && value.same_type_as(centers))
  77         {
  78                 centers = value;
  79                 return true;
  80         }
  81
  82         if(     param=="weights" && value.same_type_as(weights))
  83         {
  84                 weights = value;
  85                 return true;
  86         }
  87
  88         if(     param=="radii" && value.same_type_as(radii))
  89         {
  90                 radii = value;
  91                 return true;
  92         }
  93
  94         IMPORT(color);
  95         IMPORT(threshold);
  96
  97         return Layer_Composite::set_param(param,value);
  98 }
  99
 100 ValueBase
 101 Metaballs::get_param(const String &param)const
 102 {
 103         EXPORT(color);
 104
 105         EXPORT(radii);
 106         EXPORT(weights);
 107         EXPORT(centers);
 108         EXPORT(threshold);
 109
 110         EXPORT_NAME();
 111         EXPORT_VERSION();
 112
 113         return Layer_Composite::get_param(param);
 114 }
 115
 116 Layer::Vocab
 117 Metaballs::get_param_vocab()const
 118 {
 119         Layer::Vocab ret(Layer_Composite::get_param_vocab());
 120
 121         ret.push_back(ParamDesc("color")
 122                 .set_local_name(_("Color"))
 123         );
 124
 125         ret.push_back(ParamDesc("centers")
 126                 .set_local_name(_("Points"))
 127         );
 128
 129         ret.push_back(ParamDesc("radii")
 130                 .set_local_name(_("Radii"))
 131         );
 132
 133         ret.push_back(ParamDesc("weights")
 134                 .set_local_name(_("Weights"))
 135         );
 136
 137         ret.push_back(ParamDesc("threshold")
 138                 .set_local_name(_("Threshold"))
 139         );
 140
 141         return ret;
 142 }
 143
 144 static inline Real densityfunc(const synfig::Point &p, const synfig::Point &c, Real R)
 145 {
 146         const Real dx = p[0] - c[0];
 147         const Real dy = p[1] - c[1];
 148
 149         const Real n = (1 - (dx*dx + dy*dy)/(R*R));
 150         return (n*n*n);
 151
 152         /*
 153         f(d) = (1 - d^2)^3
 154         f'(d) = -6d * (1 - d^2)^2
 155
 156         could use this too...
 157         f(d) = (1 - d^2)^2
 158         f'(d) = -6d * (1 - d^2)
 159         */
 160 }
 161
 162 Real
 163 Metaballs::totaldensity(const Point &pos) const
 164 {
 165         Real density = 0;
 166
 167         //sum up weighted functions
 168         for(unsigned int i=0;i<centers.size();i++)
 169                 density += weights[i] * densityfunc(pos,centers[i], radii[i]);
 170
 171         return density;
 172 }
 173
 174 Color
 175 Metaballs::get_color(Context context, const Point &pos)const
 176 {
 177         if (totaldensity(pos) >= threshold)
 178                 return Color::blend(color,context.get_color(pos),get_amount(),get_blend_method());
 179         else
 180                 return context.get_color(pos);
 181 }
 182
 183 bool
 184 Metaballs::accelerated_render(Context context,Surface *surface,int quality, const RendDesc &renddesc, ProgressCallback *cb)const
 185 {
 186         // Width and Height of a pixel
 187         const Point br(renddesc.get_br()), tl(renddesc.get_tl());
 188         const int        w(renddesc.get_w()),   h(renddesc.get_h());
 189         const Real      pw(renddesc.get_pw()), ph(renddesc.get_ph());
 190
 191         SuperCallback supercb(cb,0,9000,10000);
 192
 193         Point pos(tl[0],tl[1]);
 194
 195         if(!context.accelerated_render(surface,quality,renddesc,&supercb))
 196         {
 197                 if(cb)cb->error(strprintf(__FILE__"%d: Accelerated Renderer Failure",__LINE__));
 198                 return false;
 199         }
 200
 201         for(int y = 0; y < h; y++, pos[1] += ph)
 202         {
 203                 pos[0] = tl[0];
 204                 for(int x = 0; x < w; x++, pos[0] += pw)
 205                         if (totaldensity(pos) >= threshold)
 206                                 (*surface)[y][x] = Color::blend(color,(*surface)[y][x],get_amount(),get_blend_method());
 207         }
 208
 209         // Mark our progress as finished
 210         if(cb && !cb->amount_complete(10000,10000))
 211                 return false;
 212
 213         return true;
 214 }