synfig-core/src/modules/mod_gradient/lineargradient.cpp

   1 /* === S Y N F I G ========================================================= */
   2 /*!     \file lineargradient.cpp
   3 **      \brief Implementation of the "Linear Gradient" 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 ** === N O T E S ===========================================================
  22 **
  23 ** ========================================================================= */
  24
  25 /* === H E A D E R S ======================================================= */
  26
  27 #ifdef USING_PCH
  28 #       include "pch.h"
  29 #else
  30 #ifdef HAVE_CONFIG_H
  31 #       include <config.h>
  32 #endif
  33
  34 #include "lineargradient.h"
  35
  36 #include <synfig/string.h>
  37 #include <synfig/time.h>
  38 #include <synfig/context.h>
  39 #include <synfig/paramdesc.h>
  40 #include <synfig/renddesc.h>
  41 #include <synfig/surface.h>
  42 #include <synfig/value.h>
  43 #include <synfig/valuenode.h>
  44
  45 #endif
  46
  47 /* === M A C R O S ========================================================= */
  48
  49 /* === G L O B A L S ======================================================= */
  50
  51 SYNFIG_LAYER_INIT(LinearGradient);
  52 SYNFIG_LAYER_SET_NAME(LinearGradient,"linear_gradient");
  53 SYNFIG_LAYER_SET_LOCAL_NAME(LinearGradient,N_("Linear Gradient"));
  54 SYNFIG_LAYER_SET_CATEGORY(LinearGradient,N_("Gradients"));
  55 SYNFIG_LAYER_SET_VERSION(LinearGradient,"0.0");
  56 SYNFIG_LAYER_SET_CVS_ID(LinearGradient,"$Id$");
  57
  58 /* === P R O C E D U R E S ================================================= */
  59
  60 /* === M E T H O D S ======================================================= */
  61
  62 inline void
  63 LinearGradient::sync()
  64 {
  65         diff=(p2-p1);
  66         const Real mag(diff.inv_mag());
  67         diff*=mag*mag;
  68 }
  69
  70
  71 LinearGradient::LinearGradient():
  72         Layer_Composite(1.0,Color::BLEND_COMPOSITE),
  73         p1(1,1),
  74         p2(-1,-1),
  75         gradient(Color::black(), Color::white()),
  76         loop(false),
  77         zigzag(false)
  78 {
  79         sync();
  80 }
  81
  82 inline Color
  83 LinearGradient::color_func(const Point &point, float supersample)const
  84 {
  85         Real dist(point*diff-p1*diff);
  86
  87         if(loop)
  88                 dist-=floor(dist);
  89
  90         if(zigzag)
  91         {
  92                 dist*=2.0;
  93                 supersample*=2.0;
  94                 if(dist>1)dist=2.0-dist;
  95         }
  96
  97         if(loop)
  98         {
  99                 if(dist+supersample*0.5>1.0)
 100                 {
 101                         float  left(supersample*0.5-(dist-1.0));
 102                         float right(supersample*0.5+(dist-1.0));
 103                         Color pool(gradient(1.0-(left*0.5),left).premult_alpha()*left/supersample);
 104                         if (zigzag) pool+=gradient(1.0-right*0.5,right).premult_alpha()*right/supersample;
 105                         else            pool+=gradient(right*0.5,right).premult_alpha()*right/supersample;
 106                         return pool.demult_alpha();
 107                 }
 108                 if(dist-supersample*0.5<0.0)
 109                 {
 110                         float  left(supersample*0.5-dist);
 111                         float right(supersample*0.5+dist);
 112                         Color pool(gradient(right*0.5,right).premult_alpha()*right/supersample);
 113                         if (zigzag) pool+=gradient(left*0.5,left).premult_alpha()*left/supersample;
 114                         else            pool+=gradient(1.0-left*0.5,left).premult_alpha()*left/supersample;
 115                         return pool.demult_alpha();
 116                 }
 117         }
 118         return gradient(dist,supersample);
 119 }
 120
 121 float
 122 LinearGradient::calc_supersample(const synfig::Point &/*x*/, float pw,float /*ph*/)const
 123 {
 124         return pw/(p2-p1).mag();
 125 }
 126
 127 synfig::Layer::Handle
 128 LinearGradient::hit_check(synfig::Context context, const synfig::Point &point)const
 129 {
 130         if(get_blend_method()==Color::BLEND_STRAIGHT && get_amount()>=0.5)
 131                 return const_cast<LinearGradient*>(this);
 132         if(get_amount()==0.0)
 133                 return context.hit_check(point);
 134         if((get_blend_method()==Color::BLEND_STRAIGHT || get_blend_method()==Color::BLEND_COMPOSITE) && color_func(point).get_a()>0.5)
 135                 return const_cast<LinearGradient*>(this);
 136         return context.hit_check(point);
 137 }
 138
 139 bool
 140 LinearGradient::set_param(const String & param, const ValueBase &value)
 141 {
 142         if(param=="p1" && value.same_type_as(p1))
 143         {
 144                 p1=value.get(p1);
 145                 sync();
 146                 return true;
 147         }
 148         if(param=="p2" && value.same_type_as(p2))
 149         {
 150                 p2=value.get(p2);
 151                 sync();
 152                 return true;
 153         }
 154         //IMPORT(p1);
 155         //IMPORT(p2);
 156
 157
 158         IMPORT(gradient);
 159         IMPORT(loop);
 160         IMPORT(zigzag);
 161         return Layer_Composite::set_param(param,value);
 162 }
 163
 164 ValueBase
 165 LinearGradient::get_param(const String & param)const
 166 {
 167         EXPORT(p1);
 168         EXPORT(p2);
 169         EXPORT(gradient);
 170         EXPORT(loop);
 171         EXPORT(zigzag);
 172
 173         EXPORT_NAME();
 174         EXPORT_VERSION();
 175
 176         return Layer_Composite::get_param(param);
 177 }
 178
 179 Layer::Vocab
 180 LinearGradient::get_param_vocab()const
 181 {
 182         Layer::Vocab ret(Layer_Composite::get_param_vocab());
 183
 184         ret.push_back(ParamDesc("p1")
 185                 .set_local_name(_("Point 1"))
 186                 .set_connect("p2")
 187         );
 188         ret.push_back(ParamDesc("p2")
 189                 .set_local_name(_("Point 2"))
 190         );
 191         ret.push_back(ParamDesc("gradient")
 192                 .set_local_name(_("Gradient"))
 193         );
 194         ret.push_back(ParamDesc("loop")
 195                 .set_local_name(_("Loop"))
 196         );
 197         ret.push_back(ParamDesc("zigzag")
 198                 .set_local_name(_("ZigZag"))
 199         );
 200
 201         return ret;
 202 }
 203
 204 Color
 205 LinearGradient::get_color(Context context, const Point &point)const
 206 {
 207         const Color color(color_func(point));
 208
 209         if(get_amount()==1.0 && get_blend_method()==Color::BLEND_STRAIGHT)
 210                 return color;
 211         else
 212                 return Color::blend(color,context.get_color(point),get_amount(),get_blend_method());
 213 }
 214
 215 bool
 216 LinearGradient::accelerated_render(Context context,Surface *surface,int quality, const RendDesc &renddesc, ProgressCallback *cb)const
 217 {
 218         SuperCallback supercb(cb,0,9500,10000);
 219
 220         if(get_amount()==1.0 && get_blend_method()==Color::BLEND_STRAIGHT)
 221         {
 222                 surface->set_wh(renddesc.get_w(),renddesc.get_h());
 223         }
 224         else
 225         {
 226                 if(!context.accelerated_render(surface,quality,renddesc,&supercb))
 227                         return false;
 228                 if(get_amount()==0)
 229                         return true;
 230         }
 231
 232
 233         int x,y;
 234
 235         Surface::pen pen(surface->begin());
 236         const Real pw(renddesc.get_pw()),ph(renddesc.get_ph());
 237         Point pos;
 238         Point tl(renddesc.get_tl());
 239         const int w(surface->get_w());
 240         const int h(surface->get_h());
 241
 242         if(get_amount()==1.0 && get_blend_method()==Color::BLEND_STRAIGHT)
 243         {
 244                 for(y=0,pos[1]=tl[1];y<h;y++,pen.inc_y(),pen.dec_x(x),pos[1]+=ph)
 245                         for(x=0,pos[0]=tl[0];x<w;x++,pen.inc_x(),pos[0]+=pw)
 246                                 pen.put_value(color_func(pos,calc_supersample(pos,pw,ph)));
 247         }
 248         else
 249         {
 250                 for(y=0,pos[1]=tl[1];y<h;y++,pen.inc_y(),pen.dec_x(x),pos[1]+=ph)
 251                         for(x=0,pos[0]=tl[0];x<w;x++,pen.inc_x(),pos[0]+=pw)
 252                                 pen.put_value(Color::blend(color_func(pos,calc_supersample(pos,pw,ph)),pen.get_value(),get_amount(),get_blend_method()));
 253         }
 254
 255         // Mark our progress as finished
 256         if(cb && !cb->amount_complete(10000,10000))
 257                 return false;
 258
 259         return true;
 260 }