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         Layer::Vocab voc(get_param_vocab());
  81         Layer::fill_static(voc);
  82 }
  83
  84 inline Color
  85 LinearGradient::color_func(const Point &point, float supersample)const
  86 {
  87         Real dist(point*diff-p1*diff);
  88
  89         if(loop)
  90                 dist-=floor(dist);
  91
  92         if(zigzag)
  93         {
  94                 dist*=2.0;
  95                 supersample*=2.0;
  96                 if(dist>1)dist=2.0-dist;
  97         }
  98
  99         if(loop)
 100         {
 101                 if(dist+supersample*0.5>1.0)
 102                 {
 103                         float  left(supersample*0.5-(dist-1.0));
 104                         float right(supersample*0.5+(dist-1.0));
 105                         Color pool(gradient(1.0-(left*0.5),left).premult_alpha()*left/supersample);
 106                         if (zigzag) pool+=gradient(1.0-right*0.5,right).premult_alpha()*right/supersample;
 107                         else            pool+=gradient(right*0.5,right).premult_alpha()*right/supersample;
 108                         return pool.demult_alpha();
 109                 }
 110                 if(dist-supersample*0.5<0.0)
 111                 {
 112                         float  left(supersample*0.5-dist);
 113                         float right(supersample*0.5+dist);
 114                         Color pool(gradient(right*0.5,right).premult_alpha()*right/supersample);
 115                         if (zigzag) pool+=gradient(left*0.5,left).premult_alpha()*left/supersample;
 116                         else            pool+=gradient(1.0-left*0.5,left).premult_alpha()*left/supersample;
 117                         return pool.demult_alpha();
 118                 }
 119         }
 120         return gradient(dist,supersample);
 121 }
 122
 123 float
 124 LinearGradient::calc_supersample(const synfig::Point &/*x*/, float pw,float /*ph*/)const
 125 {
 126         return pw/(p2-p1).mag();
 127 }
 128
 129 synfig::Layer::Handle
 130 LinearGradient::hit_check(synfig::Context context, const synfig::Point &point)const
 131 {
 132         if(get_blend_method()==Color::BLEND_STRAIGHT && get_amount()>=0.5)
 133                 return const_cast<LinearGradient*>(this);
 134         if(get_amount()==0.0)
 135                 return context.hit_check(point);
 136         if((get_blend_method()==Color::BLEND_STRAIGHT || get_blend_method()==Color::BLEND_COMPOSITE) && color_func(point).get_a()>0.5)
 137                 return const_cast<LinearGradient*>(this);
 138         return context.hit_check(point);
 139 }
 140
 141 bool
 142 LinearGradient::set_param(const String & param, const ValueBase &value)
 143 {
 144         if(param=="p1" && value.same_type_as(p1))
 145         {
 146                 p1=value.get(p1);
 147                 set_param_static(param, value.get_static());
 148                 sync();
 149                 return true;
 150         }
 151         if(param=="p2" && value.same_type_as(p2))
 152         {
 153                 p2=value.get(p2);
 154                 set_param_static(param, value.get_static());
 155                 sync();
 156                 return true;
 157         }
 158         //IMPORT(p1);
 159         //IMPORT(p2);
 160
 161
 162         IMPORT(gradient);
 163         IMPORT(loop);
 164         IMPORT(zigzag);
 165         return Layer_Composite::set_param(param,value);
 166 }
 167
 168 ValueBase
 169 LinearGradient::get_param(const String & param)const
 170 {
 171         EXPORT(p1);
 172         EXPORT(p2);
 173         EXPORT(gradient);
 174         EXPORT(loop);
 175         EXPORT(zigzag);
 176
 177         EXPORT_NAME();
 178         EXPORT_VERSION();
 179
 180         return Layer_Composite::get_param(param);
 181 }
 182
 183 Layer::Vocab
 184 LinearGradient::get_param_vocab()const
 185 {
 186         Layer::Vocab ret(Layer_Composite::get_param_vocab());
 187
 188         ret.push_back(ParamDesc("p1")
 189                 .set_local_name(_("Point 1"))
 190                 .set_connect("p2")
 191                 .set_description(_("Start point of the gradient"))
 192         );
 193         ret.push_back(ParamDesc("p2")
 194                 .set_local_name(_("Point 2"))
 195                 .set_description(_("End point of the gradient"))
 196         );
 197         ret.push_back(ParamDesc("gradient")
 198                 .set_local_name(_("Gradient"))
 199                 .set_description(_("Gradient to apply"))
 200         );
 201         ret.push_back(ParamDesc("loop")
 202                 .set_local_name(_("Loop"))
 203                 .set_description(_("When checked the gradient is looped"))
 204         );
 205         ret.push_back(ParamDesc("zigzag")
 206                 .set_local_name(_("ZigZag"))
 207                 .set_description(_("When checked the gradient is summetrical at the center"))
 208         );
 209
 210         return ret;
 211 }
 212
 213 Color
 214 LinearGradient::get_color(Context context, const Point &point)const
 215 {
 216         const Color color(color_func(point));
 217
 218         if(get_amount()==1.0 && get_blend_method()==Color::BLEND_STRAIGHT)
 219                 return color;
 220         else
 221                 return Color::blend(color,context.get_color(point),get_amount(),get_blend_method());
 222 }
 223
 224 bool
 225 LinearGradient::accelerated_render(Context context,Surface *surface,int quality, const RendDesc &renddesc, ProgressCallback *cb)const
 226 {
 227         SuperCallback supercb(cb,0,9500,10000);
 228
 229         if(get_amount()==1.0 && get_blend_method()==Color::BLEND_STRAIGHT)
 230         {
 231                 surface->set_wh(renddesc.get_w(),renddesc.get_h());
 232         }
 233         else
 234         {
 235                 if(!context.accelerated_render(surface,quality,renddesc,&supercb))
 236                         return false;
 237                 if(get_amount()==0)
 238                         return true;
 239         }
 240
 241
 242         int x,y;
 243
 244         Surface::pen pen(surface->begin());
 245         const Real pw(renddesc.get_pw()),ph(renddesc.get_ph());
 246         Point pos;
 247         Point tl(renddesc.get_tl());
 248         const int w(surface->get_w());
 249         const int h(surface->get_h());
 250
 251         if(get_amount()==1.0 && get_blend_method()==Color::BLEND_STRAIGHT)
 252         {
 253                 for(y=0,pos[1]=tl[1];y<h;y++,pen.inc_y(),pen.dec_x(x),pos[1]+=ph)
 254                         for(x=0,pos[0]=tl[0];x<w;x++,pen.inc_x(),pos[0]+=pw)
 255                                 pen.put_value(color_func(pos,calc_supersample(pos,pw,ph)));
 256         }
 257         else
 258         {
 259                 for(y=0,pos[1]=tl[1];y<h;y++,pen.inc_y(),pen.dec_x(x),pos[1]+=ph)
 260                         for(x=0,pos[0]=tl[0];x<w;x++,pen.inc_x(),pos[0]+=pw)
 261                                 pen.put_value(Color::blend(color_func(pos,calc_supersample(pos,pw,ph)),pen.get_value(),get_amount(),get_blend_method()));
 262         }
 263
 264         // Mark our progress as finished
 265         if(cb && !cb->amount_complete(10000,10000))
 266                 return false;
 267
 268         return true;
 269 }