src/display/nr-filter-composite.cpp

   1 /*
   2  * feComposite filter effect renderer
   3  *
   4  * Authors:
   5  *   Niko Kiirala <niko@kiirala.com>
   6  *
   7  * Copyright (C) 2007 authors
   8  *
   9  * Released under GNU GPL, read the file 'COPYING' for more information
  10  */
  11
  12 #include <cmath>
  13
  14 #include "2geom/isnan.h"
  15 #include "sp-fecomposite.h"
  16 #include "display/nr-filter-composite.h"
  17 #include "display/nr-filter-pixops.h"
  18 #include "display/nr-filter-slot.h"
  19 #include "display/nr-filter-units.h"
  20 #include "display/nr-filter-utils.h"
  21 #include "libnr/nr-blit.h"
  22 #include "libnr/nr-pixblock.h"
  23 #include "libnr/nr-pixops.h"
  24 #include "libnr/nr-matrix.h"
  25
  26 inline void
  27 composite_over(unsigned char *r, unsigned char const *a, unsigned char const *b)
  28 {
  29     r[0] = a[0] + NR_NORMALIZE_21(b[0] * (255 - a[3]));
  30     r[1] = a[1] + NR_NORMALIZE_21(b[1] * (255 - a[3]));
  31     r[2] = a[2] + NR_NORMALIZE_21(b[2] * (255 - a[3]));
  32     r[3] = a[3] + NR_NORMALIZE_21(b[3] * (255 - a[3]));
  33 }
  34
  35 inline void
  36 composite_in(unsigned char *r, unsigned char const *a, unsigned char const *b)
  37 {
  38     r[0] = NR_NORMALIZE_21(a[0] * b[3]);
  39     r[1] = NR_NORMALIZE_21(a[1] * b[3]);
  40     r[2] = NR_NORMALIZE_21(a[2] * b[3]);
  41     r[3] = NR_NORMALIZE_21(a[3] * b[3]);
  42 }
  43
  44 inline void
  45 composite_out(unsigned char *r, unsigned char const *a, unsigned char const *b)
  46 {
  47     r[0] = NR_NORMALIZE_21(a[0] * (255 - b[3]));
  48     r[1] = NR_NORMALIZE_21(a[1] * (255 - b[3]));
  49     r[2] = NR_NORMALIZE_21(a[2] * (255 - b[3]));
  50     r[3] = NR_NORMALIZE_21(a[3] * (255 - b[3]));
  51 }
  52
  53 inline void
  54 composite_atop(unsigned char *r, unsigned char const *a, unsigned char const *b)
  55 {
  56     r[0] = NR_NORMALIZE_21(a[0] * b[3] + b[0] * (255 - a[3]));
  57     r[1] = NR_NORMALIZE_21(a[1] * b[3] + b[1] * (255 - a[3]));
  58     r[2] = NR_NORMALIZE_21(a[2] * b[3] + b[2] * (255 - a[3]));
  59     r[3] = b[3];
  60 }
  61
  62 inline void
  63 composite_xor(unsigned char *r, unsigned char const *a, unsigned char const *b)
  64 {
  65     r[0] = NR_NORMALIZE_21(a[0] * (255 - b[3]) + b[0] * (255 - a[3]));
  66     r[1] = NR_NORMALIZE_21(a[1] * (255 - b[3]) + b[1] * (255 - a[3]));
  67     r[2] = NR_NORMALIZE_21(a[2] * (255 - b[3]) + b[2] * (255 - a[3]));
  68     r[3] = NR_NORMALIZE_21(a[3] * (255 - b[3]) + b[3] * (255 - a[3]));
  69 }
  70
  71 // BUGBUG / TODO
  72 // This makes arithmetic compositing non re-entrant and non thread safe.
  73 static int arith_k1, arith_k2, arith_k3, arith_k4;
  74 inline void
  75 composite_arithmetic(unsigned char *r, unsigned char const *a, unsigned char const *b)
  76 {
  77     r[0] = NR_NORMALIZE_31(NR::clamp3(arith_k1 * a[0] * b[0]
  78                  + arith_k2 * a[0] + arith_k3 * b[0] + arith_k4));
  79     r[1] = NR_NORMALIZE_31(NR::clamp3(arith_k1 * a[1] * b[1]
  80                  + arith_k2 * a[1] + arith_k3 * b[1] + arith_k4));
  81     r[2] = NR_NORMALIZE_31(NR::clamp3(arith_k1 * a[2] * b[2]
  82                  + arith_k2 * a[2] + arith_k3 * b[2] + arith_k4));
  83     r[3] = NR_NORMALIZE_31(NR::clamp3(arith_k1 * a[3] * b[3]
  84                  + arith_k2 * a[3] + arith_k3 * b[3] + arith_k4));
  85 }
  86
  87 namespace NR {
  88
  89 FilterComposite::FilterComposite() :
  90     op(COMPOSITE_DEFAULT), k1(0), k2(0), k3(0), k4(0),
  91     _input2(NR::NR_FILTER_SLOT_NOT_SET)
  92 {}
  93
  94 FilterPrimitive * FilterComposite::create() {
  95     return new FilterComposite();
  96 }
  97
  98 FilterComposite::~FilterComposite()
  99 {}
 100
 101 int FilterComposite::render(FilterSlot &slot, FilterUnits const &/*units*/) {
 102     NRPixBlock *in1 = slot.get(_input);
 103     NRPixBlock *in2 = slot.get(_input2);
 104     NRPixBlock *original_in1 = in1;
 105     NRPixBlock *original_in2 = in2;
 106     NRPixBlock *out;
 107
 108     // Bail out if either one of source images is missing
 109     if (!in1 || !in2) {
 110         g_warning("Missing source image for feComposite (in=%d in2=%d)", _input, _input2);
 111         return 1;
 112     }
 113
 114     out = new NRPixBlock;
 115     NRRectL out_area;
 116     nr_rect_l_union(&out_area, &in1->area, &in2->area);
 117     nr_pixblock_setup_fast(out, NR_PIXBLOCK_MODE_R8G8B8A8P,
 118                            out_area.x0, out_area.y0, out_area.x1, out_area.y1,
 119                            true);
 120
 121     // Blending modes are defined for premultiplied RGBA values,
 122     // thus convert them to that format before blending
 123     if (in1->mode != NR_PIXBLOCK_MODE_R8G8B8A8P) {
 124         in1 = new NRPixBlock;
 125         nr_pixblock_setup_fast(in1, NR_PIXBLOCK_MODE_R8G8B8A8P,
 126                                original_in1->area.x0, original_in1->area.y0,
 127                                original_in1->area.x1, original_in1->area.y1,
 128                                false);
 129         nr_blit_pixblock_pixblock(in1, original_in1);
 130     }
 131     if (in2->mode != NR_PIXBLOCK_MODE_R8G8B8A8P) {
 132         in2 = new NRPixBlock;
 133         nr_pixblock_setup_fast(in2, NR_PIXBLOCK_MODE_R8G8B8A8P,
 134                                original_in2->area.x0, original_in2->area.y0,
 135                                original_in2->area.x1, original_in2->area.y1,
 136                                false);
 137         nr_blit_pixblock_pixblock(in2, original_in2);
 138     }
 139
 140     /* pixops_mix is defined in display/nr-filter-pixops.h
 141      * It mixes the two input images with the function given as template
 142      * and places the result in output image.
 143      */
 144     switch (op) {
 145         case COMPOSITE_IN:
 146             pixops_mix<composite_in>(*out, *in1, *in2);
 147             break;
 148         case COMPOSITE_OUT:
 149             pixops_mix<composite_out>(*out, *in1, *in2);
 150             break;
 151         case COMPOSITE_ATOP:
 152             pixops_mix<composite_atop>(*out, *in1, *in2);
 153             break;
 154         case COMPOSITE_XOR:
 155             pixops_mix<composite_xor>(*out, *in1, *in2);
 156             break;
 157         case COMPOSITE_ARITHMETIC:
 158             arith_k1 = (int)(k1 * 255);
 159             arith_k2 = (int)(k2 * 255 * 255);
 160             arith_k3 = (int)(k3 * 255 * 255);
 161             arith_k4 = (int)(k4 * 255 * 255 * 255);
 162             pixops_mix<composite_arithmetic>(*out, *in1, *in2);
 163             break;
 164         case COMPOSITE_DEFAULT:
 165         case COMPOSITE_OVER:
 166         default:
 167             pixops_mix<composite_over>(*out, *in1, *in2);
 168             break;
 169     }
 170
 171     if (in1 != original_in1) {
 172         nr_pixblock_release(in1);
 173         delete in1;
 174     }
 175     if (in2 != original_in2) {
 176         nr_pixblock_release(in2);
 177         delete in2;
 178     }
 179
 180     out->empty = FALSE;
 181     slot.set(_output, out);
 182
 183     return 0;
 184 }
 185
 186 void FilterComposite::set_input(int input) {
 187     _input = input;
 188 }
 189
 190 void FilterComposite::set_input(int input, int slot) {
 191     if (input == 0) _input = slot;
 192     if (input == 1) _input2 = slot;
 193 }
 194
 195 void FilterComposite::set_operator(FeCompositeOperator op) {
 196     if (op == COMPOSITE_DEFAULT) {
 197         this->op = COMPOSITE_OVER;
 198     } else if (op == COMPOSITE_OVER ||
 199                op == COMPOSITE_IN ||
 200                op == COMPOSITE_OUT ||
 201                op == COMPOSITE_ATOP ||
 202                op == COMPOSITE_XOR ||
 203                op == COMPOSITE_ARITHMETIC)
 204     {
 205         this->op = op;
 206     }
 207 }
 208
 209 void FilterComposite::set_arithmetic(double k1, double k2, double k3, double k4) {
 210     if (!IS_FINITE(k1) || !IS_FINITE(k2) || !IS_FINITE(k3) || !IS_FINITE(k4)) {
 211         g_warning("Non-finite parameter for feComposite arithmetic operator");
 212         return;
 213     }
 214     this->k1 = k1;
 215     this->k2 = k2;
 216     this->k3 = k3;
 217     this->k4 = k4;
 218 }
 219
 220 } /* namespace NR */
 221
 222 /*
 223   Local Variables:
 224   mode:c++
 225   c-file-style:"stroustrup"
 226   c-file-offsets:((innamespace . 0)(inline-open . 0)(case-label . +))
 227   indent-tabs-mode:nil
 228   fill-column:99
 229   End:
 230 */
 231 // vim: filetype=cpp:expandtab:shiftwidth=4:tabstop=8:softtabstop=4:encoding=utf-8:textwidth=99 :