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 "filters/composite.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
  25 inline void
  26 composite_over(unsigned char *r, unsigned char const *a, unsigned char const *b)
  27 {
  28     r[0] = NR_COMPOSEPPP_1111(a[0],a[3],b[0]);
  29     r[1] = NR_COMPOSEPPP_1111(a[1],a[3],b[1]);
  30     r[2] = NR_COMPOSEPPP_1111(a[2],a[3],b[2]);
  31     r[3] = NR_COMPOSEPPP_1111(a[3],a[3],b[3]);
  32 }
  33
  34 inline void
  35 composite_in(unsigned char *r, unsigned char const *a, unsigned char const *b)
  36 {
  37     r[0] = NR_NORMALIZE_21(a[0] * b[3]);
  38     r[1] = NR_NORMALIZE_21(a[1] * b[3]);
  39     r[2] = NR_NORMALIZE_21(a[2] * b[3]);
  40     r[3] = NR_NORMALIZE_21(a[3] * b[3]);
  41 }
  42
  43 inline void
  44 composite_out(unsigned char *r, unsigned char const *a, unsigned char const *b)
  45 {
  46     r[0] = NR_NORMALIZE_21(a[0] * (255 - b[3]));
  47     r[1] = NR_NORMALIZE_21(a[1] * (255 - b[3]));
  48     r[2] = NR_NORMALIZE_21(a[2] * (255 - b[3]));
  49     r[3] = NR_NORMALIZE_21(a[3] * (255 - b[3]));
  50 }
  51
  52 inline void
  53 composite_atop(unsigned char *r, unsigned char const *a, unsigned char const *b)
  54 {
  55     r[0] = NR_NORMALIZE_21(a[0] * b[3] + b[0] * (255 - a[3]));
  56     r[1] = NR_NORMALIZE_21(a[1] * b[3] + b[1] * (255 - a[3]));
  57     r[2] = NR_NORMALIZE_21(a[2] * b[3] + b[2] * (255 - a[3]));
  58     r[3] = b[3];
  59 }
  60
  61 inline void
  62 composite_xor(unsigned char *r, unsigned char const *a, unsigned char const *b)
  63 {
  64     r[0] = NR_NORMALIZE_21(a[0] * (255 - b[3]) + b[0] * (255 - a[3]));
  65     r[1] = NR_NORMALIZE_21(a[1] * (255 - b[3]) + b[1] * (255 - a[3]));
  66     r[2] = NR_NORMALIZE_21(a[2] * (255 - b[3]) + b[2] * (255 - a[3]));
  67     r[3] = NR_NORMALIZE_21(a[3] * (255 - b[3]) + b[3] * (255 - a[3]));
  68 }
  69
  70 // BUGBUG / TODO
  71 // This makes arithmetic compositing non re-entrant and non thread safe.
  72 static int arith_k1, arith_k2, arith_k3, arith_k4;
  73 inline void
  74 composite_arithmetic(unsigned char *r, unsigned char const *a, unsigned char const *b)
  75 {
  76     using Inkscape::Filters::clamp3;
  77     r[0] = NR_NORMALIZE_31(clamp3(arith_k1 * a[0] * b[0]
  78                  + arith_k2 * a[0] + arith_k3 * b[0] + arith_k4));
  79     r[1] = NR_NORMALIZE_31(clamp3(arith_k1 * a[1] * b[1]
  80                  + arith_k2 * a[1] + arith_k3 * b[1] + arith_k4));
  81     r[2] = NR_NORMALIZE_31(clamp3(arith_k1 * a[2] * b[2]
  82                  + arith_k2 * a[2] + arith_k3 * b[2] + arith_k4));
  83     r[3] = NR_NORMALIZE_31(clamp3(arith_k1 * a[3] * b[3]
  84                  + arith_k2 * a[3] + arith_k3 * b[3] + arith_k4));
  85 }
  86
  87 namespace Inkscape {
  88 namespace Filters {
  89
  90 FilterComposite::FilterComposite() :
  91     op(COMPOSITE_DEFAULT), k1(0), k2(0), k3(0), k4(0),
  92     _input2(Inkscape::Filters::NR_FILTER_SLOT_NOT_SET)
  93 {}
  94
  95 FilterPrimitive * FilterComposite::create() {
  96     return new FilterComposite();
  97 }
  98
  99 FilterComposite::~FilterComposite()
 100 {}
 101
 102 int FilterComposite::render(FilterSlot &slot, FilterUnits const &/*units*/) {
 103     NRPixBlock *in1 = slot.get(_input);
 104     NRPixBlock *in2 = slot.get(_input2);
 105     NRPixBlock *original_in1 = in1;
 106     NRPixBlock *original_in2 = in2;
 107     NRPixBlock *out;
 108
 109     // Bail out if either one of source images is missing
 110     if (!in1 || !in2) {
 111         g_warning("Missing source image for feComposite (in=%d in2=%d)", _input, _input2);
 112         return 1;
 113     }
 114
 115     out = new NRPixBlock;
 116     NRRectL out_area;
 117     nr_rect_l_union(&out_area, &in1->area, &in2->area);
 118     nr_pixblock_setup_fast(out, NR_PIXBLOCK_MODE_R8G8B8A8P,
 119                            out_area.x0, out_area.y0, out_area.x1, out_area.y1,
 120                            true);
 121
 122     // Blending modes are defined for premultiplied RGBA values,
 123     // thus convert them to that format before blending
 124     if (in1->mode != NR_PIXBLOCK_MODE_R8G8B8A8P) {
 125         in1 = nr_pixblock_new_fast(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 = nr_pixblock_new_fast(NR_PIXBLOCK_MODE_R8G8B8A8P,
 133                                    original_in2->area.x0, original_in2->area.y0,
 134                                    original_in2->area.x1, original_in2->area.y1,
 135                                    false);
 136         nr_blit_pixblock_pixblock(in2, original_in2);
 137     }
 138
 139     /* pixops_mix is defined in display/nr-filter-pixops.h
 140      * It mixes the two input images with the function given as template
 141      * and places the result in output image.
 142      */
 143     switch (op) {
 144         case COMPOSITE_IN:
 145             pixops_mix<composite_in>(*out, *in1, *in2);
 146             break;
 147         case COMPOSITE_OUT:
 148             pixops_mix<composite_out>(*out, *in1, *in2);
 149             break;
 150         case COMPOSITE_ATOP:
 151             pixops_mix<composite_atop>(*out, *in1, *in2);
 152             break;
 153         case COMPOSITE_XOR:
 154             pixops_mix<composite_xor>(*out, *in1, *in2);
 155             break;
 156         case COMPOSITE_ARITHMETIC:
 157             arith_k1 = (int)round(k1 * 255);
 158             arith_k2 = (int)round(k2 * 255 * 255);
 159             arith_k3 = (int)round(k3 * 255 * 255);
 160             arith_k4 = (int)round(k4 * 255 * 255 * 255);
 161             pixops_mix<composite_arithmetic>(*out, *in1, *in2);
 162             break;
 163         case COMPOSITE_DEFAULT:
 164         case COMPOSITE_OVER:
 165         default:
 166             pixops_mix<composite_over>(*out, *in1, *in2);
 167             break;
 168     }
 169
 170     if (in1 != original_in1) {
 171         nr_pixblock_free(in1);
 172     }
 173     if (in2 != original_in2) {
 174         nr_pixblock_free(in2);
 175     }
 176
 177     out->empty = FALSE;
 178     slot.set(_output, out);
 179
 180     return 0;
 181 }
 182
 183 void FilterComposite::set_input(int input) {
 184     _input = input;
 185 }
 186
 187 void FilterComposite::set_input(int input, int slot) {
 188     if (input == 0) _input = slot;
 189     if (input == 1) _input2 = slot;
 190 }
 191
 192 void FilterComposite::set_operator(FeCompositeOperator op) {
 193     if (op == COMPOSITE_DEFAULT) {
 194         this->op = COMPOSITE_OVER;
 195     } else if (op == COMPOSITE_OVER ||
 196                op == COMPOSITE_IN ||
 197                op == COMPOSITE_OUT ||
 198                op == COMPOSITE_ATOP ||
 199                op == COMPOSITE_XOR ||
 200                op == COMPOSITE_ARITHMETIC)
 201     {
 202         this->op = op;
 203     }
 204 }
 205
 206 void FilterComposite::set_arithmetic(double k1, double k2, double k3, double k4) {
 207     if (!IS_FINITE(k1) || !IS_FINITE(k2) || !IS_FINITE(k3) || !IS_FINITE(k4)) {
 208         g_warning("Non-finite parameter for feComposite arithmetic operator");
 209         return;
 210     }
 211     this->k1 = k1;
 212     this->k2 = k2;
 213     this->k3 = k3;
 214     this->k4 = k4;
 215 }
 216
 217 } /* namespace Filters */
 218 } /* namespace Inkscape */
 219
 220 /*
 221   Local Variables:
 222   mode:c++
 223   c-file-style:"stroustrup"
 224   c-file-offsets:((innamespace . 0)(inline-open . 0)(case-label . +))
 225   indent-tabs-mode:nil
 226   fill-column:99
 227   End:
 228 */
 229 // vim: filetype=cpp:expandtab:shiftwidth=4:tabstop=8:softtabstop=4:fileencoding=utf-8:textwidth=99 :