1 /*
2 * feMerge 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 */
12 #include <cmath>
13 #include <vector>
15 #include "isnan.h"
16 #include "sp-femerge.h"
17 #include "display/nr-filter-merge.h"
18 #include "display/nr-filter-pixops.h"
19 #include "display/nr-filter-slot.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"
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 }
35 namespace NR {
37 FilterMerge::FilterMerge() :
38 _input_image(1, NR_FILTER_SLOT_NOT_SET)
39 {}
41 FilterPrimitive * FilterMerge::create() {
42 return new FilterMerge();
43 }
45 FilterMerge::~FilterMerge()
46 {}
48 int FilterMerge::render(FilterSlot &slot, Matrix const &trans) {
49 NRPixBlock *in[_input_image.size()];
50 NRPixBlock *original_in[_input_image.size()];
52 for (unsigned int i = 0 ; i < _input_image.size() ; i++) {
53 in[i] = slot.get(_input_image[i]);
54 original_in[i] = in[i];
55 }
57 NRPixBlock *out;
59 // Bail out if either one of source images is missing
60 for (unsigned int i = 0 ; i < _input_image.size() ; i++) {
61 if (!in[i]) {
62 g_warning("Missing source image for feMerge (number=%d slot=%d)", i, _input_image[i]);
63 return 1;
64 }
65 }
67 out = new NRPixBlock;
68 NRRectL out_area = in[0]->area;
69 for (unsigned int i = 1 ; i < _input_image.size() ; i++) {
70 nr_rect_l_union(&out_area, &out_area, &in[i]->area);
71 }
72 nr_pixblock_setup_fast(out, NR_PIXBLOCK_MODE_R8G8B8A8P,
73 out_area.x0, out_area.y0, out_area.x1, out_area.y1,
74 true);
76 // Merge is defined for premultiplied RGBA values, thus convert them to
77 // that format before blending
78 for (unsigned int i = 0 ; i < _input_image.size() ; i++) {
79 if (in[i]->mode != NR_PIXBLOCK_MODE_R8G8B8A8P) {
80 in[i] = new NRPixBlock;
81 nr_pixblock_setup_fast(in[i], NR_PIXBLOCK_MODE_R8G8B8A8P,
82 original_in[i]->area.x0,
83 original_in[i]->area.y0,
84 original_in[i]->area.x1,
85 original_in[i]->area.y1,
86 false);
87 nr_blit_pixblock_pixblock(in[i], original_in[i]);
88 }
89 }
91 /* pixops_mix is defined in display/nr-filter-pixops.h
92 * It mixes the two input images with the function given as template
93 * and places the result in output image.
94 */
95 for (unsigned int i = 0 ; i < _input_image.size() ; i++) {
96 pixops_mix<composite_over>(*out, *in[i], *out);
97 }
99 for (unsigned int i = 0 ; i < _input_image.size() ; i++) {
100 if (in[i] != original_in[i]) {
101 nr_pixblock_release(in[i]);
102 delete in[i];
103 }
104 }
106 out->empty = FALSE;
107 slot.set(_output, out);
109 return 0;
110 }
112 void FilterMerge::set_input(int slot) {
113 _input_image[0] = slot;
114 }
116 void FilterMerge::set_input(int input, int slot) {
117 if (input < 0) return;
119 if (_input_image.size() > input) {
120 _input_image[input] = slot;
121 } else {
122 for (unsigned int i = _input_image.size() ; i < input ; i++) {
123 _input_image.push_back(NR_FILTER_SLOT_NOT_SET);
124 }
125 _input_image.push_back(slot);
126 }
127 }
129 } /* namespace NR */
131 /*
132 Local Variables:
133 mode:c++
134 c-file-style:"stroustrup"
135 c-file-offsets:((innamespace . 0)(inline-open . 0)(case-label . +))
136 indent-tabs-mode:nil
137 fill-column:99
138 End:
139 */
140 // vim: filetype=cpp:expandtab:shiftwidth=4:tabstop=8:softtabstop=4:encoding=utf-8:textwidth=99 :