Added support for feMerge filter priitive

(bzr r3308)

4 files changed, 195 insertions, 1 deletions

diff --git a/src/display/Makefile_insert b/src/display/Makefile_insert
index 624733a42..1713dc751 100644
--- a/src/display/Makefile_insert
+++ b/src/display/Makefile_insert
@@ -83,6 +83,8 @@ display_libspdisplay_a_SOURCES = \
 	display/nr-filter-getalpha.h	\
     display/nr-filter-image.cpp	\
     display/nr-filter-image.h	\
+	display/nr-filter-merge.cpp	\
+	display/nr-filter-merge.h	\
 	display/nr-filter-offset.cpp	\
 	display/nr-filter-offset.h	\
 	display/nr-filter-primitive.cpp \
diff --git a/src/display/nr-filter-merge.cpp b/src/display/nr-filter-merge.cpp
new file mode 100644
index 000000000..8650fee8b
--- /dev/null
+++ b/src/display/nr-filter-merge.cpp
@@ -0,0 +1,140 @@
+/*
+ * feMerge filter effect renderer
+ *
+ * Authors:
+ *   Niko Kiirala <niko@kiirala.com>
+ *
+ * Copyright (C) 2007 authors
+ *
+ * Released under GNU GPL, read the file 'COPYING' for more information
+ */
+
+#include <cmath>
+#include <vector>
+
+#include "isnan.h"
+#include "sp-femerge.h"
+#include "display/nr-filter-merge.h"
+#include "display/nr-filter-pixops.h"
+#include "display/nr-filter-slot.h"
+#include "display/nr-filter-utils.h"
+#include "libnr/nr-blit.h"
+#include "libnr/nr-pixblock.h"
+#include "libnr/nr-pixops.h"
+#include "libnr/nr-matrix.h"
+
+inline void
+composite_over(unsigned char *r, unsigned char const *a, unsigned char const *b)
+{
+    r[0] = a[0] + NR_NORMALIZE_21(b[0] * (255 - a[3]));
+    r[1] = a[1] + NR_NORMALIZE_21(b[1] * (255 - a[3]));
+    r[2] = a[2] + NR_NORMALIZE_21(b[2] * (255 - a[3]));
+    r[3] = a[3] + NR_NORMALIZE_21(b[3] * (255 - a[3]));
+}
+
+namespace NR {
+
+FilterMerge::FilterMerge() :
+    _input_image(1, NR_FILTER_SLOT_NOT_SET)
+{}
+
+FilterPrimitive * FilterMerge::create() {
+    return new FilterMerge();
+}
+
+FilterMerge::~FilterMerge()
+{}
+
+int FilterMerge::render(FilterSlot &slot, Matrix const &trans) {
+    NRPixBlock *in[_input_image.size()];
+    NRPixBlock *original_in[_input_image.size()];
+
+    for (unsigned int i = 0 ; i < _input_image.size() ; i++) {
+        in[i] = slot.get(_input_image[i]);
+        original_in[i] = in[i];
+    }
+
+    NRPixBlock *out;
+
+    // Bail out if either one of source images is missing
+    for (unsigned int i = 0 ; i < _input_image.size() ; i++) {
+        if (!in[i]) {
+            g_warning("Missing source image for feMerge (number=%d slot=%d)", i, _input_image[i]);
+            return 1;
+        }
+    }
+
+    out = new NRPixBlock;
+    NRRectL out_area = in[0]->area;
+    for (unsigned int i = 1 ; i < _input_image.size() ; i++) {
+        nr_rect_l_union(&out_area, &out_area, &in[i]->area);
+    }
+    nr_pixblock_setup_fast(out, NR_PIXBLOCK_MODE_R8G8B8A8P,
+                           out_area.x0, out_area.y0, out_area.x1, out_area.y1,
+                           true);
+
+    // Merge is defined for premultiplied RGBA values, thus convert them to
+    // that format before blending
+    for (unsigned int i = 0 ; i < _input_image.size() ; i++) {
+        if (in[i]->mode != NR_PIXBLOCK_MODE_R8G8B8A8P) {
+            in[i] = new NRPixBlock;
+            nr_pixblock_setup_fast(in[i], NR_PIXBLOCK_MODE_R8G8B8A8P,
+                                   original_in[i]->area.x0,
+                                   original_in[i]->area.y0,
+                                   original_in[i]->area.x1,
+                                   original_in[i]->area.y1,
+                                   false);
+            nr_blit_pixblock_pixblock(in[i], original_in[i]);
+        }
+    }
+
+    /* pixops_mix is defined in display/nr-filter-pixops.h
+     * It mixes the two input images with the function given as template
+     * and places the result in output image.
+     */
+    for (unsigned int i = 0 ; i < _input_image.size() ; i++) {
+        pixops_mix<composite_over>(*out, *in[i], *out);
+    }
+
+    for (unsigned int i = 0 ; i < _input_image.size() ; i++) {
+        if (in[i] != original_in[i]) {
+            nr_pixblock_release(in[i]);
+            delete in[i];
+        }
+    }
+
+    out->empty = FALSE;
+    slot.set(_output, out);
+
+    return 0;
+}
+
+void FilterMerge::set_input(int slot) {
+    _input_image[0] = slot;
+}
+
+void FilterMerge::set_input(int input, int slot) {
+    if (input < 0) return;
+
+    if (_input_image.size() > input) {
+        _input_image[input] = slot;
+    } else {
+        for (unsigned int i = _input_image.size() ; i < input ; i++) {
+            _input_image.push_back(NR_FILTER_SLOT_NOT_SET);
+        }
+        _input_image.push_back(slot);
+    }
+}
+
+} /* namespace NR */
+
+/*
+  Local Variables:
+  mode:c++
+  c-file-style:"stroustrup"
+  c-file-offsets:((innamespace . 0)(inline-open . 0)(case-label . +))
+  indent-tabs-mode:nil
+  fill-column:99
+  End:
+*/
+// vim: filetype=cpp:expandtab:shiftwidth=4:tabstop=8:softtabstop=4:encoding=utf-8:textwidth=99 :
diff --git a/src/display/nr-filter-merge.h b/src/display/nr-filter-merge.h
new file mode 100644
index 000000000..a88819c50
--- /dev/null
+++ b/src/display/nr-filter-merge.h
@@ -0,0 +1,51 @@
+#ifndef __NR_FILTER_MERGE_H__
+#define __NR_FILTER_MERGE_H__
+
+/*
+ * feMerge filter effect renderer
+ *
+ * Authors:
+ *   Niko Kiirala <niko@kiirala.com>
+ *
+ * Copyright (C) 2007 authors
+ *
+ * Released under GNU GPL, read the file 'COPYING' for more information
+ */
+
+#include <vector>
+
+#include "sp-femerge.h"
+#include "display/nr-filter-primitive.h"
+#include "display/nr-filter-slot.h"
+#include "libnr/nr-matrix.h"
+
+namespace NR {
+
+class FilterMerge : public FilterPrimitive {
+public:
+    FilterMerge();
+    static FilterPrimitive *create();
+    virtual ~FilterMerge();
+
+    virtual int render(FilterSlot &slot, Matrix const &trans);
+
+    virtual void set_input(int input);
+    virtual void set_input(int input, int slot);
+
+private:
+    std::vector<int> _input_image;
+};
+
+} /* namespace NR */
+
+#endif /* __NR_FILTER_MERGE_H__ */
+/*
+  Local Variables:
+  mode:c++
+  c-file-style:"stroustrup"
+  c-file-offsets:((innamespace . 0)(inline-open . 0)(case-label . +))
+  indent-tabs-mode:nil
+  fill-column:99
+  End:
+*/
+// vim: filetype=cpp:expandtab:shiftwidth=4:tabstop=8:softtabstop=4:encoding=utf-8:textwidth=99 :
diff --git a/src/display/nr-filter.cpp b/src/display/nr-filter.cpp
index f09573eb4..95867363b 100644
--- a/src/display/nr-filter.cpp
+++ b/src/display/nr-filter.cpp
@@ -28,6 +28,7 @@
 #include "display/nr-filter-displacement-map.h"
 #include "display/nr-filter-gaussian.h"
 #include "display/nr-filter-image.h"
+#include "display/nr-filter-merge.h"
 #include "display/nr-filter-offset.h"
 #include "display/nr-filter-specularlighting.h"
 #include "display/nr-filter-turbulence.h"
@@ -326,7 +327,7 @@ void Filter::_create_constructor_table()
     _constructor[NR_FILTER_FLOOD] = NULL;
     _constructor[NR_FILTER_GAUSSIANBLUR] = &FilterGaussian::create;
     _constructor[NR_FILTER_IMAGE] = &FilterImage::create;
-    _constructor[NR_FILTER_MERGE] = NULL;
+    _constructor[NR_FILTER_MERGE] = &FilterMerge::create;
     _constructor[NR_FILTER_MORPHOLOGY] = NULL;
     _constructor[NR_FILTER_OFFSET] = &FilterOffset::create;
     _constructor[NR_FILTER_SPECULARLIGHTING] = &FilterSpecularLighting::create;