[gnome-photos/wip/rishi/multiply] Add a filter for the SVG blend operation multiply

[Debarshi Ray <debarshir src gnome org>]

commit b47d369569ccd0286c2f35c7c527d6932f36cd83
Author: Debarshi Ray <debarshir gnome org>
Date:   Wed Jun 21 17:19:56 2017 +0200

    Add a filter for the SVG blend operation multiply

 src/Makefile.am                     |    4 +
 src/photos-operation-svg-multiply.c |  287 +++++++++++++++++++++++++++++++++++
 src/photos-operation-svg-multiply.h |   39 +++++
 3 files changed, 330 insertions(+), 0 deletions(-)
---
diff --git a/src/Makefile.am b/src/Makefile.am
index 62a6940..b0649b6 100644
--- a/src/Makefile.am
+++ b/src/Makefile.am
@@ -166,6 +166,8 @@ gnome_photos_SOURCES = \
        photos-operation-png-guess-sizes.h \
        photos-operation-saturation.c \
        photos-operation-saturation.h \
+       photos-operation-svg-multiply.c \
+       photos-operation-svg-multiply.h \
        photos-organize-collection-dialog.c \
        photos-organize-collection-dialog.h \
        photos-organize-collection-model.c \
@@ -332,6 +334,8 @@ gnome_photos_thumbnailer_SOURCES = \
        photos-operation-png-guess-sizes.h \
        photos-operation-saturation.c \
        photos-operation-saturation.h \
+       photos-operation-svg-multiply.c \
+       photos-operation-svg-multiply.h \
        photos-pipeline.c \
        photos-pipeline.h \
        photos-pixbuf.c \
diff --git a/src/photos-operation-svg-multiply.c b/src/photos-operation-svg-multiply.c
new file mode 100644
index 0000000..79da55c
--- /dev/null
+++ b/src/photos-operation-svg-multiply.c
@@ -0,0 +1,287 @@
+/*
+ * Photos - access, organize and share your photos on GNOME
+ * Copyright © 2017 Red Hat, Inc.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
+ * 02110-1301, USA.
+ */
+
+
+#include "config.h"
+
+#include <babl/babl.h>
+#include <gegl.h>
+
+#include "photos-operation-svg-multiply.h"
+
+
+typedef void (*PhotosOperationProcessFunc) (GeglOperation *,
+                                            void *,
+                                            void *,
+                                            void *,
+                                            glong,
+                                            const GeglRectangle *,
+                                            gint);
+
+struct _PhotosOperationSvgMultiply
+{
+  GeglOperationPointComposer parent_instance;
+  PhotosOperationProcessFunc process;
+  gboolean srgb;
+};
+
+enum
+{
+  PROP_0,
+  PROP_SRGB
+};
+
+
+G_DEFINE_TYPE (PhotosOperationSvgMultiply, photos_operation_svg_multiply, 
GEGL_TYPE_OPERATION_POINT_COMPOSER);
+
+
+static void
+photos_operation_svg_multiply_process_lab (GeglOperation *operation,
+                                           void *in_buf,
+                                           void *out_buf,
+                                           glong n_pixels,
+                                           const GeglRectangle *roi,
+                                           gint level)
+{
+  PhotosOperationSvgMultiply *self = PHOTOS_OPERATION_SVG_MULTIPLY (operation);
+  gfloat *in = in_buf;
+  gfloat *out = out_buf;
+  glong i;
+
+  for (i = 0; i < n_pixels; i++)
+    {
+      out[0] = in[0];
+      out[1] = in[1] * self->scale;
+      out[2] = in[2] * self->scale;
+
+      in += 3;
+      out += 3;
+    }
+}
+
+
+static void
+photos_operation_svg_multiply_process_lab_alpha (GeglOperation *operation,
+                                                 void *in_buf,
+                                                 void *out_buf,
+                                                 glong n_pixels,
+                                                 const GeglRectangle *roi,
+                                                 gint level)
+{
+  PhotosOperationSvgMultiply *self = PHOTOS_OPERATION_SVG_MULTIPLY (operation);
+  gfloat *in = in_buf;
+  gfloat *out = out_buf;
+  glong i;
+
+  for (i = 0; i < n_pixels; i++)
+    {
+      out[0] = in[0];
+      out[1] = in[1] * self->scale;
+      out[2] = in[2] * self->scale;
+      out[3] = in[3];
+
+      in += 4;
+      out += 4;
+    }
+}
+
+
+static void
+photos_operation_svg_multiply_process_lch (GeglOperation *operation,
+                                         void *in_buf,
+                                         void *out_buf,
+                                         glong n_pixels,
+                                         const GeglRectangle *roi,
+                                         gint level)
+{
+  PhotosOperationSvgMultiply *self = PHOTOS_OPERATION_SVG_MULTIPLY (operation);
+  gfloat *in = in_buf;
+  gfloat *out = out_buf;
+  glong i;
+
+  for (i = 0; i < n_pixels; i++)
+    {
+      out[0] = in[0];
+      out[1] = in[1] * self->scale;
+      out[2] = in[2];
+
+      in += 3;
+      out += 3;
+    }
+}
+
+
+static void
+photos_operation_svg_multiply_process_lch_alpha (GeglOperation *operation,
+                                               void *in_buf,
+                                               void *out_buf,
+                                               glong n_pixels,
+                                               const GeglRectangle *roi,
+                                               gint level)
+{
+  PhotosOperationSvgMultiply *self = PHOTOS_OPERATION_SVG_MULTIPLY (operation);
+  gfloat *in = in_buf;
+  gfloat *out = out_buf;
+  glong i;
+
+  for (i = 0; i < n_pixels; i++)
+    {
+      out[0] = in[0];
+      out[1] = in[1] * self->scale;
+      out[2] = in[2];
+      out[3] = in[3];
+
+      in += 4;
+      out += 4;
+    }
+}
+
+
+static void
+photos_operation_svg_multiply_prepare (GeglOperation *operation)
+{
+  PhotosOperationSvgMultiply *self = PHOTOS_OPERATION_SVG_MULTIPLY (operation);
+  const Babl *format;
+  const Babl *input_format;
+
+  input_format = gegl_operation_get_source_format (operation, "input");
+  if (input_format == NULL)
+    return;
+
+  if (babl_format_has_alpha (input_format))
+    {
+      model_lch = babl_model ("CIE LCH(ab) alpha");
+      if (model_input == model_lch)
+        {
+          format = babl_format ("CIE LCH(ab) alpha float");
+          self->process = photos_operation_svg_multiply_process_lch_alpha;
+        }
+      else
+        {
+          format = babl_format ("CIE Lab alpha float");
+          self->process = photos_operation_svg_multiply_process_lab_alpha;
+        }
+    }
+  else
+    {
+      model_lch = babl_model ("CIE LCH(ab)");
+      if (model_input == model_lch)
+        {
+          format = babl_format ("CIE LCH(ab) float");
+          self->process = photos_operation_svg_multiply_process_lch;
+        }
+      else
+        {
+          format = babl_format ("CIE Lab float");
+          self->process = photos_operation_svg_multiply_process_lab;
+        }
+    }
+
+  gegl_operation_set_format (operation, "input", format);
+  gegl_operation_set_format (operation, "output", format);
+}
+
+
+static gboolean
+photos_operation_svg_multiply_process (GeglOperation *operation,
+                                     void *in_buf,
+                                     void *out_buf,
+                                     glong n_pixels,
+                                     const GeglRectangle *roi,
+                                     gint level)
+{
+  PhotosOperationSvgMultiply *self = PHOTOS_OPERATION_SVG_MULTIPLY (operation);
+
+  self->process (operation, in_buf, out_buf, n_pixels, roi, level);
+  return TRUE;
+}
+
+
+static void
+photos_operation_svg_multiply_get_property (GObject *object, guint prop_id, GValue *value, GParamSpec *pspec)
+{
+  PhotosOperationSvgMultiply *self = PHOTOS_OPERATION_SVG_MULTIPLY (object);
+
+  switch (prop_id)
+    {
+    case PROP_SCALE:
+      g_value_set_double (value, (gdouble) self->scale);
+      break;
+
+    default:
+      G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
+      break;
+    }
+}
+
+
+static void
+photos_operation_svg_multiply_set_property (GObject *object, guint prop_id, const GValue *value, GParamSpec 
*pspec)
+{
+  PhotosOperationSvgMultiply *self = PHOTOS_OPERATION_SVG_MULTIPLY (object);
+
+  switch (prop_id)
+    {
+    case PROP_SCALE:
+      self->scale = (gfloat) g_value_get_double (value);
+      break;
+
+    default:
+      G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
+      break;
+    }
+}
+
+
+static void
+photos_operation_svg_multiply_init (PhotosOperationSvgMultiply *self)
+{
+}
+
+
+static void
+photos_operation_svg_multiply_class_init (PhotosOperationSvgMultiplyClass *class)
+{
+  GObjectClass *object_class = G_OBJECT_CLASS (class);
+  GeglOperationClass *operation_class = GEGL_OPERATION_CLASS (class);
+  GeglOperationPointFilterClass *point_filter_class = GEGL_OPERATION_POINT_FILTER_CLASS (class);
+
+  operation_class->opencl_support = FALSE;
+
+  object_class->get_property = photos_operation_svg_multiply_get_property;
+  object_class->set_property = photos_operation_svg_multiply_set_property;
+  operation_class->prepare = photos_operation_svg_multiply_prepare;
+  point_filter_class->process = photos_operation_svg_multiply_process;
+
+  g_object_class_install_property (object_class,
+                                   PROP_SRGB,
+                                   g_param_spec_boolean ("srgb",
+                                                         "sRGB",
+                                                         "Use sRGB gamma instead of linear",
+                                                         FALSE,
+                                                         G_PARAM_CONSTRUCT | G_PARAM_READWRITE));
+
+  gegl_operation_class_set_keys (operation_class,
+                                 "name", "photos:svg-multiply",
+                                 "title", "SVG Multiply",
+                                 "description", "SVG blend operation multiply",
+                                 "categories", "compositors:svgfilter",
+                                 NULL);
+}
diff --git a/src/photos-operation-svg-multiply.h b/src/photos-operation-svg-multiply.h
new file mode 100644
index 0000000..0aa0357
--- /dev/null
+++ b/src/photos-operation-svg-multiply.h
@@ -0,0 +1,39 @@
+/*
+ * Photos - access, organize and share your photos on GNOME
+ * Copyright © 2017 Red Hat, Inc.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
+ * 02110-1301, USA.
+ */
+
+#ifndef PHOTOS_OPERATION_SVG_MULTIPLY_H
+#define PHOTOS_OPERATION_SVG_MULTIPLY_H
+
+#include <gegl-plugin.h>
+
+#include "photos-gegl.h"
+
+G_BEGIN_DECLS
+
+#define PHOTOS_TYPE_OPERATION_SVG_MULTIPLY (photos_operation_svg_multiply_get_type ())
+G_DECLARE_FINAL_TYPE (PhotosOperationSvgMultiply,
+                      photos_operation_svg_multiply,
+                      PHOTOS,
+                      OPERATION_SVG_MULTIPLY,
+                      GeglOperationPointComposer);
+
+G_END_DECLS
+
+#endif /* PHOTOS_OPERATION_SVG_MULTIPLY_H */