geometrictransform: Adds a intermediary baseclass circlegeometrictransform

Adds an intermediary baseclass named gstcirclegeometrictransform
to keep common properties code for filters that operate on
a circular area.
diff --git a/gst/geometrictransform/gstcirclegeometrictransform.c b/gst/geometrictransform/gstcirclegeometrictransform.c
new file mode 100644
index 0000000..dfc10bc
--- /dev/null
+++ b/gst/geometrictransform/gstcirclegeometrictransform.c
@@ -0,0 +1,225 @@
+/*
+ * GStreamer
+ * Copyright (C) 2010 Thiago Santos <thiago.sousa.santos@collabora.co.uk>
+ * 
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+ * DEALINGS IN THE SOFTWARE.
+ *
+ * Alternatively, the contents of this file may be used under the
+ * GNU Lesser General Public License Version 2.1 (the "LGPL"), in
+ * which case the following provisions apply instead of the ones
+ * mentioned above:
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Library General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This library 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
+ * Library General Public License for more details.
+ *
+ * You should have received a copy of the GNU Library General Public
+ * License along with this library; if not, write to the
+ * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+ * Boston, MA 02111-1307, USA.
+ */
+
+/*
+ * Thanks to Jerry Huxtable <http://www.jhlabs.com> work on its java
+ * image editor and filters. The algorithms here were extracted from
+ * his code.
+ */
+
+
+#ifdef HAVE_CONFIG_H
+#  include <config.h>
+#endif
+
+#include <gst/gst.h>
+#include <math.h>
+
+#include "gstcirclegeometrictransform.h"
+
+GST_DEBUG_CATEGORY_STATIC (gst_circle_geometric_transform_debug);
+#define GST_CAT_DEFAULT gst_circle_geometric_transform_debug
+
+GstGeometricTransformClass *parent_class;
+
+enum
+{
+  PROP_0,
+  PROP_X_CENTER,
+  PROP_Y_CENTER,
+  PROP_RADIUS
+};
+
+#define DEFAULT_X_CENTER 0.5
+#define DEFAULT_Y_CENTER 0.5
+#define DEFAULT_RADIUS 100
+
+static void
+gst_circle_geometric_transform_set_property (GObject * object, guint prop_id,
+    const GValue * value, GParamSpec * pspec)
+{
+  GstCircleGeometricTransform *circle_geometric_transform;
+
+  circle_geometric_transform = GST_CIRCLE_GEOMETRIC_TRANSFORM_CAST (object);
+
+  switch (prop_id) {
+    case PROP_X_CENTER:
+      circle_geometric_transform->x_center = g_value_get_double (value);
+      break;
+    case PROP_Y_CENTER:
+      circle_geometric_transform->y_center = g_value_get_double (value);
+      break;
+    case PROP_RADIUS:
+      circle_geometric_transform->radius = g_value_get_double (value);
+      break;
+    default:
+      G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
+      break;
+  }
+}
+
+static void
+gst_circle_geometric_transform_get_property (GObject * object, guint prop_id,
+    GValue * value, GParamSpec * pspec)
+{
+  GstCircleGeometricTransform *circle_geometric_transform;
+
+  circle_geometric_transform = GST_CIRCLE_GEOMETRIC_TRANSFORM_CAST (object);
+
+  switch (prop_id) {
+    case PROP_X_CENTER:
+      g_value_set_double (value, circle_geometric_transform->x_center);
+      break;
+    case PROP_Y_CENTER:
+      g_value_set_double (value, circle_geometric_transform->y_center);
+      break;
+    case PROP_RADIUS:
+      g_value_set_double (value, circle_geometric_transform->radius);
+      break;
+    default:
+      G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
+      break;
+  }
+}
+
+/* Clean up */
+static void
+gst_circle_geometric_transform_finalize (GObject * obj)
+{
+  G_OBJECT_CLASS (parent_class)->finalize (obj);
+}
+
+/* GObject vmethod implementations */
+
+static gboolean
+circle_geometric_transform_precalc (GstGeometricTransform * gt)
+{
+  GstCircleGeometricTransform *cgt = GST_CIRCLE_GEOMETRIC_TRANSFORM_CAST (gt);
+
+  cgt->precalc_x_center = cgt->x_center * gt->width;
+  cgt->precalc_y_center = cgt->y_center * gt->height;
+  cgt->precalc_radius2 = cgt->radius * cgt->radius;
+
+  return TRUE;
+}
+
+static void
+gst_circle_geometric_transform_class_init (GstCircleGeometricTransformClass *
+    klass)
+{
+  GObjectClass *gobject_class;
+  GstGeometricTransformClass *gstgt_class;
+
+  gobject_class = (GObjectClass *) klass;
+  gstgt_class = (GstGeometricTransformClass *) klass;
+
+  parent_class = g_type_class_peek_parent (klass);
+
+  gobject_class->finalize =
+      GST_DEBUG_FUNCPTR (gst_circle_geometric_transform_finalize);
+  gobject_class->set_property =
+      GST_DEBUG_FUNCPTR (gst_circle_geometric_transform_set_property);
+  gobject_class->get_property =
+      GST_DEBUG_FUNCPTR (gst_circle_geometric_transform_get_property);
+
+
+  /* FIXME I don't like the idea of x-center and y-center being in % and
+   * radius and intensity in absolute values, I think no one likes it, but
+   * I can't see a way to have nice default values without % */
+  g_object_class_install_property (gobject_class, PROP_X_CENTER,
+      g_param_spec_double ("x-center", "x center",
+          "X axis center of the circle_geometric_transform effect",
+          0.0, 1.0, DEFAULT_X_CENTER,
+          G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
+  g_object_class_install_property (gobject_class, PROP_Y_CENTER,
+      g_param_spec_double ("y-center", "y center",
+          "Y axis center of the circle_geometric_transform effect",
+          0.0, 1.0, DEFAULT_Y_CENTER,
+          G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
+  g_object_class_install_property (gobject_class, PROP_RADIUS,
+      g_param_spec_double ("radius", "radius",
+          "radius of the circle_geometric_transform effect", 0.0, G_MAXDOUBLE,
+          DEFAULT_RADIUS, G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
+
+  gstgt_class->prepare_func = circle_geometric_transform_precalc;
+}
+
+static void
+gst_circle_geometric_transform_init (GstCircleGeometricTransform * filter,
+    GstCircleGeometricTransformClass * gclass)
+{
+  filter->x_center = DEFAULT_X_CENTER;
+  filter->y_center = DEFAULT_Y_CENTER;
+  filter->radius = DEFAULT_RADIUS;
+}
+
+GType
+gst_circle_geometric_transform_get_type (void)
+{
+  static GType circle_geometric_transform_type = 0;
+
+  if (!circle_geometric_transform_type) {
+    static const GTypeInfo circle_geometric_transform_info = {
+      sizeof (GstCircleGeometricTransformClass),
+      NULL,
+      NULL,
+      (GClassInitFunc) gst_circle_geometric_transform_class_init,
+      NULL,
+      NULL,
+      sizeof (GstCircleGeometricTransform),
+      0,
+      (GInstanceInitFunc) gst_circle_geometric_transform_init,
+    };
+
+    circle_geometric_transform_type =
+        g_type_register_static (GST_TYPE_GEOMETRIC_TRANSFORM,
+        "GstCircleGeometricTransform", &circle_geometric_transform_info,
+        G_TYPE_FLAG_ABSTRACT);
+
+    GST_DEBUG_CATEGORY_INIT (gst_circle_geometric_transform_debug,
+        "circlegeometrictransform", 0,
+        "Base class for geometric transform elements that operate "
+        "on a circular area");
+  }
+  return circle_geometric_transform_type;
+}