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-rw-r--r--app/core/gimpcurve.c1289
1 files changed, 1289 insertions, 0 deletions
diff --git a/app/core/gimpcurve.c b/app/core/gimpcurve.c
new file mode 100644
index 0000000..bde20b2
--- /dev/null
+++ b/app/core/gimpcurve.c
@@ -0,0 +1,1289 @@
+/* GIMP - The GNU Image Manipulation Program
+ * Copyright (C) 1995 Spencer Kimball and Peter Mattis
+ *
+ * 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 3 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, see <https://www.gnu.org/licenses/>.
+ */
+
+#include "config.h"
+
+#include <stdlib.h>
+#include <string.h> /* memcmp */
+
+#include <gdk-pixbuf/gdk-pixbuf.h>
+#include <gegl.h>
+
+#include "libgimpbase/gimpbase.h"
+#include "libgimpmath/gimpmath.h"
+#include "libgimpconfig/gimpconfig.h"
+
+#include "core-types.h"
+
+#include "gimpcurve.h"
+#include "gimpcurve-load.h"
+#include "gimpcurve-save.h"
+#include "gimpparamspecs.h"
+
+#include "gimp-intl.h"
+
+
+#define EPSILON 1e-6
+
+
+enum
+{
+ PROP_0,
+ PROP_CURVE_TYPE,
+ PROP_N_POINTS,
+ PROP_POINTS,
+ PROP_POINT_TYPES,
+ PROP_N_SAMPLES,
+ PROP_SAMPLES
+};
+
+
+/* local function prototypes */
+
+static void gimp_curve_config_iface_init (GimpConfigInterface *iface);
+
+static void gimp_curve_finalize (GObject *object);
+static void gimp_curve_set_property (GObject *object,
+ guint property_id,
+ const GValue *value,
+ GParamSpec *pspec);
+static void gimp_curve_get_property (GObject *object,
+ guint property_id,
+ GValue *value,
+ GParamSpec *pspec);
+
+static gint64 gimp_curve_get_memsize (GimpObject *object,
+ gint64 *gui_size);
+
+static void gimp_curve_get_preview_size (GimpViewable *viewable,
+ gint size,
+ gboolean popup,
+ gboolean dot_for_dot,
+ gint *width,
+ gint *height);
+static gboolean gimp_curve_get_popup_size (GimpViewable *viewable,
+ gint width,
+ gint height,
+ gboolean dot_for_dot,
+ gint *popup_width,
+ gint *popup_height);
+static GimpTempBuf * gimp_curve_get_new_preview (GimpViewable *viewable,
+ GimpContext *context,
+ gint width,
+ gint height);
+static gchar * gimp_curve_get_description (GimpViewable *viewable,
+ gchar **tooltip);
+
+static void gimp_curve_dirty (GimpData *data);
+static const gchar * gimp_curve_get_extension (GimpData *data);
+static void gimp_curve_data_copy (GimpData *data,
+ GimpData *src_data);
+
+static gboolean gimp_curve_serialize (GimpConfig *config,
+ GimpConfigWriter *writer,
+ gpointer data);
+static gboolean gimp_curve_deserialize (GimpConfig *config,
+ GScanner *scanner,
+ gint nest_level,
+ gpointer data);
+static gboolean gimp_curve_equal (GimpConfig *a,
+ GimpConfig *b);
+static void _gimp_curve_reset (GimpConfig *config);
+static gboolean gimp_curve_config_copy (GimpConfig *src,
+ GimpConfig *dest,
+ GParamFlags flags);
+
+static void gimp_curve_calculate (GimpCurve *curve);
+static void gimp_curve_plot (GimpCurve *curve,
+ gint p1,
+ gint p2,
+ gint p3,
+ gint p4);
+
+
+G_DEFINE_TYPE_WITH_CODE (GimpCurve, gimp_curve, GIMP_TYPE_DATA,
+ G_IMPLEMENT_INTERFACE (GIMP_TYPE_CONFIG,
+ gimp_curve_config_iface_init))
+
+#define parent_class gimp_curve_parent_class
+
+
+static void
+gimp_curve_class_init (GimpCurveClass *klass)
+{
+ GObjectClass *object_class = G_OBJECT_CLASS (klass);
+ GimpObjectClass *gimp_object_class = GIMP_OBJECT_CLASS (klass);
+ GimpViewableClass *viewable_class = GIMP_VIEWABLE_CLASS (klass);
+ GimpDataClass *data_class = GIMP_DATA_CLASS (klass);
+ GParamSpec *array_spec;
+
+ object_class->finalize = gimp_curve_finalize;
+ object_class->set_property = gimp_curve_set_property;
+ object_class->get_property = gimp_curve_get_property;
+
+ gimp_object_class->get_memsize = gimp_curve_get_memsize;
+
+ viewable_class->default_icon_name = "FIXME icon name";
+ viewable_class->get_preview_size = gimp_curve_get_preview_size;
+ viewable_class->get_popup_size = gimp_curve_get_popup_size;
+ viewable_class->get_new_preview = gimp_curve_get_new_preview;
+ viewable_class->get_description = gimp_curve_get_description;
+
+ data_class->dirty = gimp_curve_dirty;
+ data_class->save = gimp_curve_save;
+ data_class->get_extension = gimp_curve_get_extension;
+ data_class->copy = gimp_curve_data_copy;
+
+ GIMP_CONFIG_PROP_ENUM (object_class, PROP_CURVE_TYPE,
+ "curve-type",
+ "Curve Type",
+ "The curve type",
+ GIMP_TYPE_CURVE_TYPE,
+ GIMP_CURVE_SMOOTH, 0);
+
+ GIMP_CONFIG_PROP_INT (object_class, PROP_N_POINTS,
+ "n-points",
+ "Number of Points",
+ "The number of points",
+ 0, G_MAXINT, 0,
+ /* for backward compatibility */
+ GIMP_CONFIG_PARAM_IGNORE);
+
+ array_spec = g_param_spec_double ("point", NULL, NULL,
+ -1.0, 1.0, 0.0, GIMP_PARAM_READWRITE);
+ g_object_class_install_property (object_class, PROP_POINTS,
+ gimp_param_spec_value_array ("points",
+ NULL, NULL,
+ array_spec,
+ GIMP_PARAM_STATIC_STRINGS |
+ GIMP_CONFIG_PARAM_FLAGS));
+
+ array_spec = g_param_spec_enum ("point-type", NULL, NULL,
+ GIMP_TYPE_CURVE_POINT_TYPE,
+ GIMP_CURVE_POINT_SMOOTH,
+ GIMP_PARAM_READWRITE);
+ g_object_class_install_property (object_class, PROP_POINT_TYPES,
+ gimp_param_spec_value_array ("point-types",
+ NULL, NULL,
+ array_spec,
+ GIMP_PARAM_STATIC_STRINGS |
+ GIMP_CONFIG_PARAM_FLAGS));
+
+ GIMP_CONFIG_PROP_INT (object_class, PROP_N_SAMPLES,
+ "n-samples",
+ "Number of Samples",
+ "The number of samples",
+ 256, 256, 256, 0);
+
+ array_spec = g_param_spec_double ("sample", NULL, NULL,
+ 0.0, 1.0, 0.0, GIMP_PARAM_READWRITE);
+ g_object_class_install_property (object_class, PROP_SAMPLES,
+ gimp_param_spec_value_array ("samples",
+ NULL, NULL,
+ array_spec,
+ GIMP_PARAM_STATIC_STRINGS |
+ GIMP_CONFIG_PARAM_FLAGS));
+}
+
+static void
+gimp_curve_config_iface_init (GimpConfigInterface *iface)
+{
+ iface->serialize = gimp_curve_serialize;
+ iface->deserialize = gimp_curve_deserialize;
+ iface->equal = gimp_curve_equal;
+ iface->reset = _gimp_curve_reset;
+ iface->copy = gimp_curve_config_copy;
+}
+
+static void
+gimp_curve_init (GimpCurve *curve)
+{
+ curve->n_points = 0;
+ curve->points = NULL;
+ curve->n_samples = 0;
+ curve->samples = NULL;
+ curve->identity = FALSE;
+}
+
+static void
+gimp_curve_finalize (GObject *object)
+{
+ GimpCurve *curve = GIMP_CURVE (object);
+
+ g_clear_pointer (&curve->points, g_free);
+ curve->n_points = 0;
+
+ g_clear_pointer (&curve->samples, g_free);
+ curve->n_samples = 0;
+
+ G_OBJECT_CLASS (parent_class)->finalize (object);
+}
+
+static void
+gimp_curve_set_property (GObject *object,
+ guint property_id,
+ const GValue *value,
+ GParamSpec *pspec)
+{
+ GimpCurve *curve = GIMP_CURVE (object);
+
+ switch (property_id)
+ {
+ case PROP_CURVE_TYPE:
+ gimp_curve_set_curve_type (curve, g_value_get_enum (value));
+ break;
+
+ case PROP_N_POINTS:
+ /* ignored */
+ break;
+
+ case PROP_POINTS:
+ {
+ GimpValueArray *array = g_value_get_boxed (value);
+ GimpCurvePoint *points;
+ gint length;
+ gint n_points;
+ gint i;
+
+ if (! array)
+ {
+ gimp_curve_clear_points (curve);
+
+ break;
+ }
+
+ length = gimp_value_array_length (array) / 2;
+
+ n_points = 0;
+ points = g_new0 (GimpCurvePoint, length);
+
+ for (i = 0; i < length; i++)
+ {
+ GValue *x = gimp_value_array_index (array, i * 2);
+ GValue *y = gimp_value_array_index (array, i * 2 + 1);
+
+ /* for backward compatibility */
+ if (g_value_get_double (x) < 0.0)
+ continue;
+
+ points[n_points].x = CLAMP (g_value_get_double (x), 0.0, 1.0);
+ points[n_points].y = CLAMP (g_value_get_double (y), 0.0, 1.0);
+
+ if (n_points > 0)
+ {
+ points[n_points].x = MAX (points[n_points].x,
+ points[n_points - 1].x);
+ }
+
+ if (n_points < curve->n_points)
+ points[n_points].type = curve->points[n_points].type;
+ else
+ points[n_points].type = GIMP_CURVE_POINT_SMOOTH;
+
+ n_points++;
+ }
+
+ g_free (curve->points);
+
+ curve->n_points = n_points;
+ curve->points = points;
+
+ g_object_notify (object, "n-points");
+ g_object_notify (object, "point-types");
+ }
+ break;
+
+ case PROP_POINT_TYPES:
+ {
+ GimpValueArray *array = g_value_get_boxed (value);
+ GimpCurvePoint *points;
+ gint length;
+ gdouble x = 0.0;
+ gdouble y = 0.0;
+ gint i;
+
+ if (! array)
+ {
+ gimp_curve_clear_points (curve);
+
+ break;
+ }
+
+ length = gimp_value_array_length (array);
+
+ points = g_new0 (GimpCurvePoint, length);
+
+ for (i = 0; i < length; i++)
+ {
+ GValue *type = gimp_value_array_index (array, i);
+
+ points[i].type = g_value_get_enum (type);
+
+ if (i < curve->n_points)
+ {
+ x = curve->points[i].x;
+ y = curve->points[i].y;
+ }
+
+ points[i].x = x;
+ points[i].y = y;
+ }
+
+ g_free (curve->points);
+
+ curve->n_points = length;
+ curve->points = points;
+
+ g_object_notify (object, "n-points");
+ g_object_notify (object, "points");
+ }
+ break;
+
+ case PROP_N_SAMPLES:
+ gimp_curve_set_n_samples (curve, g_value_get_int (value));
+ break;
+
+ case PROP_SAMPLES:
+ {
+ GimpValueArray *array = g_value_get_boxed (value);
+ gint length;
+ gint i;
+
+ if (! array)
+ break;
+
+ length = gimp_value_array_length (array);
+
+ for (i = 0; i < curve->n_samples && i < length; i++)
+ {
+ GValue *v = gimp_value_array_index (array, i);
+
+ curve->samples[i] = CLAMP (g_value_get_double (v), 0.0, 1.0);
+ }
+ }
+ break;
+
+ default:
+ G_OBJECT_WARN_INVALID_PROPERTY_ID (object, property_id, pspec);
+ break;
+ }
+}
+
+static void
+gimp_curve_get_property (GObject *object,
+ guint property_id,
+ GValue *value,
+ GParamSpec *pspec)
+{
+ GimpCurve *curve = GIMP_CURVE (object);
+
+ switch (property_id)
+ {
+ case PROP_CURVE_TYPE:
+ g_value_set_enum (value, curve->curve_type);
+ break;
+
+ case PROP_N_POINTS:
+ g_value_set_int (value, curve->n_points);
+ break;
+
+ case PROP_POINTS:
+ {
+ GimpValueArray *array = gimp_value_array_new (curve->n_points * 2);
+ GValue v = G_VALUE_INIT;
+ gint i;
+
+ g_value_init (&v, G_TYPE_DOUBLE);
+
+ for (i = 0; i < curve->n_points; i++)
+ {
+ g_value_set_double (&v, curve->points[i].x);
+ gimp_value_array_append (array, &v);
+
+ g_value_set_double (&v, curve->points[i].y);
+ gimp_value_array_append (array, &v);
+ }
+
+ g_value_unset (&v);
+
+ g_value_take_boxed (value, array);
+ }
+ break;
+
+ case PROP_POINT_TYPES:
+ {
+ GimpValueArray *array = gimp_value_array_new (curve->n_points);
+ GValue v = G_VALUE_INIT;
+ gint i;
+
+ g_value_init (&v, GIMP_TYPE_CURVE_POINT_TYPE);
+
+ for (i = 0; i < curve->n_points; i++)
+ {
+ g_value_set_enum (&v, curve->points[i].type);
+ gimp_value_array_append (array, &v);
+ }
+
+ g_value_unset (&v);
+
+ g_value_take_boxed (value, array);
+ }
+ break;
+
+ case PROP_N_SAMPLES:
+ g_value_set_int (value, curve->n_samples);
+ break;
+
+ case PROP_SAMPLES:
+ {
+ GimpValueArray *array = gimp_value_array_new (curve->n_samples);
+ GValue v = G_VALUE_INIT;
+ gint i;
+
+ g_value_init (&v, G_TYPE_DOUBLE);
+
+ for (i = 0; i < curve->n_samples; i++)
+ {
+ g_value_set_double (&v, curve->samples[i]);
+ gimp_value_array_append (array, &v);
+ }
+
+ g_value_unset (&v);
+
+ g_value_take_boxed (value, array);
+ }
+ break;
+
+ default:
+ G_OBJECT_WARN_INVALID_PROPERTY_ID (object, property_id, pspec);
+ break;
+ }
+}
+
+static gint64
+gimp_curve_get_memsize (GimpObject *object,
+ gint64 *gui_size)
+{
+ GimpCurve *curve = GIMP_CURVE (object);
+ gint64 memsize = 0;
+
+ memsize += curve->n_points * sizeof (GimpCurvePoint);
+ memsize += curve->n_samples * sizeof (gdouble);
+
+ return memsize + GIMP_OBJECT_CLASS (parent_class)->get_memsize (object,
+ gui_size);
+}
+
+static void
+gimp_curve_get_preview_size (GimpViewable *viewable,
+ gint size,
+ gboolean popup,
+ gboolean dot_for_dot,
+ gint *width,
+ gint *height)
+{
+ *width = size;
+ *height = size;
+}
+
+static gboolean
+gimp_curve_get_popup_size (GimpViewable *viewable,
+ gint width,
+ gint height,
+ gboolean dot_for_dot,
+ gint *popup_width,
+ gint *popup_height)
+{
+ *popup_width = width * 2;
+ *popup_height = height * 2;
+
+ return TRUE;
+}
+
+static GimpTempBuf *
+gimp_curve_get_new_preview (GimpViewable *viewable,
+ GimpContext *context,
+ gint width,
+ gint height)
+{
+ return NULL;
+}
+
+static gchar *
+gimp_curve_get_description (GimpViewable *viewable,
+ gchar **tooltip)
+{
+ GimpCurve *curve = GIMP_CURVE (viewable);
+
+ return g_strdup_printf ("%s", gimp_object_get_name (curve));
+}
+
+static void
+gimp_curve_dirty (GimpData *data)
+{
+ GimpCurve *curve = GIMP_CURVE (data);
+
+ curve->identity = FALSE;
+
+ gimp_curve_calculate (curve);
+
+ GIMP_DATA_CLASS (parent_class)->dirty (data);
+}
+
+static const gchar *
+gimp_curve_get_extension (GimpData *data)
+{
+ return GIMP_CURVE_FILE_EXTENSION;
+}
+
+static void
+gimp_curve_data_copy (GimpData *data,
+ GimpData *src_data)
+{
+ gimp_data_freeze (data);
+
+ gimp_config_copy (GIMP_CONFIG (src_data),
+ GIMP_CONFIG (data), 0);
+
+ gimp_data_thaw (data);
+}
+
+static gboolean
+gimp_curve_serialize (GimpConfig *config,
+ GimpConfigWriter *writer,
+ gpointer data)
+{
+ return gimp_config_serialize_properties (config, writer);
+}
+
+static gboolean
+gimp_curve_deserialize (GimpConfig *config,
+ GScanner *scanner,
+ gint nest_level,
+ gpointer data)
+{
+ gboolean success;
+
+ success = gimp_config_deserialize_properties (config, scanner, nest_level);
+
+ GIMP_CURVE (config)->identity = FALSE;
+
+ return success;
+}
+
+static gboolean
+gimp_curve_equal (GimpConfig *a,
+ GimpConfig *b)
+{
+ GimpCurve *a_curve = GIMP_CURVE (a);
+ GimpCurve *b_curve = GIMP_CURVE (b);
+
+ if (a_curve->curve_type != b_curve->curve_type)
+ return FALSE;
+
+ if (a_curve->n_points != b_curve->n_points ||
+ memcmp (a_curve->points, b_curve->points,
+ sizeof (GimpCurvePoint) * a_curve->n_points))
+ {
+ return FALSE;
+ }
+
+ if (a_curve->n_samples != b_curve->n_samples ||
+ memcmp (a_curve->samples, b_curve->samples,
+ sizeof (gdouble) * a_curve->n_samples))
+ {
+ return FALSE;
+ }
+
+ return TRUE;
+}
+
+static void
+_gimp_curve_reset (GimpConfig *config)
+{
+ gimp_curve_reset (GIMP_CURVE (config), TRUE);
+}
+
+static gboolean
+gimp_curve_config_copy (GimpConfig *src,
+ GimpConfig *dest,
+ GParamFlags flags)
+{
+ GimpCurve *src_curve = GIMP_CURVE (src);
+ GimpCurve *dest_curve = GIMP_CURVE (dest);
+
+ /* make sure the curve type is copied *before* the points, so that we don't
+ * overwrite the copied points when changing the type
+ */
+ dest_curve->curve_type = src_curve->curve_type;
+
+ gimp_config_sync (G_OBJECT (src), G_OBJECT (dest), flags);
+
+ dest_curve->identity = src_curve->identity;
+
+ gimp_data_dirty (GIMP_DATA (dest));
+
+ return TRUE;
+}
+
+
+/* public functions */
+
+GimpData *
+gimp_curve_new (const gchar *name)
+{
+ g_return_val_if_fail (name != NULL, NULL);
+ g_return_val_if_fail (*name != '\0', NULL);
+
+ return g_object_new (GIMP_TYPE_CURVE,
+ "name", name,
+ NULL);
+}
+
+GimpData *
+gimp_curve_get_standard (void)
+{
+ static GimpData *standard_curve = NULL;
+
+ if (! standard_curve)
+ {
+ standard_curve = gimp_curve_new ("Standard");
+
+ gimp_data_clean (standard_curve);
+ gimp_data_make_internal (standard_curve,
+ "gimp-curve-standard");
+
+ g_object_ref (standard_curve);
+ }
+
+ return standard_curve;
+}
+
+void
+gimp_curve_reset (GimpCurve *curve,
+ gboolean reset_type)
+{
+ gint i;
+
+ g_return_if_fail (GIMP_IS_CURVE (curve));
+
+ g_object_freeze_notify (G_OBJECT (curve));
+
+ for (i = 0; i < curve->n_samples; i++)
+ curve->samples[i] = (gdouble) i / (gdouble) (curve->n_samples - 1);
+
+ g_object_notify (G_OBJECT (curve), "samples");
+
+ g_free (curve->points);
+
+ curve->n_points = 2;
+ curve->points = g_new0 (GimpCurvePoint, 2);
+
+ curve->points[0].x = 0.0;
+ curve->points[0].y = 0.0;
+ curve->points[0].type = GIMP_CURVE_POINT_SMOOTH;
+
+ curve->points[1].x = 1.0;
+ curve->points[1].y = 1.0;
+ curve->points[1].type = GIMP_CURVE_POINT_SMOOTH;
+
+ g_object_notify (G_OBJECT (curve), "n-points");
+ g_object_notify (G_OBJECT (curve), "points");
+ g_object_notify (G_OBJECT (curve), "point-types");
+
+ if (reset_type)
+ {
+ curve->curve_type = GIMP_CURVE_SMOOTH;
+ g_object_notify (G_OBJECT (curve), "curve-type");
+ }
+
+ curve->identity = TRUE;
+
+ g_object_thaw_notify (G_OBJECT (curve));
+
+ gimp_data_dirty (GIMP_DATA (curve));
+}
+
+void
+gimp_curve_set_curve_type (GimpCurve *curve,
+ GimpCurveType curve_type)
+{
+ g_return_if_fail (GIMP_IS_CURVE (curve));
+
+ if (curve->curve_type != curve_type)
+ {
+ gimp_data_freeze (GIMP_DATA (curve));
+
+ g_object_freeze_notify (G_OBJECT (curve));
+
+ curve->curve_type = curve_type;
+
+ if (curve_type == GIMP_CURVE_SMOOTH)
+ {
+ gint i;
+
+ g_free (curve->points);
+
+ /* pick some points from the curve and make them control
+ * points
+ */
+ curve->n_points = 9;
+ curve->points = g_new0 (GimpCurvePoint, 9);
+
+ for (i = 0; i < curve->n_points; i++)
+ {
+ gint sample = i * (curve->n_samples - 1) / (curve->n_points - 1);
+
+ curve->points[i].x = (gdouble) sample /
+ (gdouble) (curve->n_samples - 1);
+ curve->points[i].y = curve->samples[sample];
+ curve->points[i].type = GIMP_CURVE_POINT_SMOOTH;
+ }
+
+ g_object_notify (G_OBJECT (curve), "n-points");
+ g_object_notify (G_OBJECT (curve), "points");
+ g_object_notify (G_OBJECT (curve), "point-types");
+ }
+ else
+ {
+ gimp_curve_clear_points (curve);
+ }
+
+ g_object_notify (G_OBJECT (curve), "curve-type");
+
+ g_object_thaw_notify (G_OBJECT (curve));
+
+ gimp_data_thaw (GIMP_DATA (curve));
+ }
+}
+
+GimpCurveType
+gimp_curve_get_curve_type (GimpCurve *curve)
+{
+ g_return_val_if_fail (GIMP_IS_CURVE (curve), GIMP_CURVE_SMOOTH);
+
+ return curve->curve_type;
+}
+
+gint
+gimp_curve_get_n_points (GimpCurve *curve)
+{
+ g_return_val_if_fail (GIMP_IS_CURVE (curve), 0);
+
+ return curve->n_points;
+}
+
+void
+gimp_curve_set_n_samples (GimpCurve *curve,
+ gint n_samples)
+{
+ g_return_if_fail (GIMP_IS_CURVE (curve));
+ g_return_if_fail (n_samples >= 256);
+ g_return_if_fail (n_samples <= 4096);
+
+ if (n_samples != curve->n_samples)
+ {
+ gint i;
+
+ g_object_freeze_notify (G_OBJECT (curve));
+
+ curve->n_samples = n_samples;
+ g_object_notify (G_OBJECT (curve), "n-samples");
+
+ curve->samples = g_renew (gdouble, curve->samples, curve->n_samples);
+
+ for (i = 0; i < curve->n_samples; i++)
+ curve->samples[i] = (gdouble) i / (gdouble) (curve->n_samples - 1);
+
+ g_object_notify (G_OBJECT (curve), "samples");
+
+ if (curve->curve_type == GIMP_CURVE_FREE)
+ curve->identity = TRUE;
+
+ g_object_thaw_notify (G_OBJECT (curve));
+ }
+}
+
+gint
+gimp_curve_get_n_samples (GimpCurve *curve)
+{
+ g_return_val_if_fail (GIMP_IS_CURVE (curve), 0);
+
+ return curve->n_samples;
+}
+
+gint
+gimp_curve_get_point_at (GimpCurve *curve,
+ gdouble x)
+{
+ gint closest_point = -1;
+ gdouble distance = EPSILON;
+ gint i;
+
+ g_return_val_if_fail (GIMP_IS_CURVE (curve), -1);
+
+ for (i = 0; i < curve->n_points; i++)
+ {
+ gdouble point_distance;
+
+ point_distance = fabs (x - curve->points[i].x);
+
+ if (point_distance <= distance)
+ {
+ closest_point = i;
+ distance = point_distance;
+ }
+ }
+
+ return closest_point;
+}
+
+gint
+gimp_curve_get_closest_point (GimpCurve *curve,
+ gdouble x,
+ gdouble y,
+ gdouble max_distance)
+{
+ gint closest_point = -1;
+ gdouble distance2 = G_MAXDOUBLE;
+ gint i;
+
+ g_return_val_if_fail (GIMP_IS_CURVE (curve), -1);
+
+ if (max_distance >= 0.0)
+ distance2 = SQR (max_distance);
+
+ for (i = curve->n_points - 1; i >= 0; i--)
+ {
+ gdouble point_distance2;
+
+ point_distance2 = SQR (x - curve->points[i].x) +
+ SQR (y - curve->points[i].y);
+
+ if (point_distance2 <= distance2)
+ {
+ closest_point = i;
+ distance2 = point_distance2;
+ }
+ }
+
+ return closest_point;
+}
+
+gint
+gimp_curve_add_point (GimpCurve *curve,
+ gdouble x,
+ gdouble y)
+{
+ GimpCurvePoint *points;
+ gint point;
+
+ g_return_val_if_fail (GIMP_IS_CURVE (curve), -1);
+
+ if (curve->curve_type == GIMP_CURVE_FREE)
+ return -1;
+
+ x = CLAMP (x, 0.0, 1.0);
+ y = CLAMP (y, 0.0, 1.0);
+
+ for (point = 0; point < curve->n_points; point++)
+ {
+ if (curve->points[point].x > x)
+ break;
+ }
+
+ points = g_new0 (GimpCurvePoint, curve->n_points + 1);
+
+ memcpy (points, curve->points,
+ point * sizeof (GimpCurvePoint));
+ memcpy (points + point + 1, curve->points + point,
+ (curve->n_points - point) * sizeof (GimpCurvePoint));
+
+ points[point].x = x;
+ points[point].y = y;
+ points[point].type = GIMP_CURVE_POINT_SMOOTH;
+
+ g_free (curve->points);
+
+ curve->n_points++;
+ curve->points = points;
+
+ g_object_notify (G_OBJECT (curve), "n-points");
+ g_object_notify (G_OBJECT (curve), "points");
+ g_object_notify (G_OBJECT (curve), "point-types");
+
+ gimp_data_dirty (GIMP_DATA (curve));
+
+ return point;
+}
+
+void
+gimp_curve_delete_point (GimpCurve *curve,
+ gint point)
+{
+ GimpCurvePoint *points;
+
+ g_return_if_fail (GIMP_IS_CURVE (curve));
+ g_return_if_fail (point >= 0 && point < curve->n_points);
+
+ points = g_new0 (GimpCurvePoint, curve->n_points - 1);
+
+ memcpy (points, curve->points,
+ point * sizeof (GimpCurvePoint));
+ memcpy (points + point, curve->points + point + 1,
+ (curve->n_points - point - 1) * sizeof (GimpCurvePoint));
+
+ g_free (curve->points);
+
+ curve->n_points--;
+ curve->points = points;
+
+ g_object_notify (G_OBJECT (curve), "n-points");
+ g_object_notify (G_OBJECT (curve), "points");
+ g_object_notify (G_OBJECT (curve), "point-types");
+
+ gimp_data_dirty (GIMP_DATA (curve));
+}
+
+void
+gimp_curve_set_point (GimpCurve *curve,
+ gint point,
+ gdouble x,
+ gdouble y)
+{
+ g_return_if_fail (GIMP_IS_CURVE (curve));
+ g_return_if_fail (point >= 0 && point < curve->n_points);
+
+ curve->points[point].x = CLAMP (x, 0.0, 1.0);
+ curve->points[point].y = CLAMP (y, 0.0, 1.0);
+
+ if (point > 0)
+ curve->points[point].x = MAX (x, curve->points[point - 1].x);
+
+ if (point < curve->n_points - 1)
+ curve->points[point].x = MIN (x, curve->points[point + 1].x);
+
+ g_object_notify (G_OBJECT (curve), "points");
+
+ gimp_data_dirty (GIMP_DATA (curve));
+}
+
+void
+gimp_curve_move_point (GimpCurve *curve,
+ gint point,
+ gdouble y)
+{
+ g_return_if_fail (GIMP_IS_CURVE (curve));
+ g_return_if_fail (point >= 0 && point < curve->n_points);
+
+ curve->points[point].y = CLAMP (y, 0.0, 1.0);
+
+ g_object_notify (G_OBJECT (curve), "points");
+
+ gimp_data_dirty (GIMP_DATA (curve));
+}
+
+void
+gimp_curve_get_point (GimpCurve *curve,
+ gint point,
+ gdouble *x,
+ gdouble *y)
+{
+ g_return_if_fail (GIMP_IS_CURVE (curve));
+ g_return_if_fail (point >= 0 && point < curve->n_points);
+
+ if (x) *x = curve->points[point].x;
+ if (y) *y = curve->points[point].y;
+}
+
+void
+gimp_curve_set_point_type (GimpCurve *curve,
+ gint point,
+ GimpCurvePointType type)
+{
+ g_return_if_fail (GIMP_IS_CURVE (curve));
+ g_return_if_fail (point >= 0 && point < curve->n_points);
+
+ curve->points[point].type = type;
+
+ g_object_notify (G_OBJECT (curve), "point-types");
+
+ gimp_data_dirty (GIMP_DATA (curve));
+}
+
+GimpCurvePointType
+gimp_curve_get_point_type (GimpCurve *curve,
+ gint point)
+{
+ g_return_val_if_fail (GIMP_IS_CURVE (curve), GIMP_CURVE_POINT_SMOOTH);
+ g_return_val_if_fail (point >= 0 && point < curve->n_points, GIMP_CURVE_POINT_SMOOTH);
+
+ return curve->points[point].type;
+}
+
+void
+gimp_curve_clear_points (GimpCurve *curve)
+{
+ g_return_if_fail (GIMP_IS_CURVE (curve));
+
+ if (curve->points)
+ {
+ g_clear_pointer (&curve->points, g_free);
+ curve->n_points = 0;
+
+ g_object_notify (G_OBJECT (curve), "n-points");
+ g_object_notify (G_OBJECT (curve), "points");
+ g_object_notify (G_OBJECT (curve), "point-types");
+
+ gimp_data_dirty (GIMP_DATA (curve));
+ }
+}
+
+void
+gimp_curve_set_curve (GimpCurve *curve,
+ gdouble x,
+ gdouble y)
+{
+ g_return_if_fail (GIMP_IS_CURVE (curve));
+ g_return_if_fail (x >= 0 && x <= 1.0);
+ g_return_if_fail (y >= 0 && y <= 1.0);
+
+ if (curve->curve_type == GIMP_CURVE_SMOOTH)
+ return;
+
+ curve->samples[ROUND (x * (gdouble) (curve->n_samples - 1))] = y;
+
+ g_object_notify (G_OBJECT (curve), "samples");
+
+ gimp_data_dirty (GIMP_DATA (curve));
+}
+
+/**
+ * gimp_curve_is_identity:
+ * @curve: a #GimpCurve object
+ *
+ * If this function returns %TRUE, then the curve maps each value to
+ * itself. If it returns %FALSE, then this assumption can not be made.
+ *
+ * Return value: %TRUE if the curve is an identity mapping, %FALSE otherwise.
+ **/
+gboolean
+gimp_curve_is_identity (GimpCurve *curve)
+{
+ g_return_val_if_fail (GIMP_IS_CURVE (curve), FALSE);
+
+ return curve->identity;
+}
+
+void
+gimp_curve_get_uchar (GimpCurve *curve,
+ gint n_samples,
+ guchar *samples)
+{
+ gint i;
+
+ g_return_if_fail (GIMP_IS_CURVE (curve));
+ /* FIXME: support n_samples != curve->n_samples */
+ g_return_if_fail (n_samples == curve->n_samples);
+ g_return_if_fail (samples != NULL);
+
+ for (i = 0; i < curve->n_samples; i++)
+ samples[i] = curve->samples[i] * 255.999;
+}
+
+
+/* private functions */
+
+static void
+gimp_curve_calculate (GimpCurve *curve)
+{
+ gint i;
+ gint p1, p2, p3, p4;
+
+ if (gimp_data_is_frozen (GIMP_DATA (curve)))
+ return;
+
+ switch (curve->curve_type)
+ {
+ case GIMP_CURVE_SMOOTH:
+ /* Initialize boundary curve points */
+ if (curve->n_points > 0)
+ {
+ GimpCurvePoint point;
+ gint boundary;
+
+ point = curve->points[0];
+ boundary = ROUND (point.x * (gdouble) (curve->n_samples - 1));
+
+ for (i = 0; i < boundary; i++)
+ curve->samples[i] = point.y;
+
+ point = curve->points[curve->n_points - 1];
+ boundary = ROUND (point.x * (gdouble) (curve->n_samples - 1));
+
+ for (i = boundary; i < curve->n_samples; i++)
+ curve->samples[i] = point.y;
+ }
+
+ for (i = 0; i < curve->n_points - 1; i++)
+ {
+ p1 = MAX (i - 1, 0);
+ p2 = i;
+ p3 = i + 1;
+ p4 = MIN (i + 2, curve->n_points - 1);
+
+ if (curve->points[p2].type == GIMP_CURVE_POINT_CORNER)
+ p1 = p2;
+
+ if (curve->points[p3].type == GIMP_CURVE_POINT_CORNER)
+ p4 = p3;
+
+ gimp_curve_plot (curve, p1, p2, p3, p4);
+ }
+
+ /* ensure that the control points are used exactly */
+ for (i = 0; i < curve->n_points; i++)
+ {
+ gdouble x = curve->points[i].x;
+ gdouble y = curve->points[i].y;
+
+ curve->samples[ROUND (x * (gdouble) (curve->n_samples - 1))] = y;
+ }
+
+ g_object_notify (G_OBJECT (curve), "samples");
+ break;
+
+ case GIMP_CURVE_FREE:
+ break;
+ }
+}
+
+/*
+ * This function calculates the curve values between the control points
+ * p2 and p3, taking the potentially existing neighbors p1 and p4 into
+ * account.
+ *
+ * This function uses a cubic bezier curve for the individual segments and
+ * calculates the necessary intermediate control points depending on the
+ * neighbor curve control points.
+ */
+static void
+gimp_curve_plot (GimpCurve *curve,
+ gint p1,
+ gint p2,
+ gint p3,
+ gint p4)
+{
+ gint i;
+ gdouble x0, x3;
+ gdouble y0, y1, y2, y3;
+ gdouble dx, dy;
+ gdouble slope;
+
+ /* the outer control points for the bezier curve. */
+ x0 = curve->points[p2].x;
+ y0 = curve->points[p2].y;
+ x3 = curve->points[p3].x;
+ y3 = curve->points[p3].y;
+
+ /*
+ * the x values of the inner control points are fixed at
+ * x1 = 2/3*x0 + 1/3*x3 and x2 = 1/3*x0 + 2/3*x3
+ * this ensures that the x values increase linearly with the
+ * parameter t and enables us to skip the calculation of the x
+ * values altogether - just calculate y(t) evenly spaced.
+ */
+
+ dx = x3 - x0;
+ dy = y3 - y0;
+
+ if (dx <= EPSILON)
+ {
+ gint index;
+
+ index = ROUND (x0 * (gdouble) (curve->n_samples - 1));
+
+ curve->samples[index] = y3;
+
+ return;
+ }
+
+ if (p1 == p2 && p3 == p4)
+ {
+ /* No information about the neighbors,
+ * calculate y1 and y2 to get a straight line
+ */
+ y1 = y0 + dy / 3.0;
+ y2 = y0 + dy * 2.0 / 3.0;
+ }
+ else if (p1 == p2 && p3 != p4)
+ {
+ /* only the right neighbor is available. Make the tangent at the
+ * right endpoint parallel to the line between the left endpoint
+ * and the right neighbor. Then point the tangent at the left towards
+ * the control handle of the right tangent, to ensure that the curve
+ * does not have an inflection point.
+ */
+ slope = (curve->points[p4].y - y0) / (curve->points[p4].x - x0);
+
+ y2 = y3 - slope * dx / 3.0;
+ y1 = y0 + (y2 - y0) / 2.0;
+ }
+ else if (p1 != p2 && p3 == p4)
+ {
+ /* see previous case */
+ slope = (y3 - curve->points[p1].y) / (x3 - curve->points[p1].x);
+
+ y1 = y0 + slope * dx / 3.0;
+ y2 = y3 + (y1 - y3) / 2.0;
+ }
+ else /* (p1 != p2 && p3 != p4) */
+ {
+ /* Both neighbors are available. Make the tangents at the endpoints
+ * parallel to the line between the opposite endpoint and the adjacent
+ * neighbor.
+ */
+ slope = (y3 - curve->points[p1].y) / (x3 - curve->points[p1].x);
+
+ y1 = y0 + slope * dx / 3.0;
+
+ slope = (curve->points[p4].y - y0) / (curve->points[p4].x - x0);
+
+ y2 = y3 - slope * dx / 3.0;
+ }
+
+ /*
+ * finally calculate the y(t) values for the given bezier values. We can
+ * use homogeneously distributed values for t, since x(t) increases linearly.
+ */
+ for (i = 0; i <= ROUND (dx * (gdouble) (curve->n_samples - 1)); i++)
+ {
+ gdouble y, t;
+ gint index;
+
+ t = i / dx / (gdouble) (curve->n_samples - 1);
+ y = y0 * (1-t) * (1-t) * (1-t) +
+ 3 * y1 * (1-t) * (1-t) * t +
+ 3 * y2 * (1-t) * t * t +
+ y3 * t * t * t;
+
+ index = i + ROUND (x0 * (gdouble) (curve->n_samples - 1));
+
+ if (index < curve->n_samples)
+ curve->samples[index] = CLAMP (y, 0.0, 1.0);
+ }
+}