1 files changed, 116 insertions, 0 deletions
diff --git a/src/animation/gtd-interval.h b/src/animation/gtd-interval.h
new file mode 100644
index 0000000..efcfb03
--- /dev/null
+++ b/src/animation/gtd-interval.h
@@ -0,0 +1,116 @@
+/* gtd-interval.h
+ *
+ * Copyright 2020 Georges Basile Stavracas Neto <georges.stavracas@gmail.com>
+ *
+ * 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 <http://www.gnu.org/licenses/>.
+ *
+ * SPDX-License-Identifier: GPL-3.0-or-later
+ */
+
+#pragma once
+
+#include <glib-object.h>
+
+G_BEGIN_DECLS
+
+#define GTD_TYPE_INTERVAL (gtd_interval_get_type())
+G_DECLARE_DERIVABLE_TYPE (GtdInterval, gtd_interval, GTD, INTERVAL, GInitiallyUnowned)
+
+/**
+ * GtdIntervalClass:
+ * @validate: virtual function for validating an interval
+ *   using a #GParamSpec
+ * @compute_value: virtual function for computing the value
+ *   inside an interval using an adimensional factor between 0 and 1
+ *
+ * The #GtdIntervalClass contains only private data.
+ *
+ * Since: 1.0
+ */
+struct _GtdIntervalClass
+{
+  /*< private >*/
+  GInitiallyUnownedClass parent_class;
+
+  /*< public >*/
+  gboolean (* validate)      (GtdInterval *self,
+                              GParamSpec  *pspec);
+  gboolean (* compute_value) (GtdInterval *self,
+                              gdouble      factor,
+                              GValue      *value);
+
+  /*< private >*/
+  /* padding for future expansion */
+  void (*_gtd_reserved1) (void);
+  void (*_gtd_reserved2) (void);
+  void (*_gtd_reserved3) (void);
+  void (*_gtd_reserved4) (void);
+  void (*_gtd_reserved5) (void);
+  void (*_gtd_reserved6) (void);
+};
+
+GtdInterval*    gtd_interval_new                (GType gtype,
+                                                 ...);
+
+GtdInterval*    gtd_interval_new_with_values    (GType         gtype,
+                                                 const GValue *initial,
+                                                 const GValue *final);
+
+
+GtdInterval*     gtd_interval_clone              (GtdInterval *self);
+
+GType            gtd_interval_get_value_type     (GtdInterval *self);
+
+void             gtd_interval_set_initial        (GtdInterval *self,
+                                                      ...);
+
+void             gtd_interval_set_initial_value  (GtdInterval  *self,
+                                                  const GValue *value);
+
+void             gtd_interval_get_initial_value  (GtdInterval *self,
+                                                  GValue      *value);
+
+GValue*          gtd_interval_peek_initial_value (GtdInterval *self);
+
+void             gtd_interval_set_final          (GtdInterval *self,
+                                                  ...);
+
+void             gtd_interval_set_final_value    (GtdInterval  *self,
+                                                  const GValue *value);
+
+void             gtd_interval_get_final_value    (GtdInterval *self,
+                                                  GValue      *value);
+
+GValue*          gtd_interval_peek_final_value   (GtdInterval *self);
+
+void             gtd_interval_set_interval       (GtdInterval *self,
+                                                  ...);
+
+void             gtd_interval_get_interval       (GtdInterval *self,
+                                                  ...);
+
+gboolean         gtd_interval_validate           (GtdInterval *self,
+                                                  GParamSpec  *pspec);
+
+gboolean         gtd_interval_compute_value      (GtdInterval *self,
+                                                  gdouble      factor,
+                                                  GValue      *value);
+
+const GValue*    gtd_interval_compute            (GtdInterval *self,
+                                                  gdouble      factor);
+
+gboolean         gtd_interval_is_valid           (GtdInterval *self);
+
+
+G_END_DECLS