altos/draw: Add damage tracking

[fw/altos] / src / draw / ao_box.h

diff --git a/src/draw/ao_box.h b/src/draw/ao_box.h
new file mode 100644 (file)
index 0000000..bd3aabd
--- /dev/null
+++ b/src/draw/ao_box.h
@@ -0,0 +1,50 @@
+/*
+ * Copyright © 2023 Keith Packard <keithp@keithp.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 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.,
+ * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
+ */
+
+#ifndef _AO_BOX_H_
+#define _AO_BOX_H_
+
+#include <stdint.h>
+#include <stdbool.h>
+
+struct ao_box {
+       int16_t         x1, y1;
+       int16_t         x2, y2;
+};
+
+static inline bool
+ao_box_is_empty(struct ao_box *box)
+{
+       return box->x1 == INT16_MAX;
+}
+
+static inline void
+ao_box_set_empty(struct ao_box *box)
+{
+       box->x1 = INT16_MAX;
+       box->y1 = INT16_MAX;
+       box->x2 = INT16_MIN;
+       box->y2 = INT16_MIN;
+}
+
+#define AO_BOX_INIT    { .x1 = INT16_MAX, .y1 = INT16_MAX, .x2 = INT16_MIN, .y2 = INT16_MIN }
+
+void
+ao_box_union(struct ao_box *dst, int16_t x1, int16_t y1, int16_t x2, int16_t y2);
+
+#endif /* _AO_BOX_H_ */