--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/libcore/core/maths.c	Mon Oct 05 13:25:06 2020 +0200
@@ -0,0 +1,44 @@
+/*
+ * maths.c -- basic maths
+ *
+ * Copyright (c) 2020 David Demelier <markand@malikania.fr>
+ *
+ * Permission to use, copy, modify, and/or distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+
+#include "maths.h"
+
+bool
+maths_is_boxed(int x, int y, unsigned int w, unsigned int h, int px, int py)
+{
+	return px >= x &&
+	       py >= y &&
+	       px <= x + w &&
+	       py <= y + h;
+}
+
+void
+maths_centerize(int *x,
+               int *y,
+               unsigned int w,
+               unsigned int h,
+               int px,
+               int py,
+               unsigned int pw,
+               unsigned int ph)
+{
+	if (x)
+		*x = px + (pw / 2) - (w / 2);
+	if (y)
+		*y = py + (ph / 2) - (h / 2);
+}