From afa05b51f4f8073e2fa69f4012484d1e33d05183 Mon Sep 17 00:00:00 2001
From: Vito Caputo <vcaputo@pengaru.com>
Date: Sun, 26 Aug 2018 17:26:02 -0700
Subject: v2f: Add a two-dimensional float vector header

---
 v2f.h | 87 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 87 insertions(+)
 create mode 100644 v2f.h

diff --git a/v2f.h b/v2f.h
new file mode 100644
index 0000000..5d9d561
--- /dev/null
+++ b/v2f.h
@@ -0,0 +1,87 @@
+/*
+ *  Copyright (C) 2018  Vito Caputo - <vcaputo@pengaru.com>
+ *
+ *  This program is free software: you can redistribute it and/or modify it
+ *  under the terms of the GNU General Public License version 3 as published
+ *  by the Free Software Foundation.
+ *
+ *  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/>.
+ */
+
+#ifndef _V2F_H
+#define _V2F_H
+
+#include <math.h>
+
+typedef struct v2f_t {
+	float	x, y;
+} v2f_t;
+
+
+static inline v2f_t v2f_add(const v2f_t *a, const v2f_t *b)
+{
+	return (v2f_t){a->x + b->x, a->y + b->y};
+}
+
+
+static inline v2f_t v2f_sub(const v2f_t *a, const v2f_t *b)
+{
+	return (v2f_t){a->x - b->x, a->y - b->y};
+}
+
+
+static inline v2f_t v2f_mult(const v2f_t *a, const v2f_t *b)
+{
+	return (v2f_t){a->x * b->x, a->y * b->y};
+}
+
+
+static inline v2f_t v2f_mult_scalar(const v2f_t *v, float scalar)
+{
+	return (v2f_t){ v->x * scalar, v->y * scalar };
+}
+
+
+static inline float v2f_dot(const v2f_t *a, const v2f_t *b)
+{
+	return a->x * b->x + a->y * b->y;
+}
+
+
+static inline float v2f_length(const v2f_t *v)
+{
+	return sqrtf(v2f_dot(v, v));
+}
+
+
+static inline v2f_t v2f_normalize(const v2f_t *v)
+{
+	return v2f_mult_scalar(v, 1.0f / v2f_length(v));
+}
+
+
+static inline v2f_t v2f_lerp(const v2f_t *a, const v2f_t *b, float t)
+{
+	v2f_t	lerp_a, lerp_b;
+
+	lerp_a = v2f_mult_scalar(a, 1.0f - t);
+	lerp_b = v2f_mult_scalar(b, t);
+
+	return v2f_add(&lerp_a, &lerp_b);
+}
+
+
+static inline v2f_t v2f_nlerp(const v2f_t *a, const v2f_t *b, float t)
+{
+	v2f_t	lerp = v2f_lerp(a, b, t);
+
+	return v2f_normalize(&lerp);
+}
+
+#endif
-- 
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