1 files changed, 70 insertions, 0 deletions
diff --git a/vendor/libftm/src/mat4/ftm_mat4rotate.c b/vendor/libftm/src/mat4/ftm_mat4rotate.c
new file mode 100644
index 0000000..0a39c16
--- /dev/null
+++ b/vendor/libftm/src/mat4/ftm_mat4rotate.c
@@ -0,0 +1,70 @@
+/* ************************************************************************** */
+/*                                                                            */
+/*                                                        :::      ::::::::   */
+/*   ftm_mat4rotate.c                                   :+:      :+:    :+:   */
+/*                                                    +:+ +:+         +:+     */
+/*   By: charles <charles.cabergs@gmail.com>        +#+  +:+       +#+        */
+/*                                                +#+#+#+#+#+   +#+           */
+/*   Created: 2020/05/12 11:44:18 by charles           #+#    #+#             */
+/*   Updated: 2020/05/12 14:05:18 by charles          ###   ########.fr       */
+/*                                                                            */
+/* ************************************************************************** */
+
+#include "libftm_mat4.h"
+
+/*
+** Rotation axis/vector [x, y, z]
+**
+** 1st column:
+** | cos(θ) + x^2 (1 − cos(θ))   |
+** | y x (1 − cos(θ)) + z sin(θ) |
+** | z x (1 − cos(θ)) − y sin(θ) |
+** | 0                           |
+**
+** 2nd column:
+** | x y (1 − cos(θ)) − z sin(θ) |
+** | cos(θ) + y^2 (1 − cos(θ))   |
+** | z y (1 − cos(θ)) + x sin(θ) |
+** | 0                           |
+**
+** 3rd column:
+** | x z (1 − cos(θ)) + y sin(θ) |
+** | y z (1 − cos(θ)) − x sin(θ) |
+** | cos(θ) + z^2 (1 − cos(θ))   |
+** | 0                           |
+*/
+
+t_ftmmat4	*ftm_mat4rotate(t_ftmmat4 *mat4, float theta, t_ftmvec3 *axis)
+{
+	float		x;
+	float		y;
+	float		z;
+	float		sin_t;
+	float		cos_t;
+	t_ftmmat4	rot;
+
+	x = axis->v[0];
+	y = axis->v[1];
+	z = axis->v[2];
+	sin_t = sin(theta);
+	cos_t = cos(theta);
+	ftm_mat4init_fill(&rot, 0.0);
+	ftm_mat4set(&rot, 0, 0, cos_t + x * x * (1 - cos_t));
+	ftm_mat4set(&rot, 1, 0, y * x * (1 - cos_t) + z * sin_t);
+	ftm_mat4set(&rot, 2, 0, z * x * (1 - cos_t) + y * sin_t);
+	ftm_mat4set(&rot, 3, 0, 0.0);
+
+	ftm_mat4set(&rot, 0, 1, x * y * (1 - cos_t) - z * sin_t);
+	ftm_mat4set(&rot, 1, 1, cos_t + y * y * (1 - cos_t));
+	ftm_mat4set(&rot, 2, 1, z * y * (1 - cos_t) + x * sin_t);
+	ftm_mat4set(&rot, 3, 1, 0);
+
+	ftm_mat4set(&rot, 0, 2, x * z * (1 - cos_t) + y * sin_t);
+	ftm_mat4set(&rot, 1, 2, y * z * (1 - cos_t) - x * sin_t);
+	ftm_mat4set(&rot, 2, 2, cos_t + z * z * (1 - cos_t));
+	ftm_mat4set(&rot, 3, 2, 0);
+
+	ftm_mat4set(&rot, 3, 3, 1.0);
+	ftm_mat4mul(mat4, &rot);
+	return (mat4);
+}