mat4_lookat

Makefile

@@ -6,7 +6,7 @@
 #    By: gbrochar <gbrochar@student.42.fr>          +#+  +:+       +#+         #
 #                                                 +#+#+#+#+#+   +#+            #
 #    Created: 2020/12/17 19:47:03 by gbrochar          #+#    #+#              #
-#    Updated: 2020/12/23 10:49:53 by gbrochar         ###   ########.fr        #
+#    Updated: 2020/12/23 17:05:36 by gbrochar         ###   ########.fr        #
 #                                                                              #
 # **************************************************************************** #
 
@@ -18,6 +18,8 @@ SRC_FILE =	main.c \
 			env.c \
 			mat4_transpose.c \
 			mat4_multiply.c \
+			mat4_perspective.c \
+			mat4_lookat.c \
 
 OBJ_FILE =	$(SRC_FILE:.c=.o)
 
@@ -31,7 +33,7 @@ SRC =		$(addprefix $(SRC_DIR), $(SRC_FILE))
 OBJ =		$(addprefix $(OBJ_DIR), $(OBJ_FILE))
 INC =		$(addprefix $(INC_DIR), $(INC_FILE))
 
-LIB =		
+LIB =		-lm
 
 CC =		gcc
 

inc/mat4.h

@@ -6,7 +6,7 @@
 /*   By: gbrochar <gbrochar@student.42.fr>          +#+  +:+       +#+        */
 /*                                                +#+#+#+#+#+   +#+           */
 /*   Created: 2020/12/22 20:35:00 by gbrochar          #+#    #+#             */
-/*   Updated: 2020/12/23 16:12:55 by gbrochar         ###   ########.fr       */
+/*   Updated: 2020/12/23 17:04:47 by gbrochar         ###   ########.fr       */
 /*                                                                            */
 /* ************************************************************************** */
 
@@ -14,6 +14,7 @@
 # define MAT4_H
 
 # include "vec4.h"
+# include <math.h>
 
 typedef struct s_mat4		t_mat4;
 typedef struct s_persp_tool	t_persp_tool;

inc/scop.h

@@ -6,7 +6,7 @@
 /*   By: gbrochar <gbrochar@student.42.fr>          +#+  +:+       +#+        */
 /*                                                +#+#+#+#+#+   +#+           */
 /*   Created: 2020/12/22 12:08:22 by gbrochar          #+#    #+#             */
-/*   Updated: 2020/12/22 20:15:56 by gbrochar         ###   ########.fr       */
+/*   Updated: 2020/12/23 16:23:16 by gbrochar         ###   ########.fr       */
 /*                                                                            */
 /* ************************************************************************** */
 
@@ -25,6 +25,8 @@
 
 # define BUFFER_SIZE 4096
 
+# define EPSILON 0.000001
+
 typedef enum e_gl_buf_type	t_gl_buf_type;
 
 enum						e_gl_buf_type

inc/vec3.h

@@ -0,0 +1,25 @@
+/* ************************************************************************** */
+/*                                                                            */
+/*                                                        :::      ::::::::   */
+/*   vec3.h                                             :+:      :+:    :+:   */
+/*                                                    +:+ +:+         +:+     */
+/*   By: gbrochar <gbrochar@student.42.fr>          +#+  +:+       +#+        */
+/*                                                +#+#+#+#+#+   +#+           */
+/*   Created: 2020/12/23 16:14:13 by gbrochar          #+#    #+#             */
+/*   Updated: 2020/12/23 16:14:28 by gbrochar         ###   ########.fr       */
+/*                                                                            */
+/* ************************************************************************** */
+
+#ifndef VEC3_H
+# define VEC3_H
+
+typedef struct s_vec3		t_vec3;
+
+struct						s_vec3
+{
+	double					x;
+	double					y;
+	double					z;
+};
+
+#endif

src/mat4_lookat.c

@@ -0,0 +1,125 @@
+/* ************************************************************************** */
+/*                                                                            */
+/*                                                        :::      ::::::::   */
+/*   mat4_lookat.c                                      :+:      :+:    :+:   */
+/*                                                    +:+ +:+         +:+     */
+/*   By: gbrochar <gbrochar@student.42.fr>          +#+  +:+       +#+        */
+/*                                                +#+#+#+#+#+   +#+           */
+/*   Created: 2020/12/23 16:14:47 by gbrochar          #+#    #+#             */
+/*   Updated: 2020/12/23 17:05:21 by gbrochar         ###   ########.fr       */
+/*                                                                            */
+/* ************************************************************************** */
+
+#include "mat4.h"
+#include "vec3.h"
+#include "scop.h"
+
+t_mat4			mat4_lookat_make_mat(t_vec3 x, t_vec3 y, t_vec3 z, t_vec3 eye)
+{
+	t_mat4		ret;
+
+	ret.data[0] = x.x;
+	ret.data[1] = x.y;
+	ret.data[2] = x.z;
+	ret.data[3] = 0;
+	ret.data[4] = y.x;
+	ret.data[5] = y.y;
+	ret.data[6] = y.z;
+	ret.data[7] = 0;
+	ret.data[8] = z.x;
+	ret.data[9] = z.y;
+	ret.data[10] = z.z;
+	ret.data[11] = 0;
+	ret.data[12] = -(x.x * eye.x + x.y * eye.y + x.z * eye.z);
+	ret.data[13] = -(y.x * eye.x + y.y * eye.y + y.z * eye.z);
+	ret.data[14] = -(z.x * eye.x + z.y * eye.y + z.z * eye.z);
+	ret.data[15] = 1;
+	return (ret);
+}
+
+t_vec3			mat4_lookat_make_y(t_vec3 x, t_vec3 z)
+{
+	t_vec3		y;
+	double		len;
+
+	y.x = z.y * x.z - z.z * x.y;
+	y.y = z.z * x.x - z.x * x.z;
+	y.z = z.x * x.y - z.y * x.x;
+	len = y.x * y.x + y.y * y.y + y.z * y.z;
+	if (len - EPSILON < 0 && len + EPSILON > 0)
+	{
+		y.x = 0;
+		y.y = 0;
+		y.z = 0;
+	}
+	else
+	{
+		len = 1.0 / sqrt(len);
+		y.x *= len;
+		y.y *= len;
+		y.z *= len;
+	}
+	return (y);
+}
+
+t_vec3			mat4_lookat_make_x(t_vec3 z, t_vec3 up)
+{
+	t_vec3		x;
+	double		len;
+
+	x.x = up.y * z.z - up.z * z.y;
+	x.y = up.z * z.x - up.x * z.z;
+	x.z = up.x * z.y - up.y * z.x;
+	len = x.x * x.x + x.y * x.y + x.z * x.z;
+	if (len - EPSILON < 0 && len + EPSILON > 0)
+	{
+		x.x = 0;
+		x.y = 0;
+		x.z = 0;
+	}
+	else
+	{
+		len = 1.0 / sqrt(len);
+		x.x *= len;
+		x.y *= len;
+		x.z *= len;
+	}
+	return (x);
+}
+
+t_vec3			mat4_lookat_make_z(t_vec3 eye, t_vec3 target)
+{
+	t_vec3		z;
+	double		len;
+
+	z.x = eye.x - target.x;
+	z.y = eye.y - target.y;
+	z.z = eye.z - target.z;
+	len = z.x * z.x + z.y * z.y + z.z * z.z;
+	if (len - EPSILON < 0 && len + EPSILON > 0)
+	{
+		z.x = 0;
+		z.y = 0;
+		z.z = 1;
+	}
+	else
+	{
+		len = 1.0 / sqrt(len);
+		z.x *= len;
+		z.y *= len;
+		z.z *= len;
+	}
+	return (z);
+}
+
+t_mat4			mat4_lookat(t_vec3 eye, t_vec3 up, t_vec3 target)
+{
+	t_vec3		z;
+	t_vec3		x;
+	t_vec3		y;
+
+	z = mat4_lookat_make_z(eye, target);
+	x = mat4_lookat_make_x(z, up);
+	y = mat4_lookat_make_y(x, z);
+	return (mat4_lookat_make_mat(x, y, z, eye));
+}