-
Notifications
You must be signed in to change notification settings - Fork 0
/
matrix.c
134 lines (107 loc) · 2.73 KB
/
matrix.c
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
/*
* =====================================================================================
*
* Filename: matrix.c
*
* Description: basic matrix operations
*
* Version: 1.0
* Created: 23.07.2011 04:17:49
* Revision: none
* Compiler: gcc
*
* Author: YOUR NAME (),
* Company:
*
* =====================================================================================
*/
#include "matrix.h"
GLfloat *create_matrix() {
GLfloat *return_value = malloc(sizeof(GLfloat) * 16);
GLfloat identity[] = {
1, 0, 0, 0,
0, 1, 0, 0,
0, 0, 1, 0,
0, 0, 0, 1
};
memcpy(return_value, identity, sizeof(GLfloat) * 16);
return return_value;
}
void destroy_matrix(GLfloat *matrix) {
//you have to free your mind, neo
free(matrix);
}
void load_identity(GLfloat matrix[16]) {
matrix[0] = 1.0f;
matrix[1] = 0.0f;
matrix[2] = 0.0f;
matrix[3] = 0.0f;
matrix[4] = 0.0f;
matrix[5] = 1.0f;
matrix[6] = 0.0f;
matrix[7] = 0.0f;
matrix[8] = 0.0f;
matrix[9] = 0.0f;
matrix[10] = 1.0f;
matrix[11] = 0.0f;
matrix[12] = 0.0f;
matrix[13] = 0.0f;
matrix[14] = 0.0f;
matrix[15] = 1.0f;
}
void multiply_matrix(GLfloat matrix[16], GLfloat matrix0[16], GLfloat matrix1[16]) {
GLuint i;
GLuint k;
GLuint l, m;
GLfloat temp[16];
for (i = 0; i < 16; i++) {
temp[i] = 0.0f;
l = i % 4;
m = (i / 4) * 4;
for (k = 0; k < 4; k++) {
temp[i] += matrix0[l] * matrix1[m];
l += 4;
m++;
}
}
for (i = 0; i < 16; i++) {
matrix[i] = temp[i];
}
}
void translate(GLfloat matrix[16], GLfloat x, GLfloat y, GLfloat z) {
GLfloat temp[16];
load_identity(temp);
temp[12] += x;
temp[13] += y;
temp[14] += z;
multiply_matrix(matrix, matrix, temp);
}
void scale(GLfloat *matrix, GLfloat x, GLfloat y, GLfloat z) {
GLfloat temp[16];
load_identity(temp);
temp[0] = x;
temp[5] = y;
temp[10] = z;
multiply_matrix(matrix, matrix, temp);
}
void rotate(GLfloat *matrix, GLfloat angle, GLfloat x, GLfloat y, GLfloat z) {
GLfloat temp[16];
GLfloat s = sinf(2.0f * (float)M_PI * angle / 360.0f);
GLfloat c = cosf(2.0f * (float)M_PI * angle / 360.0f);
vec3f vector = vec_create(x, y, z);
vec_normal(vector);
x = vector.x;
y = vector.y;
z = vector.z;
load_identity(temp);
temp[0] = x * x * (1 - c) + c;
temp[1] = x * y * (1 - c) + z * s;
temp[2] = x * z * (1 - c) - y * s;
temp[4] = x * y * (1 - c) - z * s;
temp[5] = y * y * (1 - c) + c;
temp[6] = y * z * (1 - c) + x * s;
temp[8] = x * z * (1 - c) + y * s;
temp[9] = y * z * (1 - c) - x * s;
temp[10] = z * z * (1 - c) + c;
multiply_matrix(matrix, matrix, temp);
}