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
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
|
// SPDX-License-Identifier: GPL-2.0-or-later
/* SPDX-FileCopyrightText: 2004-2015 Simon Wunderlich <sw@simonwunderlich.de>
*/
/* this file gives some simple matrix functionality for things I was unable */
/* to do with OpenGL */
#include "global.h"
#include <string.h> /* memcpy() */
#define DEG2RAD (M_PI/180.0)
static t_mtrx MAT;
t_mtrx Identity = {
1.0, 0.0, 0.0, 0.0,
0.0, 1.0, 0.0, 0.0,
0.0, 0.0, 1.0, 0.0,
0.0, 0.0, 0.0, 1.0
};
void myLoadIdentity(void)
{
memcpy(MAT, Identity, sizeof(t_mtrx));
}
#define I(x, y) x*4+y
#define M(x, y) MAT[I(x, y)]
static void mat_debug(t_mtrx S)
{
s3dprintf(MED, "MAT_0: %.2f %.2f %.2f %.2f", S[I(0, 0)], S[I(1, 0)], S[I(2, 0)], S[I(3, 0)]);
s3dprintf(MED, "MAT_1: %.2f %.2f %.2f %.2f", S[I(0, 1)], S[I(1, 1)], S[I(2, 1)], S[I(3, 1)]);
s3dprintf(MED, "MAT_2: %.2f %.2f %.2f %.2f", S[I(0, 2)], S[I(1, 2)], S[I(2, 2)], S[I(3, 2)]);
s3dprintf(MED, "MAT_3: %.2f %.2f %.2f %.2f", S[I(0, 3)], S[I(1, 3)], S[I(2, 3)], S[I(3, 3)]);
}
void myMultMatrix(t_mtrx mat2)
{
int i, j, k;
t_mtrx mat_d; /* destination matrix */
for (i = 0; i < 4; i++)
for (j = 0; j < 4; j++) {
mat_d[I(i, j)] = 0.0F;
for (k = 0; k < 4; k++)
mat_d[I(i, j)] += M(k, j) * mat2[I(i, k)];
}
memcpy(MAT, mat_d, sizeof(t_mtrx));
}
void myGetMatrix(t_mtrx mat)
{
memcpy(mat, MAT, sizeof(t_mtrx));
}
void mySetMatrix(t_mtrx mat)
{
memcpy(MAT, mat, sizeof(t_mtrx));
}
void myTransform4f(float *v)
{
float w[4];
w[0] = v[0] * M(0, 0) + v[1] * M(1, 0) + v[2] * M(2, 0) + v[3] * M(3, 0);
w[1] = v[0] * M(0, 1) + v[1] * M(1, 1) + v[2] * M(2, 1) + v[3] * M(3, 1);
w[2] = v[0] * M(0, 2) + v[1] * M(1, 2) + v[2] * M(2, 2) + v[3] * M(3, 2);
w[3] = v[0] * M(0, 3) + v[1] * M(1, 3) + v[2] * M(2, 3) + v[3] * M(3, 3);
memcpy(v, w, sizeof(w));
}
void myTransform3f(float *v)
{
float w[3];
w[0] = v[0] * M(0, 0) + v[1] * M(1, 0) + v[2] * M(2, 0) + 1.0F * M(3, 0);
w[1] = v[0] * M(0, 1) + v[1] * M(1, 1) + v[2] * M(2, 1) + 1.0F * M(3, 1);
w[2] = v[0] * M(0, 2) + v[1] * M(1, 2) + v[2] * M(2, 2) + 1.0F * M(3, 2);
memcpy(v, w, sizeof(w));
}
void myTransformV(struct t_vertex *v)
{
struct t_vertex w;
w.x = v->x * M(0, 0) + v->y * M(1, 0) + v->z * M(2, 0) + 1.0F * M(3, 0);
w.y = v->x * M(0, 1) + v->y * M(1, 1) + v->z * M(2, 1) + 1.0F * M(3, 1);
w.z = v->x * M(0, 2) + v->y * M(1, 2) + v->z * M(2, 2) + 1.0F * M(3, 2);
memcpy(v, &w, sizeof(struct t_vertex));
}
#undef M
#define M(x, y) Mm[I(x, y)]
#define P(x, y) Pm[I(x, y)]
/* this inverts the matrix M into P in the gauss way */
int myInvert(void)
{
t_mtrx Mm, Pm;
int l, lh; /* line */
float f; /* factor */
int i; /* number */
memcpy(Mm, MAT, sizeof(t_mtrx)); /* backup matrix */
memcpy(Pm, Identity, sizeof(t_mtrx)); /* target */
/* step 1 */
for (l = 0; l < 4; l++) {
check:
if (M(l, l) * M(l, l) > 0.00000001F) { /* it won't work with real zero */
/* s3dprintf(MED,"normalizing line %d",l); */
/* normalize */
f = 1 / M(l, l);
M(l, l) = 1.0;
for (i = l + 1; i < 4; i++)
M(i, l) *= f; /* the left side ... */
for (i = 0; i < 4; i++)
P(i, l) *= f; /* ... and the right */
/* mult/fac */
for (lh = l + 1; lh < 4; lh++) {
if (M(l, lh) != 0) { /* "first" element of the line */
f = -M(l, lh);
M(l, lh) = 0.0; /* yes, this WILL be zero! ... */
for (i = l + 1; i < 4; i++) /* left side */
M(i, lh) += f * M(i, l);
for (i = 0; i < 4; i++) /* ... and the right one! */
P(i, lh) += f * P(i, l);
}
}
} else {
M(l, l) = 0.0F;
for (lh = l + 1; lh < 4; lh++)
if (M(l, lh) != 0.0) {
for (i = 0; i < 4; i++) {
f = M(i, l);
M(i, l) = M(i, lh);
M(i, lh) = f;
f = P(i, l);
P(i, l) = P(i, lh);
P(i, lh) = f;
}
goto check;
}
s3dprintf(MED, "nothing to swap, can't reverse this matrix! returning ... ");
mat_debug(Mm);
return -1; /* the dead end!! */
}
}
/* matrix should look like this now: */
/* (1???|????)
* (01??|????)
* (001?|????)
* (0001|????)
*
* (M = left side, P = right side)
* */
/* step 2 */
for (l = 3; l > 0; l--) {
/* mult/fac */
for (lh = l - 1; lh >= 0; lh--) {
if (M(l, lh) != 0) { /* "first" element of the line */
f = -M(l, lh);
M(l, lh) = 0;
for (i = 0; i < 4; i++) { /* ... and the right one! */
P(i, lh) += f * P(i, l);
}
}
}
}
/* now, Mm,is Identity and Pm is result! */
memcpy(MAT, Pm, sizeof(t_mtrx)); /* copy result */
return 0;
}
|
