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
|
/*
Copyright (c) 2019 The Khronos Group Inc.
Use of this source code is governed by an MIT-style license that can be
found in the LICENSE.txt file.
*/
#ifdef GL_ES
precision mediump float;
#endif
varying vec4 color;
// Function declaration.
mat4 function(in mat4 par);
bool is_all(const in mat4 par, const in float value);
void set_all(out mat4 par, const in float value);
void main (void)
{
mat4 par = mat4(1.0, 1.0, 1.0, 1.0,
1.0, 1.0, 1.0, 1.0,
1.0, 1.0, 1.0, 1.0,
1.0, 1.0, 1.0, 1.0);
mat4 ret = mat4(0.0, 0.0, 0.0, 0.0,
0.0, 0.0, 0.0, 0.0,
0.0, 0.0, 0.0, 0.0,
0.0, 0.0, 0.0, 0.0);
float gray = 0.0;
ret = function(par);
// The parameter should remain unchanged by the function and the function should return 1.0.
if(is_all(par, 1.0) && is_all(ret, 1.0))
{
gray = 1.0;
}
gl_FragColor = vec4(gray, gray, gray, 1.0);
}
// Function definition.
mat4 function(in mat4 par)
{
// Return the value of the parameter.
if(is_all(par, 1.0))
{
// Test parameter qualifier (default is "in").
set_all(par, 0.0);
return mat4(1.0, 1.0, 1.0, 1.0,
1.0, 1.0, 1.0, 1.0,
1.0, 1.0, 1.0, 1.0,
1.0, 1.0, 1.0, 1.0);
}
else
return mat4(0.0, 0.0, 0.0, 0.0,
0.0, 0.0, 0.0, 0.0,
0.0, 0.0, 0.0, 0.0,
0.0, 0.0, 0.0, 0.0);
}
bool is_all(const in mat4 par, const in float value)
{
bool ret = true;
if(par[0][0] != value)
ret = false;
if(par[0][1] != value)
ret = false;
if(par[0][2] != value)
ret = false;
if(par[0][3] != value)
ret = false;
if(par[1][0] != value)
ret = false;
if(par[1][1] != value)
ret = false;
if(par[1][2] != value)
ret = false;
if(par[1][3] != value)
ret = false;
if(par[2][0] != value)
ret = false;
if(par[2][1] != value)
ret = false;
if(par[2][2] != value)
ret = false;
if(par[2][3] != value)
ret = false;
if(par[3][0] != value)
ret = false;
if(par[3][1] != value)
ret = false;
if(par[3][2] != value)
ret = false;
if(par[3][3] != value)
ret = false;
return ret;
}
void set_all(out mat4 par, const in float value)
{
par[0][0] = value;
par[0][1] = value;
par[0][2] = value;
par[0][3] = value;
par[1][0] = value;
par[1][1] = value;
par[1][2] = value;
par[1][3] = value;
par[2][0] = value;
par[2][1] = value;
par[2][2] = value;
par[2][3] = value;
par[3][0] = value;
par[3][1] = value;
par[3][2] = value;
par[3][3] = value;
}
|
