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
|
/*
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.
*/
attribute vec4 gtf_Vertex;
uniform mat4 gtf_ModelViewProjectionMatrix;
varying vec4 color;
#define ERROR_EPSILON 0.1
void main (void)
{
vec4 L1 = vec4(1.0, 2.0, 3.0, 4.0);
vec4 L2 = vec4(5.0, 6.0, 7.0, 8.0);
vec4 L3 = vec4(9.0, 10.0, 11.0, 12.0);
vec4 L4 = vec4(13.0, 14.0, 15.0, 16.0);
mat4 a = mat4(L1,L2,L3,L4);
float gray,sum1=0.0,sum2=0.0,sum3=0.0,sum4=0.0;
int i;
sum1 = sum1 + a[0][0];
sum2 = sum2 + a[1][0];
sum3 = sum3 + a[2][0];
sum4 = sum4 + a[3][0];
sum1 = sum1 + a[0][1];
sum2 = sum2 + a[1][1];
sum3 = sum3 + a[2][1];
sum4 = sum4 + a[3][1];
sum1 = sum1 + a[0][2];
sum2 = sum2 + a[1][2];
sum3 = sum3 + a[2][2];
sum4 = sum4 + a[3][2];
sum1 = sum1 + a[0][3];
sum2 = sum2 + a[1][3];
sum3 = sum3 + a[2][3];
sum4 = sum4 + a[3][3];
if( ( sum1 > 10.0-ERROR_EPSILON && sum1 < 10.0+ERROR_EPSILON ) &&
( sum2 > 26.0-ERROR_EPSILON && sum2 < 26.0+ERROR_EPSILON) &&
( sum3 > 42.0-ERROR_EPSILON && sum3 < 42.0+ERROR_EPSILON) &&
( sum4 > 58.0-ERROR_EPSILON && sum4 < 58.0+ERROR_EPSILON) )
gray=1.0;
else gray=0.0;
color = vec4(gray, gray, gray, 1.0);
gl_Position = gtf_ModelViewProjectionMatrix * gtf_Vertex;
}
|
