blob: 5902cea9b931d142d0f7cfe8c52794b77e391df6 (
plain)
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
|
/*
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_Color;
attribute vec4 gtf_Vertex;
uniform mat4 gtf_ModelViewProjectionMatrix;
varying vec4 color;
void main (void)
{
const float M_PI = 3.14159265358979323846;
// Both are unit vectors
vec2 v1;
vec2 v2 = normalize(vec2(1.0, 1.0));
float theta = gtf_Color.g * 2.0 * M_PI;
float phi = gtf_Color.b * 2.0 * M_PI;
v1.x = cos(theta) * sin(phi);
v1.y = sin(theta) * sin(phi);
vec2 result;
float eta = 0.5;
float k = 1.0 - eta * eta * (1.0 - dot(v1, v2) * dot(v1, v2));
if(k < 0.0)
result = vec2(0.0);
else
result = eta * v1 - (eta * dot(v1, v2) + sqrt(k)) * v2;
color = vec4((result + 1.0) / 2.0, 0.0, 1.0);
gl_Position = gtf_ModelViewProjectionMatrix * gtf_Vertex;
}
|
