blob: 8d08d9077cb20048cd005e1381bdd944aecae1b9 (
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
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
|
/*
* ***** BEGIN GPL LICENSE BLOCK *****
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version 2
* of the License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software Foundation,
* Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
*
* The Original Code is Copyright (C) 2001-2002 by NaN Holding BV.
* All rights reserved.
*
* The Original Code is: all of this file.
*
* Contributor(s): none yet.
*
* ***** END GPL LICENSE BLOCK *****
*/
/** \file RAS_Prewitt2DFilter.h
* \ingroup bgerastoglfilters
*/
#ifndef __RAS_PREWITT2DFILTER
#define __RAS_PREWITT2DFILTER
const char * PrewittFragmentShader=STRINGIFY(
uniform sampler2D bgl_RenderedTexture;
uniform vec2 bgl_TextureCoordinateOffset[9];
void main(void)
{
vec4 sample[9];
for (int i = 0; i < 9; i++)
{
sample[i] = texture2D(bgl_RenderedTexture,
gl_TexCoord[0].st + bgl_TextureCoordinateOffset[i]);
}
vec4 horizEdge = sample[2] + sample[5] + sample[8] -
(sample[0] + sample[3] + sample[6]);
vec4 vertEdge = sample[0] + sample[1] + sample[2] -
(sample[6] + sample[7] + sample[8]);
gl_FragColor.rgb = sqrt((horizEdge.rgb * horizEdge.rgb) +
(vertEdge.rgb * vertEdge.rgb));
gl_FragColor.a = 1.0;
}
);
#endif
|
