summaryrefslogtreecommitdiffstats
path: root/examples/multimedia/video/qmlvideofx/shaders/magnify.fsh
blob: fb7e2a04759c43df806d4fcbed840ff02e9c2d7f (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
63
64
65
66
67
68
69
70
71
/****************************************************************************
**
** Copyright (C) 2013 Digia Plc and/or its subsidiary(-ies).
** Contact: http://www.qt-project.org/legal
**
** This file is part of the Qt Mobility Components.
**
** $QT_BEGIN_LICENSE:LGPL$
** Commercial License Usage
** Licensees holding valid commercial Qt licenses may use this file in
** accordance with the commercial license agreement provided with the
** Software or, alternatively, in accordance with the terms contained in
** a written agreement between you and Digia.  For licensing terms and
** conditions see http://qt.digia.com/licensing.  For further information
** use the contact form at http://qt.digia.com/contact-us.
**
** GNU Lesser General Public License Usage
** Alternatively, this file may be used under the terms of the GNU Lesser
** General Public License version 2.1 as published by the Free Software
** Foundation and appearing in the file LICENSE.LGPL included in the
** packaging of this file.  Please review the following information to
** ensure the GNU Lesser General Public License version 2.1 requirements
** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
**
** In addition, as a special exception, Digia gives you certain additional
** rights.  These rights are described in the Digia Qt LGPL Exception
** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
**
** GNU General Public License Usage
** Alternatively, this file may be used under the terms of the GNU
** General Public License version 3.0 as published by the Free Software
** Foundation and appearing in the file LICENSE.GPL included in the
** packaging of this file.  Please review the following information to
** ensure the GNU General Public License version 3.0 requirements will be
** met: http://www.gnu.org/copyleft/gpl.html.
**
**
** $QT_END_LICENSE$
**
****************************************************************************/

// Based on http://www.reddit.com/r/programming/comments/losip/shader_toy/c2upn1e

uniform sampler2D source;
uniform lowp float qt_Opacity;
varying vec2 qt_TexCoord0;
uniform float radius;
uniform float diffractionIndex;
uniform float targetWidth;
uniform float targetHeight;
uniform float posX;
uniform float posY;
uniform float pixDens;

void main()
{
    vec2 tc = qt_TexCoord0;
    vec2 center = vec2(posX, posY);
    vec2 xy = gl_FragCoord.xy - center.xy;
    xy.x -= (pixDens * 14.0);
    xy.y -= (pixDens * 29.0);
    float r = sqrt(xy.x * xy.x + xy.y * xy.y);
    if (r < radius) {
        float h = diffractionIndex * 0.5 * radius;
        vec2 new_xy = r < radius ? xy * (radius - h) / sqrt(radius * radius - r * r) : xy;
        vec2 targetSize = vec2(targetWidth, targetHeight);
        tc = (new_xy + center) / targetSize;
        tc.y = 1.0 - tc.y;
    }
    gl_FragColor = qt_Opacity * texture2D(source, tc);
}