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/****************************************************************************
**
** Copyright (C) 2015 The Qt Company Ltd.
** Contact: http://www.qt.io/licensing/
**
** This file is part of the documentation of the Qt Toolkit.
**
** $QT_BEGIN_LICENSE:FDL$
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** accordance with the commercial license agreement provided with the
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** information use the contact form at http://www.qt.io/contact-us.
**
** GNU Free Documentation License Usage
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** Documentation License version 1.3 as published by the Free Software
** Foundation and appearing in the file included in the packaging of
** this file. Please review the following information to ensure
** the GNU Free Documentation License version 1.3 requirements
** will be met: http://www.gnu.org/copyleft/fdl.html.
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****************************************************************************/
/*!
\title Qt Quick Examples - Shader Effects
\example shadereffects
\image qml-shadereffects-example.png
\brief A Qt Quick example demonstrating the use of shader effects.
\ingroup qtquickexamples
This example demonstrates a couple of visual effects that you can perform
with shaders in Qt Quick. It applies five different effects on a text and
a couple of images. For more information, visit
\l{Important Concepts In Qt Quick - Graphical Effects}
\include examples-run.qdocinc
\section1 Using ShaderEffect
The \l ShaderEffect type typically operates on other types, using a
\l ShaderEffectSource:
\snippet shadereffects/shadereffects.qml source
In the above snippet, \c theItem is the ID of a complex QML object in the
file.
ShaderEffects can use this ShaderEffectSource as a texture in their fragment
shader:
\snippet shadereffects/shadereffects.qml fragment
In order to support multiple graphics APIs, not just OpenGL, the shader
source is not embedded into QML. Instead, file selectors are used to select
the correct variant at runtime. Based on the Qt Quick backend in use, Qt
will automatically select either \c{shaders/wobble.frag} with the GLSL
source code or \c{shaders/+hlsl/wobble.frag} with the HLSL source code.
\note For simplicity shader source code is used in all variants of the
files. However, with the Direct3D backend of Qt Quick pre-compiled shaders
are also supported. For example, try the following commands in the
\c{content/shaders/+hlsl} directory: \c{move wobble.frag wobble.frag.src}
followed by \c{fxc /E main /T ps_5_0 /Fo wobble.frag wobble.frag.src}. Now
\c wobble.frag contains Direct3D bytecode and that is what gets shipped
with the application instead of the shader source. Further changes are not
necessary, the application will function like before.
You can use any custom property on the ShaderEffect in your shader. This
makes animated shader code very easy:
\snippet shadereffects/shadereffects.qml properties
ShaderEffects can also have a custom vertext shader. Setting the mesh
property on ShaderEffect provides more vertices for you to manipulate,
enabling more effects.
\snippet shadereffects/shadereffects.qml vertex
*/
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