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/*!
    \example framebuffer
    \since QtCanvas3D 1.0
    \title Framebuffer Example
    \ingroup qtcanvas3d-examples
    \brief Render into a framebuffer and use it as a texture.

    The Framebuffer Example shows how to render into a framebuffer, create a
    texture of it, and apply the texture to an object in normal on-screen
    rendering.

    The example has a moving and rotating cube, which has another textured
    cube drawn into it via the framebuffer object. The cube in the framebuffer
    can be rotated using \l [QML] {Slider}s from \l {Qt Quick Controls}.

    \image framebuffer-example.png

    \section1 Preparing the Framebuffer

    We first define the variables we need for the render-to-texture
    framebuffer:

    \snippet framebuffer/qml/framebuffer/framebuffer.js 0

    Then, in the \c initializeGL function, we create the framebuffer object:

    \snippet framebuffer/qml/framebuffer/framebuffer.js 1

    \section1 Creating the Texture

    After the creation of the framebuffer, we create the texture:

    \snippet framebuffer/qml/framebuffer/framebuffer.js 2

    Then we need to bind the texture as a color attachment, create and bind
    a render buffer, and bind the depth attachment:

    \snippet framebuffer/qml/framebuffer/framebuffer.js 3

    \section1 Rendering into the Framebuffer

    In \c paintGL function, we first need to draw the scene into the
    framebuffer. We start by binding the framebuffer object and setting a
    viewport:

    \snippet framebuffer/qml/framebuffer/framebuffer.js 4

    Then, we need to bind the loaded texture we want to use in rendering
    into the framebuffer object:

    \snippet framebuffer/qml/framebuffer/framebuffer.js 5

    And then we can draw the textured cube into the framebuffer:

    \snippet framebuffer/qml/framebuffer/framebuffer.js 6

    \section1 Using the Framebuffer as a Texture

    First, we bind the render-to-texture right after drawing, and generate
    mipmaps:

    \snippet framebuffer/qml/framebuffer/framebuffer.js 7

    Then we need to bind the default framebuffer (screen), and set up the
    viewport:

    \snippet framebuffer/qml/framebuffer/framebuffer.js 8

    And finally, we draw the on-screen view:

    \snippet framebuffer/qml/framebuffer/framebuffer.js 9
 */