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++ // Copyright (C) 2017 The Qt Company Ltd.
++ // SPDX-License-Identifier: LicenseRef-Qt-Commercial OR GFDL-1.3-no-invariants-only
++
++ /*!
++ \title QQuickRenderControl OpenGL Example
++ \example rendercontrol/rendercontrol_opengl
++ \brief Shows how to render a Qt Quick scene into a texture that is then used by a non-Quick based OpenGL renderer.
++ \examplecategory {Graphics}
++
++ \image rendercontrol-opengl-example.jpg {3D cube with Qt Quick
++ content rendered as texture on each face}
++
++ The Qt Quick scene is managed by a QQuickWindow that is not visible
++ on-screen. Rather, rendering targets an OpenGL texture and is controlled
++ through QQuickRenderControl.
++
++ The cube is rendered directly with OpenGL, using Qt Gui enablers such as
++ QWindow, QOpenGLContext, QOpenGLShaderProgram, and QOpenGLFunctions. The
++ cube is textured with the texture that the Qt Quick render pass outputs to.
++
++ In addition, basic input event forwarding is also demonstrated. When holding
++ down the left mouse button, the background \l Rectangle color is altered via
++ QML bindings. Similarly, holding down a key on the keyboard changes the
++ color as well. This proves that the "fake" events sent from the application
++ (generated based on events from the on-screen QWindow) are forwarded and
++ processed within the Qt Quick scene.
++ */