JUCE/modules/juce_opengl/utils/juce_OpenGLAppComponent.h

/*
  ==============================================================================

   This file is part of the JUCE library.
   Copyright (c) 2017 - ROLI Ltd.

   JUCE is an open source library subject to commercial or open-source
   licensing.

   By using JUCE, you agree to the terms of both the JUCE 5 End-User License
   Agreement and JUCE 5 Privacy Policy (both updated and effective as of the
   27th April 2017).

   End User License Agreement: www.juce.com/juce-5-licence
   Privacy Policy: www.juce.com/juce-5-privacy-policy

   Or: You may also use this code under the terms of the GPL v3 (see
   www.gnu.org/licenses).

   JUCE IS PROVIDED "AS IS" WITHOUT ANY WARRANTY, AND ALL WARRANTIES, WHETHER
   EXPRESSED OR IMPLIED, INCLUDING MERCHANTABILITY AND FITNESS FOR PURPOSE, ARE
   DISCLAIMED.

  ==============================================================================
*/

#pragma once


//==============================================================================
/**
    A base class for writing simple one-page graphical apps.

    A subclass can inherit from this and implement just a few methods such as
    paint() and mouse-handling. The base class provides some simple abstractions
    to take care of continuously repainting itself.
*/
class JUCE_API  OpenGLAppComponent   : public Component,
                                       private OpenGLRenderer
{
public:
    OpenGLAppComponent();

    /** Destructor. */
    ~OpenGLAppComponent();

    /** Returns the number of times that the render method has been called since
        the component started running.
    */
    int getFrameCounter() const noexcept        { return frameCounter; }

    /** This must be called from your subclass's destructor, to shut down
        the GL system and stop it calling render() before your class is destroyed.
    */
    void shutdownOpenGL();

    /** Implement this method to set up any GL objects that you need for rendering.
        The GL context will be active when this method is called.
    */
    virtual void initialise() = 0;

    /** Implement this method to free any GL objects that you created during rendering.
        The GL context will still be active when this method is called.
    */
    virtual void shutdown() = 0;

    /** Called to render your openGL.
        @see OpenGLRenderer::render()
    */
    virtual void render() = 0;

    /** The GL context */
    OpenGLContext openGLContext;

private:
    //==============================================================================
    int frameCounter = 0;

    void newOpenGLContextCreated() override;
    void renderOpenGL() override;
    void openGLContextClosing() override;

    JUCE_DECLARE_NON_COPYABLE_WITH_LEAK_DETECTOR (OpenGLAppComponent)
};