gl/src/gl/Context.h

//
//  Created by Bradley Austin Davis on 2016/08/21
//  Copyright 2013-2016 High Fidelity, Inc.
//
//  Distributed under the Apache License, Version 2.0.
//  See the accompanying file LICENSE or http://www.apache.org/licenses/LICENSE-2.0.html
//
 
#ifndef hifi_gl_context_h
#define hifi_gl_context_h
 
#include <stdint.h>
#include <QtGlobal>
#include <atomic>
 
#if defined(Q_OS_WIN)
#include <Windows.h>
#endif
 
class QSurface;
class QWindow;
class QOpenGLContext;
class QThread;
class QOpenGLDebugMessage;
 
namespace gl {
 
    class Context {
    protected:
        QWindow* _window { nullptr };
        static void destroyContext(QOpenGLContext* context);
#ifdef Q_OS_WIN
        static bool USE_CUSTOM_CONTEXT;
 
        uint32_t _version { 0x0401 };
        HWND _hwnd { 0 };
        HDC _hdc { 0 };
        HGLRC _hglrc { 0 };
#endif
        QOpenGLContext* _qglContext { nullptr };
   
    private:
        Context(const Context& other);
        void qtCreate(QOpenGLContext* shareContext);
#ifdef Q_OS_WIN
        void createWrapperContext();
#endif
 
    public:
        static bool enableDebugLogger();
        static void debugMessageHandler(const QOpenGLDebugMessage &debugMessage);
        static void setupDebugLogging(QOpenGLContext* context);
        
        Context();
        Context(QWindow* window);
        void release();
        virtual ~Context();
 
        QWindow* getWindow() const { return _window; }
        void clear();
        void setWindow(QWindow* window);
        bool makeCurrent();
        static void makeCurrent(QOpenGLContext* context, QSurface* surface);
        void swapBuffers();
        void doneCurrent();
        virtual void create(QOpenGLContext* shareContext = nullptr);
        QOpenGLContext* qglContext() const { return _qglContext; }
        void moveToThread(QThread* thread);
 
        static size_t evalSurfaceMemoryUsage(uint32_t width, uint32_t height, uint32_t pixelSize);
        static size_t getSwapchainMemoryUsage();
        static void updateSwapchainMemoryUsage(size_t prevSize, size_t newSize);
        
     private:
        static std::atomic<size_t> _totalSwapchainMemoryUsage;
 
        size_t _swapchainMemoryUsage { 0 };
        size_t _swapchainPixelSize { 0 };
        void updateSwapchainMemoryCounter();
    };
 
    class OffscreenContext : public Context {
        using Parent = Context;
    public:
        virtual ~OffscreenContext();
        void create(QOpenGLContext* shareContext = nullptr) override;
    };
 
}
 
#endif // hifi_gpu_GPUConfig_h