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#include "qcocoaglcontext.h"
#include "qcocoawindow.h"
#include "qcocoaautoreleasepool.h"
#include <qdebug.h>
#include <QtCore/private/qcore_mac_p.h>
#include <QtPlatformSupport/private/cglconvenience_p.h>

#import <Cocoa/Cocoa.h>

QCocoaGLContext::QCocoaGLContext(const QSurfaceFormat &format, QPlatformOpenGLContext *share)
    : m_format(format)
{
    QCocoaAutoReleasePool pool; // For the SG Canvas render thread

    NSOpenGLPixelFormat *pixelFormat = static_cast <NSOpenGLPixelFormat *>(qcgl_createNSOpenGLPixelFormat(format));
    m_shareContext = share ? static_cast<QCocoaGLContext *>(share)->nsOpenGLContext() : nil;

    m_context = [NSOpenGLContext alloc];
    [m_context initWithFormat:pixelFormat shareContext:m_shareContext];

    if (!m_context && m_shareContext) {
        // try without shared context
        m_shareContext = nil;
        [m_context initWithFormat:pixelFormat shareContext:nil];
    }

    [pixelFormat release];

    const GLint interval = 1;
    [m_context setValues:&interval forParameter:NSOpenGLCPSwapInterval];

}

QCocoaGLContext::~QCocoaGLContext()
{
    [m_context release];
}

// Match up with createNSOpenGLPixelFormat!
QSurfaceFormat QCocoaGLContext::format() const
{
    return m_format;
}

void QCocoaGLContext::swapBuffers(QPlatformSurface *surface)
{
    QWindow *window = static_cast<QCocoaWindow *>(surface)->window();
    setActiveWindow(window);

    [m_context flushBuffer];
}

bool QCocoaGLContext::makeCurrent(QPlatformSurface *surface)
{
    Q_ASSERT(surface->surface()->surfaceType() == QSurface::OpenGLSurface);

    QCocoaAutoReleasePool pool;

    QWindow *window = static_cast<QCocoaWindow *>(surface)->window();
    setActiveWindow(window);

    [m_context makeCurrentContext];
    update();
    return true;
}

void QCocoaGLContext::setActiveWindow(QWindow *window)
{
    if (window == m_currentWindow.data())
        return;

    if (m_currentWindow && m_currentWindow.data()->handle())
        static_cast<QCocoaWindow *>(m_currentWindow.data()->handle())->setCurrentContext(0);

    Q_ASSERT(window->handle());

    m_currentWindow = window;

    QCocoaWindow *cocoaWindow = static_cast<QCocoaWindow *>(window->handle());
    cocoaWindow->setCurrentContext(this);

    [(QNSView *) cocoaWindow->contentView() setQCocoaGLContext:this];

    // Enable high-dpi OpenGL for retina displays. Enabling has the side
    // effect that Cooca will start calling glViewport(0, 0, width, height),
    // overriding any glViewport calls in application code. This is usually not a
    // problem, except if the applcation wants to have a "custom" viewport.
    // (like the hellogl example)
#if MAC_OS_X_VERSION_MAX_ALLOWED >= MAC_OS_X_VERSION_10_7
    if (QSysInfo::MacintoshVersion >= QSysInfo::MV_10_7) {
        if (cocoaWindow->devicePixelRatio() > 1)
            [cocoaWindow->contentView() setWantsBestResolutionOpenGLSurface:YES];
    }
#endif
}

void QCocoaGLContext::doneCurrent()
{
    if (m_currentWindow && m_currentWindow.data()->handle())
        static_cast<QCocoaWindow *>(m_currentWindow.data()->handle())->setCurrentContext(0);

    m_currentWindow.clear();

    [NSOpenGLContext clearCurrentContext];
}

void (*QCocoaGLContext::getProcAddress(const QByteArray &procName))()
{
    return qcgl_getProcAddress(procName);
}

void QCocoaGLContext::update()
{
    [m_context update];
}

NSOpenGLPixelFormat *QCocoaGLContext::createNSOpenGLPixelFormat(const QSurfaceFormat &format)
{
    return static_cast<NSOpenGLPixelFormat *>(qcgl_createNSOpenGLPixelFormat(format));
}

NSOpenGLContext *QCocoaGLContext::nsOpenGLContext() const
{
    return m_context;
}

bool QCocoaGLContext::isValid() const
{
    return m_context != nil;
}

bool QCocoaGLContext::isSharing() const
{
    return m_shareContext != nil;
}