qplatformglcontext_qpa.cpp

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#include "qplatformglcontext_qpa.h"

#include <QtCore/QThreadStorage>
#include <QtCore/QThread>

#include <QDebug>

class QPlatformGLThreadContext
{
public:
    ~QPlatformGLThreadContext() {
        if (context)
            context->doneCurrent();
    }
    QPlatformGLContext *context;
};

static QThreadStorage<QPlatformGLThreadContext *> qplatformgl_context_storage;

class QPlatformGLContextPrivate
{
public:
    QPlatformGLContextPrivate()
        :qGLContextHandle(0)
    {
    }

    virtual ~QPlatformGLContextPrivate()
    {
        //do not delete the QGLContext handle here as it is deleted in
        //QWidgetPrivate::deleteTLSysExtra()
    }
    void *qGLContextHandle;
    void (*qGLContextDeleteFunction)(void *handle);
    static QPlatformGLContext *staticSharedContext;

    static void setCurrentContext(QPlatformGLContext *context);
};

QPlatformGLContext *QPlatformGLContextPrivate::staticSharedContext = 0;

void QPlatformGLContextPrivate::setCurrentContext(QPlatformGLContext *context)
{
    QPlatformGLThreadContext *threadContext = qplatformgl_context_storage.localData();
    if (!threadContext) {
        if (!QThread::currentThread()) {
            qWarning("No QTLS available. currentContext wont work");
            return;
        }
        threadContext = new QPlatformGLThreadContext;
        qplatformgl_context_storage.setLocalData(threadContext);
    }
    threadContext->context = context;
}

const QPlatformGLContext* QPlatformGLContext::currentContext()
{
    QPlatformGLThreadContext *threadContext = qplatformgl_context_storage.localData();
    if(threadContext) {
        return threadContext->context;
    }
    return 0;
}

QPlatformGLContext::QPlatformGLContext()
    :d_ptr(new QPlatformGLContextPrivate())
{
}

QPlatformGLContext::~QPlatformGLContext()
{
    if (QPlatformGLContext::currentContext() == this) {
        doneCurrent();
    }

}

void QPlatformGLContext::makeCurrent()
{
    QPlatformGLContextPrivate::setCurrentContext(this);
}

void QPlatformGLContext::doneCurrent()
{
    QPlatformGLContextPrivate::setCurrentContext(0);
}

/*
  internal: Needs to have a pointer to qGLContext. But since this is in QtGui we cant
  have any type information.
*/
void *QPlatformGLContext::qGLContextHandle() const
{
    Q_D(const QPlatformGLContext);
    return d->qGLContextHandle;
}

void QPlatformGLContext::setQGLContextHandle(void *handle,void (*qGLContextDeleteFunction)(void *))
{
    Q_D(QPlatformGLContext);
    d->qGLContextHandle = handle;
    d->qGLContextDeleteFunction = qGLContextDeleteFunction;
}

void QPlatformGLContext::deleteQGLContext()
{
    Q_D(QPlatformGLContext);
    if (d->qGLContextDeleteFunction && d->qGLContextHandle) {
        d->qGLContextDeleteFunction(d->qGLContextHandle);
        d->qGLContextDeleteFunction = 0;
        d->qGLContextHandle = 0;
    }
}