/****************************************************************************

**

** Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies).

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** Contact: Nokia Corporation (qt-info@nokia.com)

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** This file is part of the QtOpenVG module of the Qt Toolkit.

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** contained in the Technology Preview License Agreement accompanying

** this package.

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** Foundation and appearing in the file LICENSE.LGPL included in the

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****************************************************************************/

#include "qwindowsurface_vgegl_p.h"

#include "qpaintengine_vg_p.h"

#include "qpixmapdata_vg_p.h"

#include "qvgimagepool_p.h"

#include "qvg_p.h"

#if !defined(QT_NO_EGL)

QT_BEGIN_NAMESPACE

// Turn off "direct to window" rendering if EGL cannot support it.

#if !defined(EGL_RENDER_BUFFER) || !defined(EGL_SINGLE_BUFFER)

#if defined(QVG_DIRECT_TO_WINDOW)

#undef QVG_DIRECT_TO_WINDOW

#endif

#endif

// Determine if preserved window contents should be used.

#if !defined(EGL_SWAP_BEHAVIOR) || !defined(EGL_BUFFER_PRESERVED)

#if !defined(QVG_NO_PRESERVED_SWAP)

#define QVG_NO_PRESERVED_SWAP 1

#endif

#endif

VGImageFormat qt_vg_config_to_vg_format(QEglContext *context)

{

    return qt_vg_image_to_vg_format

        (qt_vg_config_to_image_format(context));

}

QImage::Format qt_vg_config_to_image_format(QEglContext *context)

{

    EGLint red = 0;

    EGLint green = 0;

    EGLint blue = 0;

    EGLint alpha = 0;

    context->configAttrib(EGL_RED_SIZE, &red);

    context->configAttrib(EGL_GREEN_SIZE, &green);

    context->configAttrib(EGL_BLUE_SIZE, &blue);

    context->configAttrib(EGL_ALPHA_SIZE, &alpha);

    QImage::Format argbFormat;

#ifdef EGL_VG_ALPHA_FORMAT_PRE_BIT

    EGLint type = 0;

    context->configAttrib(EGL_SURFACE_TYPE, &type);

    if ((type & EGL_VG_ALPHA_FORMAT_PRE_BIT) != 0)

        argbFormat = QImage::Format_ARGB32_Premultiplied;

    else

        argbFormat = QImage::Format_ARGB32;

#else

    argbFormat = QImage::Format_ARGB32;

#endif

    if (red == 8 && green == 8 && blue == 8 && alpha == 8)

        return argbFormat;

    else if (red == 8 && green == 8 && blue == 8 && alpha == 0)

        return QImage::Format_RGB32;

    else if (red == 5 && green == 6 && blue == 5 && alpha == 0)

        return QImage::Format_RGB16;

    else if (red == 4 && green == 4 && blue == 4 && alpha == 4)

        return QImage::Format_ARGB4444_Premultiplied;

    else

        return argbFormat;       // XXX

}

#if !defined(QVG_NO_SINGLE_CONTEXT)

class QVGSharedContext

{

public:

    QVGSharedContext();

    ~QVGSharedContext();

    QEglContext *context;

    int refCount;

    int widgetRefCount;

    QVGPaintEngine *engine;

    EGLSurface surface;

    QVGPixmapData *firstPixmap;

};

QVGSharedContext::QVGSharedContext()

    : context(0)

    , refCount(0)

    , widgetRefCount(0)

    , engine(0)

    , surface(EGL_NO_SURFACE)

    , firstPixmap(0)

{

}

QVGSharedContext::~QVGSharedContext()

{

    // Don't accidentally destroy the QEglContext if the reference

    // count falls to zero while deleting the paint engine.

    ++refCount;

    if (context)

        context->makeCurrent(qt_vg_shared_surface());

    delete engine;

    if (context)

        context->doneCurrent();

    if (context && surface != EGL_NO_SURFACE)

        context->destroySurface(surface);

    delete context;

}

Q_GLOBAL_STATIC(QVGSharedContext, sharedContext);

QVGPaintEngine *qt_vg_create_paint_engine(void)

{

    QVGSharedContext *shared = sharedContext();

    if (!shared->engine)

        shared->engine = new QVGPaintEngine();

    return shared->engine;

}

void qt_vg_destroy_paint_engine(QVGPaintEngine *engine)

{

    Q_UNUSED(engine);

}

void qt_vg_register_pixmap(QVGPixmapData *pd)

{

    QVGSharedContext *shared = sharedContext();

    pd->next = shared->firstPixmap;

    pd->prev = 0;

    if (shared->firstPixmap)

        shared->firstPixmap->prev = pd;

    shared->firstPixmap = pd;

}

void qt_vg_unregister_pixmap(QVGPixmapData *pd)

{

    if (pd->next)

        pd->next->prev = pd->prev;

    if (pd->prev) {

        pd->prev->next = pd->next;

    } else {

        QVGSharedContext *shared = sharedContext();

        if (shared)

           shared->firstPixmap = pd->next;

    }

}

#else

QVGPaintEngine *qt_vg_create_paint_engine(void)

{

    return new QVGPaintEngine();

}

void qt_vg_destroy_paint_engine(QVGPaintEngine *engine)

{

    delete engine;

}

void qt_vg_register_pixmap(QVGPixmapData *pd)

{

    Q_UNUSED(pd);

}

void qt_vg_unregister_pixmap(QVGPixmapData *pd)

{

    Q_UNUSED(pd);

}

#endif

#ifdef EGL_VG_ALPHA_FORMAT_PRE_BIT

static bool isPremultipliedContext(const QEglContext *context)

{

    EGLint value = 0;

    if (context->configAttrib(EGL_SURFACE_TYPE, &value))

        return (value & EGL_VG_ALPHA_FORMAT_PRE_BIT) != 0;

    else

        return false;

}

#endif

static QEglContext *createContext(QPaintDevice *device)

{

    QEglContext *context;

    // Create the context object and open the display.

    context = new QEglContext();

    context->setApi(QEgl::OpenVG);

    // Set the swap interval for the display.

    QByteArray interval = qgetenv("QT_VG_SWAP_INTERVAL");

    if (!interval.isEmpty())

        eglSwapInterval(QEglContext::display(), interval.toInt());

    else

        eglSwapInterval(QEglContext::display(), 1);

#ifdef EGL_RENDERABLE_TYPE

    // Has the user specified an explicit EGL configuration to use?

    QByteArray configId = qgetenv("QT_VG_EGL_CONFIG");

    if (!configId.isEmpty()) {

        EGLint cfgId = configId.toInt();

        EGLint properties[] = {

            EGL_CONFIG_ID, cfgId,

            EGL_NONE

        };

        EGLint matching = 0;

        EGLConfig cfg;

        if (eglChooseConfig

                    (QEglContext::display(), properties, &cfg, 1, &matching) &&

                matching > 0) {

            // Check that the selected configuration actually supports OpenVG

            // and then create the context with it.

            EGLint id = 0;

            EGLint type = 0;

            eglGetConfigAttrib

                (QEglContext::display(), cfg, EGL_CONFIG_ID, &id);

            eglGetConfigAttrib

                (QEglContext::display(), cfg, EGL_RENDERABLE_TYPE, &type);

            if (cfgId == id && (type & EGL_OPENVG_BIT) != 0) {

                context->setConfig(cfg);

                if (!context->createContext()) {

                    delete context;

                    return 0;

                }

                return context;

            } else {

                qWarning("QT_VG_EGL_CONFIG: %d is not a valid OpenVG configuration", int(cfgId));

            }

        }

    }

#endif

    // Choose an appropriate configuration for rendering into the device.

    QEglProperties configProps;

    configProps.setPaintDeviceFormat(device);

    int redSize = configProps.value(EGL_RED_SIZE);

    if (redSize == EGL_DONT_CARE || redSize == 0)

        configProps.setPixelFormat(QImage::Format_ARGB32);  // XXX

#ifndef QVG_SCISSOR_CLIP

    // If we are using the mask to clip, then explicitly request a mask.

    configProps.setValue(EGL_ALPHA_MASK_SIZE, 1);

#endif

#ifdef EGL_VG_ALPHA_FORMAT_PRE_BIT

    configProps.setValue(EGL_SURFACE_TYPE, EGL_WINDOW_BIT |

                         EGL_VG_ALPHA_FORMAT_PRE_BIT);

    configProps.setRenderableType(QEgl::OpenVG);

    if (!context->chooseConfig(configProps)) {

        // Try again without the "pre" bit.

        configProps.setValue(EGL_SURFACE_TYPE, EGL_WINDOW_BIT);

        if (!context->chooseConfig(configProps)) {

            delete context;

            return 0;

        }

    }

#else

    configProps.setValue(EGL_SURFACE_TYPE, EGL_WINDOW_BIT);

    configProps.setRenderableType(QEgl::OpenVG);

    if (!context->chooseConfig(configProps)) {

        delete context;

        return 0;

    }

#endif

    // Construct a new EGL context for the selected configuration.

    if (!context->createContext()) {

        delete context;

        return 0;

    }

    return context;

}

#if !defined(QVG_NO_SINGLE_CONTEXT)

QEglContext *qt_vg_create_context(QPaintDevice *device, int devType)

{

    QVGSharedContext *shared = sharedContext();

    if (devType == QInternal::Widget)

        ++(shared->widgetRefCount);

    if (shared->context) {

        ++(shared->refCount);

        return shared->context;

    } else {

        shared->context = createContext(device);

        shared->refCount = 1;

        return shared->context;

    }

}

static void qt_vg_destroy_shared_context(QVGSharedContext *shared)

{

    shared->context->makeCurrent(qt_vg_shared_surface());

    delete shared->engine;

    shared->engine = 0;

    shared->context->doneCurrent();

    if (shared->surface != EGL_NO_SURFACE) {

        eglDestroySurface(QEglContext::display(), shared->surface);

        shared->surface = EGL_NO_SURFACE;

    }

    delete shared->context;

    shared->context = 0;

}

void qt_vg_hibernate_pixmaps(QVGSharedContext *shared)

{

    // Artificially increase the reference count to prevent the

    // context from being destroyed until after we have finished

    // the hibernation process.

    ++(shared->refCount);

    // We need a context current to hibernate the VGImage objects.

    shared->context->makeCurrent(qt_vg_shared_surface());

    // Scan all QVGPixmapData objects in the system and hibernate them.

    QVGPixmapData *pd = shared->firstPixmap;

    while (pd != 0) {

        pd->hibernate();

        pd = pd->next;

    }

    // Hibernate any remaining VGImage's in the image pool.

    QVGImagePool::instance()->hibernate();

    // Don't need the current context any more.

    shared->context->lazyDoneCurrent();

    // Decrease the reference count and destroy the context if necessary.

    if (--(shared->refCount) <= 0)

        qt_vg_destroy_shared_context(shared);

}

void qt_vg_destroy_context(QEglContext *context, int devType)

{

    QVGSharedContext *shared = sharedContext();

    if (shared->context != context) {

        // This is not the shared context.  Shouldn't happen!

        delete context;

        return;

    }

    if (devType == QInternal::Widget)

        --(shared->widgetRefCount);

    if (--(shared->refCount) <= 0) {

        qt_vg_destroy_shared_context(shared);

    } else if (shared->widgetRefCount <= 0 && devType == QInternal::Widget) {

        // All of the widget window surfaces have been destroyed

        // but we still have VG pixmaps active.  Ask them to hibernate

        // to free up GPU resources until a widget is shown again.

        // This may eventually cause the EGLContext to be destroyed

        // because nothing in the system needs a context, which will

        // free up even more GPU resources.

        qt_vg_hibernate_pixmaps(shared);

    }

}

EGLSurface qt_vg_shared_surface(void)

{

    QVGSharedContext *shared = sharedContext();

    if (shared->surface == EGL_NO_SURFACE) {

        EGLint attribs[7];

        attribs[0] = EGL_WIDTH;

        attribs[1] = 16;

        attribs[2] = EGL_HEIGHT;

        attribs[3] = 16;

#ifdef EGL_VG_ALPHA_FORMAT_PRE_BIT

        if (isPremultipliedContext(shared->context)) {

            attribs[4] = EGL_VG_ALPHA_FORMAT;

            attribs[5] = EGL_VG_ALPHA_FORMAT_PRE;

            attribs[6] = EGL_NONE;

        } else

#endif

        {

            attribs[4] = EGL_NONE;

        }

        shared->surface = eglCreatePbufferSurface

            (QEglContext::display(), shared->context->config(), attribs);

    }

    return shared->surface;

}

#else

QEglContext *qt_vg_create_context(QPaintDevice *device, int devType)

{

    Q_UNUSED(devType);

    return createContext(device);

}

void qt_vg_destroy_context(QEglContext *context, int devType)

{

    Q_UNUSED(devType);

    delete context;

}

EGLSurface qt_vg_shared_surface(void)

{

    return EGL_NO_SURFACE;

}

#endif

QVGEGLWindowSurfacePrivate::QVGEGLWindowSurfacePrivate(QWindowSurface *win)

{

    winSurface = win;

    engine = 0;

}

QVGEGLWindowSurfacePrivate::~QVGEGLWindowSurfacePrivate()

{

    // Destroy the paint engine if it hasn't been destroyed already.

    destroyPaintEngine();

}

QVGPaintEngine *QVGEGLWindowSurfacePrivate::paintEngine()

{

    if (!engine)

        engine = qt_vg_create_paint_engine();

    return engine;

}

VGImage QVGEGLWindowSurfacePrivate::surfaceImage() const

{

    return VG_INVALID_HANDLE;

}

void QVGEGLWindowSurfacePrivate::destroyPaintEngine()

{

    if (engine) {

        qt_vg_destroy_paint_engine(engine);

        engine = 0;

    }

}

QSize QVGEGLWindowSurfacePrivate::windowSurfaceSize(QWidget *widget) const

{

    Q_UNUSED(widget);

    QRect rect = winSurface->geometry();

    QSize newSize = rect.size();

#if defined(Q_WS_QWS)

    // Account for the widget mask, if any.

    if (widget && !widget->mask().isEmpty()) {

        const QRegion region = widget->mask()

                               & rect.translated(-widget->geometry().topLeft());

        newSize = region.boundingRect().size();

    }

#endif

    return newSize;

}

#if defined(QVG_VGIMAGE_BACKBUFFERS)

QVGEGLWindowSurfaceVGImage::QVGEGLWindowSurfaceVGImage(QWindowSurface *win)

    : QVGEGLWindowSurfacePrivate(win)

    , context(0)

    , backBuffer(VG_INVALID_HANDLE)

    , backBufferSurface(EGL_NO_SURFACE)

    , recreateBackBuffer(false)

    , isPaintingActive(false)

    , windowSurface(EGL_NO_SURFACE)

{

}

QVGEGLWindowSurfaceVGImage::~QVGEGLWindowSurfaceVGImage()

{

    destroyPaintEngine();

    if (context) {

        if (backBufferSurface != EGL_NO_SURFACE) {

            // We need a current context to be able to destroy the image.

            // We use the shared surface because the native window handle

            // associated with "windowSurface" may have been destroyed already.

            context->makeCurrent(qt_vg_shared_surface());

            context->destroySurface(backBufferSurface);

            vgDestroyImage(backBuffer);