-
Iikka Eklund authored
Change copyrights and license headers from Nokia to Digia Change-Id: Ie7f5d49ed8235d7a7845ab68f99ad1c220e64d5c Reviewed-by:Lars Knoll <lars.knoll@digia.com>
46010aa7
/******************************************************************************** Copyright (C) 2012 Digia Plc and/or its subsidiary(-ies).** Contact: http://www.qt-project.org/legal**** This file is part of the QtQml module of the Qt Toolkit.**** $QT_BEGIN_LICENSE:LGPL$** Commercial License Usage** Licensees holding valid commercial Qt licenses may use this file in** accordance with the commercial license agreement provided with the** Software or, alternatively, in accordance with the terms contained in** a written agreement between you and Digia. For licensing terms and** conditions see http://qt.digia.com/licensing. For further information** use the contact form at http://qt.digia.com/contact-us.**** GNU Lesser General Public License Usage** Alternatively, this file may be used under the terms of the GNU Lesser** General Public License version 2.1 as published by the Free Software** Foundation and appearing in the file LICENSE.LGPL included in the** packaging of this file. Please review the following information to** ensure the GNU Lesser General Public License version 2.1 requirements** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.**** In addition, as a special exception, Digia gives you certain additional** rights. These rights are described in the Digia Qt LGPL Exception** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.**** GNU General Public License Usage** Alternatively, this file may be used under the terms of the GNU** General Public License version 3.0 as published by the Free Software** Foundation and appearing in the file LICENSE.GPL included in the** packaging of this file. Please review the following information to** ensure the GNU General Public License version 3.0 requirements will be** met: http://www.gnu.org/copyleft/gpl.html.****** $QT_END_LICENSE$******************************************************************************/#include <private/qsgadaptationlayer_p.h>#include "qquickcanvasitem_p.h"#include <private/qquickitem_p.h>#include <private/qquickcanvascontext_p.h>#include <private/qquickcontext2d_p.h>#include <qsgsimpletexturenode.h>#include <QtQuick/private/qquickpixmapcache_p.h>#include <qqmlinfo.h>#include <private/qqmlengine_p.h>#include <QtCore/QBuffer>QT_BEGIN_NAMESPACEQQuickCanvasPixmap::QQuickCanvasPixmap(const QImage& image, QQuickWindow *window) : m_pixmap(0) , m_image(image) , m_texture(0) , m_window(window){}QQuickCanvasPixmap::QQuickCanvasPixmap(QQuickPixmap *pixmap, QQuickWindow *window) : m_pixmap(pixmap) , m_texture(0) , m_window(window){7172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140
}
QQuickCanvasPixmap::~QQuickCanvasPixmap()
{
delete m_pixmap;
if (m_texture)
m_texture->deleteLater();
}
qreal QQuickCanvasPixmap::width() const
{
if (m_pixmap)
return m_pixmap->width();
return m_image.width();
}
qreal QQuickCanvasPixmap::height() const
{
if (m_pixmap)
return m_pixmap->height();
return m_image.height();
}
bool QQuickCanvasPixmap::isValid() const
{
if (m_pixmap)
return m_pixmap->isReady();
return !m_image.isNull();
}
QSGTexture *QQuickCanvasPixmap::texture()
{
if (!m_texture) {
if (m_pixmap) {
Q_ASSERT(m_pixmap->textureFactory());
m_texture = m_pixmap->textureFactory()->createTexture(m_window);
} else {
m_texture = QQuickWindowPrivate::get(m_window)->context->createTexture(m_image);
}
}
return m_texture;
}
QImage QQuickCanvasPixmap::image()
{
if (m_image.isNull() && m_pixmap)
m_image = m_pixmap->image();
return m_image;
}
QHash<QQmlEngine *,QQuickContext2DRenderThread*> QQuickContext2DRenderThread::renderThreads;
QMutex QQuickContext2DRenderThread::renderThreadsMutex;
QQuickContext2DRenderThread::QQuickContext2DRenderThread(QQmlEngine *eng)
: QThread(eng), m_engine(eng), m_eventLoopQuitHack(0)
{
Q_ASSERT(eng);
m_eventLoopQuitHack = new QObject;
m_eventLoopQuitHack->moveToThread(this);
connect(m_eventLoopQuitHack, SIGNAL(destroyed(QObject*)), SLOT(quit()), Qt::DirectConnection);
start(QThread::IdlePriority);
}
QQuickContext2DRenderThread::~QQuickContext2DRenderThread()
{
renderThreadsMutex.lock();
renderThreads.remove(m_engine);
renderThreadsMutex.unlock();
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m_eventLoopQuitHack->deleteLater();
wait();
}
QQuickContext2DRenderThread *QQuickContext2DRenderThread::instance(QQmlEngine *engine)
{
QQuickContext2DRenderThread *thread = 0;
renderThreadsMutex.lock();
if (renderThreads.contains(engine))
thread = renderThreads.value(engine);
else {
thread = new QQuickContext2DRenderThread(engine);
renderThreads.insert(engine, thread);
}
renderThreadsMutex.unlock();
return thread;
}
class QQuickCanvasItemPrivate : public QQuickItemPrivate
{
public:
QQuickCanvasItemPrivate();
~QQuickCanvasItemPrivate();
QQuickCanvasContext *context;
QSizeF canvasSize;
QSize tileSize;
QRectF canvasWindow;
QRectF dirtyRect;
uint hasCanvasSize :1;
uint hasTileSize :1;
uint hasCanvasWindow :1;
uint available :1;
uint contextInitialized :1;
QQuickCanvasItem::RenderTarget renderTarget;
QQuickCanvasItem::RenderStrategy renderStrategy;
QString contextType;
QHash<QUrl, QQmlRefPointer<QQuickCanvasPixmap> > pixmaps;
QUrl baseUrl;
QMap<int, v8::Persistent<v8::Function> > animationCallbacks;
};
QQuickCanvasItemPrivate::QQuickCanvasItemPrivate()
: QQuickItemPrivate()
, context(0)
, canvasSize(1, 1)
, tileSize(1, 1)
, hasCanvasSize(false)
, hasTileSize(false)
, hasCanvasWindow(false)
, available(false)
, contextInitialized(false)
, renderTarget(QQuickCanvasItem::FramebufferObject)
, renderStrategy(QQuickCanvasItem::Cooperative)
{
}
QQuickCanvasItemPrivate::~QQuickCanvasItemPrivate()
{
pixmaps.clear();
}
/*!
\qmltype Canvas
\instantiates QQuickCanvasItem
\inqmlmodule QtQuick 2
\since QtQuick 2.0
\inherits Item
\ingroup qtquick-canvas
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\ingroup qtquick-visual
\brief Provides a 2D canvas item enabling drawing via JavaScript
The Canvas item allows drawing of straight and curved lines, simple and
complex shapes, graphs, and referenced graphic images. It can also add
text, colors, shadows, gradients, and patterns, and do low level pixel
operations. The Canvas output may be saved as an image file or serialized
to a URL.
To define a drawing area in the Canvas item set the \c width and \c height
properties. For example, the following code creates a Canvas item which
has a drawing area with a height of 100 pixels and width of 200 pixels:
\qml
import QtQuick 2.0
Canvas {
id: mycanvas
width: 100
height: 200
}
\endqml
Currently the Canvas item only supports the two-dimensional rendering context.
\section1 Threaded Rendering and Render Target
The Canvas item supports two render targets: \c Canvas.Image and
\c Canvas.FramebufferObject.
The \c Canvas.Image render target is a \a QImage object. This render
target supports background thread rendering, allowing complex or long
running painting to be executed without blocking the UI.
The Canvas.FramebufferObject render target utilizes OpenGL hardware
acceleration rather than rendering into system memory, which in many cases
results in faster rendering.
The default render target is Canvas.Image and the default renderStrategy is
Canvas.Threaded.
\section1 Tiled Canvas
The Canvas item supports tiled rendering by setting \l canvasSize, \l tileSize
and \l canvasWindow properties.
Tiling allows efficient display of a very large virtual canvas via a smaller
canvas window. The actual memory consumption is in relation to the canvas
window size. The painting code can draw within the virtual canvas without
handling coordinate system transformations.
The tiles overlapping with the canvas window may be cached eliminating the
need to redraw, which can lead to significantly improved performance in
some situations.
\section1 Pixel Operations
All HTML5 2D context pixel operations are supported. In order to ensure
improved pixel reading/writing performance the \a Canvas.Image render
target should be chosen. The \a Canvas.FramebufferObject render target
requires the pixel data to be exchanged between the system memory and the
graphic card, which is significantly more expensive. Rendering may also be
synchronized with the V-sync signal (to avoid
\l{en.wikipedia.org/wiki/Screen_tearing}{screen tearing}) which will further
impact pixel operations with \c Canvas.FrambufferObject render target.
\section1 Tips for Porting Existing HTML5 Canvas applications
Although the Canvas item is provides a HTML5 like API, HTML5 canvas
applications need to be modified to run in the Canvas item:
\list
\li Replace all DOM API calls with QML property bindings or Canvas item methods.
\li Replace all HTML event handlers with the MouseArea item.
\li Change setInterval/setTimeout function calls with the \l Timer item or
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the use of requestAnimationFrame().
\li Place painting code into the onPaint handler and trigger
painting by calling the markDirty() or requestPaint() methods.
\li To draw images, load them by calling the Canvas's loadImage() method and then request to paint
them in the onImageLoaded handler.
\endlist
\sa Context2D
*/
QQuickCanvasItem::QQuickCanvasItem(QQuickItem *parent)
: QQuickItem(*(new QQuickCanvasItemPrivate), parent)
{
setFlag(ItemHasContents);
}
QQuickCanvasItem::~QQuickCanvasItem()
{
Q_D(QQuickCanvasItem);
delete d->context;
}
/*!
\qmlproperty size QtQuick2::Canvas::available
Indicates when Canvas is able to provide a drawing context to operate on.
*/
bool QQuickCanvasItem::isAvailable() const
{
return d_func()->available;
}
/*!
\qmlproperty string QtQuick2::Canvas::contextType
The type of drawing context to use.
This property is set to the name of the active context type.
If set explicitly the canvas will attempt to create a context of the
named type after becoming available.
The type name is the same as used in the getContext() call, for the 2d
canvas the value will be "2d".
\sa getContext(), available
*/
QString QQuickCanvasItem::contextType() const
{
return d_func()->contextType;
}
void QQuickCanvasItem::setContextType(const QString &contextType)
{
Q_D(QQuickCanvasItem);
if (contextType.compare(d->contextType, Qt::CaseInsensitive) == 0)
return;
if (d->contextInitialized) {
qmlInfo(this) << "Canvas already initialized with a different context type";
return;
}
d->contextType = contextType;
if (d->available)
createContext(contextType);
351352353354355356357358359360361362363364365366367368369370371372373374375376377378379380381382383384385386387388389390391392393394395396397398399400401402403404405406407408409410411412413414415416417418419420
emit contextTypeChanged();
}
/*!
\qmlproperty object QtQuick2::Canvas::context
Holds the active drawing context.
If the canvas is ready and there has been a successful call to getContext()
or the contextType property has been set with a supported context type,
this property will contain the current drawing context, otherwise null.
*/
QQmlV8Handle QQuickCanvasItem::context() const
{
Q_D(const QQuickCanvasItem);
if (d->contextInitialized)
return QQmlV8Handle::fromHandle(d->context->v8value());
return QQmlV8Handle::fromHandle(v8::Null());
}
/*!
\qmlproperty size QtQuick2::Canvas::canvasSize
Holds the logical canvas size that the context paints on.
By default, the canvas size is the same size as the current canvas item
size.
By setting the canvasSize, tileSize and canvasWindow, the Canvas item can
act as a large virtual canvas with many separately rendered tile rectangles.
Only those tiles within the current canvas window are painted by the Canvas
render engine.
\sa tileSize, canvasWindow
*/
QSizeF QQuickCanvasItem::canvasSize() const
{
Q_D(const QQuickCanvasItem);
return d->canvasSize;
}
void QQuickCanvasItem::setCanvasSize(const QSizeF & size)
{
Q_D(QQuickCanvasItem);
if (d->canvasSize != size) {
d->hasCanvasSize = true;
d->canvasSize = size;
emit canvasSizeChanged();
if (d->contextInitialized)
polish();
}
}
/*!
\qmlproperty size QtQuick2::Canvas::tileSize
Holds the canvas rendering tile size.
The Canvas item enters tiled mode by setting canvasSize, tileSize and the
canvasWindow. This can improve rendering performance by rendering and
caching tiles instead of rendering the whole canvas every time.
Memory will be consumed only by those tiles within the current visible
region.
By default the tileSize is the same as the canvasSize.
\sa canvasSize, canvasWindow
*/
QSize QQuickCanvasItem::tileSize() const
421422423424425426427428429430431432433434435436437438439440441442443444445446447448449450451452453454455456457458459460461462463464465466467468469470471472473474475476477478479480481482483484485486487488489490
{
Q_D(const QQuickCanvasItem);
return d->tileSize;
}
void QQuickCanvasItem::setTileSize(const QSize & size)
{
Q_D(QQuickCanvasItem);
if (d->tileSize != size) {
d->hasTileSize = true;
d->tileSize = size;
emit tileSizeChanged();
if (d->contextInitialized)
polish();
}
}
/*!
\qmlproperty rect QtQuick2::Canvas::canvasWindow
Holds the current canvas visible window.
By default the canvasWindow size is the same as the Canvas item size with
the top-left point as (0, 0).
If the canvasSize is different to the Canvas item size, the Canvas item
can display different visible areas by changing the canvas windowSize
and/or position.
\sa canvasSize, tileSize
*/
QRectF QQuickCanvasItem::canvasWindow() const
{
Q_D(const QQuickCanvasItem);
return d->canvasWindow;
}
void QQuickCanvasItem::setCanvasWindow(const QRectF& rect)
{
Q_D(QQuickCanvasItem);
if (d->canvasWindow != rect) {
d->canvasWindow = rect;
d->hasCanvasWindow = true;
emit canvasWindowChanged();
if (d->contextInitialized)
polish();
}
}
/*!
\qmlproperty enumeration QtQuick2::Canvas::renderTarget
Holds the current canvas render target.
\list
\li Canvas.Image - render to an in memory image buffer.
\li Canvas.FramebufferObject - render to an OpenGL frame buffer
\endlist
This hint is supplied along with renderStrategy to the graphics context to
determine the method of rendering. A renderStrategy, renderTarget or a
combination may not be supported by a graphics context, in which case the
context will choose appropriate options and Canvas will signal the change
to the properties.
The default render target is \c Canvas.FramebufferObject.
*/
QQuickCanvasItem::RenderTarget QQuickCanvasItem::renderTarget() const
491492493494495496497498499500501502503504505506507508509510511512513514515516517518519520521522523524525526527528529530531532533534535536537538539540541542543544545546547548549550551552553554555556557558559560
{
Q_D(const QQuickCanvasItem);
return d->renderTarget;
}
void QQuickCanvasItem::setRenderTarget(QQuickCanvasItem::RenderTarget target)
{
Q_D(QQuickCanvasItem);
if (d->renderTarget != target) {
if (d->contextInitialized) {
qmlInfo(this) << "Canvas:renderTarget not changeble once context is active.";
return;
}
d->renderTarget = target;
emit renderTargetChanged();
}
}
/*!
\qmlproperty enumeration QtQuick2::Canvas::renderStrategy
Holds the current canvas rendering strategy.
\list
\li Canvas.Immediate - context will perform graphics commands immediately in the main UI thread.
\li Canvas.Threaded - context will defer graphics commands to a private rendering thread.
\li Canvas.Cooperative - context will defer graphics commands to the applications global render thread.
\endlist
This hint is supplied along with renderTarget to the graphics context to
determine the method of rendering. A renderStrategy, renderTarget or a
combination may not be supported by a graphics context, in which case the
context will choose appropriate options and Canvas will signal the change
to the properties.
Configuration or runtime tests may cause the QML Scene Graph to render in
the GUI thread. Selecting \c Canvas.Cooperative, does not guarantee
rendering will occur on a thread separate from the GUI thread.
The default value is \c Canvas.Cooperative.
\sa renderTarget
*/
QQuickCanvasItem::RenderStrategy QQuickCanvasItem::renderStrategy() const
{
return d_func()->renderStrategy;
}
void QQuickCanvasItem::setRenderStrategy(QQuickCanvasItem::RenderStrategy strategy)
{
Q_D(QQuickCanvasItem);
if (d->renderStrategy != strategy) {
if (d->contextInitialized) {
qmlInfo(this) << "Canvas:renderStrategy not changeable once context is active.";
return;
}
d->renderStrategy = strategy;
emit renderStrategyChanged();
}
}
QQuickCanvasContext* QQuickCanvasItem::rawContext() const
{
return d_func()->context;
}
bool QQuickCanvasItem::isPaintConnected()
{
IS_SIGNAL_CONNECTED(this, QQuickCanvasItem, paint, (const QRect &));
561562563564565566567568569570571572573574575576577578579580581582583584585586587588589590591592593594595596597598599600601602603604605606607608609610611612613614615616617618619620621622623624625626627628629630
}
void QQuickCanvasItem::sceneGraphInitialized()
{
Q_D(QQuickCanvasItem);
d->available = true;
connect(this, SIGNAL(visibleChanged()), SLOT(checkAnimationCallbacks()));
QMetaObject::invokeMethod(this, "availableChanged", Qt::QueuedConnection);
if (!d->contextType.isNull())
QMetaObject::invokeMethod(this, "delayedCreate", Qt::QueuedConnection);
else if (isPaintConnected())
QMetaObject::invokeMethod(this, "requestPaint", Qt::QueuedConnection);
}
void QQuickCanvasItem::geometryChanged(const QRectF &newGeometry, const QRectF &oldGeometry)
{
Q_D(QQuickCanvasItem);
QQuickItem::geometryChanged(newGeometry, oldGeometry);
QSizeF newSize = newGeometry.size();
if (!d->hasCanvasSize && d->canvasSize != newSize) {
d->canvasSize = newSize;
emit canvasSizeChanged();
}
if (!d->hasTileSize && d->tileSize != newSize) {
d->tileSize = newSize.toSize();
emit tileSizeChanged();
}
const QRectF rect = QRectF(QPointF(0, 0), newSize);
if (!d->hasCanvasWindow && d->canvasWindow != rect) {
d->canvasWindow = rect;
emit canvasWindowChanged();
}
if (d->available)
requestPaint();
}
void QQuickCanvasItem::releaseResources()
{
Q_D(QQuickCanvasItem);
if (d->context) {
delete d->context;
d->context = 0;
}
}
void QQuickCanvasItem::componentComplete()
{
QQuickItem::componentComplete();
Q_D(QQuickCanvasItem);
d->baseUrl = qmlEngine(this)->contextForObject(this)->baseUrl();
}
void QQuickCanvasItem::itemChange(QQuickItem::ItemChange change, const QQuickItem::ItemChangeData &value)
{
QQuickItem::itemChange(change, value);
if (change != QQuickItem::ItemSceneChange)
return;
Q_D(QQuickCanvasItem);
if (d->available)
631632633634635636637638639640641642643644645646647648649650651652653654655656657658659660661662663664665666667668669670671672673674675676677678679680681682683684685686687688689690691692693694695696697698699700
return;
if (value.window== 0)
return;
d->window = value.window;
if (d->window->openglContext() != 0) // available context == initialized
sceneGraphInitialized();
else
connect(d->window, SIGNAL(sceneGraphInitialized()), SLOT(sceneGraphInitialized()));
}
void QQuickCanvasItem::updatePolish()
{
QQuickItem::updatePolish();
Q_D(QQuickCanvasItem);
if (d->contextInitialized)
d->context->prepare(d->canvasSize.toSize(), d->tileSize, d->canvasWindow.toRect(), d->dirtyRect.toRect(), d->smooth, d->antialiasing);
if (d->animationCallbacks.size() > 0 && isVisible()) {
QMap<int, v8::Persistent<v8::Function> > animationCallbacks = d->animationCallbacks;
d->animationCallbacks.clear();
foreach (int key, animationCallbacks.keys()) {
v8::HandleScope handle_scope;
v8::Handle<v8::Object> self = QQmlEnginePrivate::getV8Engine(qmlEngine(this))->newQObject(this).As<v8::Object>();
v8::Handle<v8::Value> args[] = { v8::Uint32::New(QDateTime::currentDateTimeUtc().toTime_t()) };
v8::Persistent<v8::Function> f = animationCallbacks.value(key);
f->Call(self, 1, args);
f.Dispose();
}
}
else {
if (d->dirtyRect.isValid()) {
if (d->hasTileSize && d->hasCanvasWindow)
emit paint(tiledRect(d->canvasWindow.intersected(d->dirtyRect.toAlignedRect()), d->tileSize));
else
emit paint(d->dirtyRect.toRect());
d->dirtyRect = QRectF();
}
}
if (d->contextInitialized) {
if (d->renderStrategy == QQuickCanvasItem::Cooperative)
update();
else
d->context->flush();
}
}
QSGNode *QQuickCanvasItem::updatePaintNode(QSGNode *oldNode, UpdatePaintNodeData *)
{
Q_D(QQuickCanvasItem);
if (!d->contextInitialized)
return 0;
QSGSimpleTextureNode *node = static_cast<QSGSimpleTextureNode*>(oldNode);
if (!node)
node = new QSGSimpleTextureNode;
if (d->smooth)
node->setFiltering(QSGTexture::Linear);
else
node->setFiltering(QSGTexture::Nearest);
if (d->renderStrategy == QQuickCanvasItem::Cooperative)
d->context->flush();
701702703704705706707708709710711712713714715716717718719720721722723724725726727728729730731732733734735736737738739740741742743744745746747748749750751752753754755756757758759760761762763764765766767768769770
node->setTexture(d->context->texture());
node->setRect(QRectF(QPoint(0, 0), d->canvasWindow.size()));
return node;
}
/*!
\qmlmethod object QtQuick2::Canvas::getContext(string contextId, any... args)
Returns a drawing context or null if no context available.
The \a contextId parameter names the required context. The Canvas item
will return a context that implements the required drawing mode. After the
first call to getContext any subsequent call to getContext with the same
contextId will return the same context object.
If the context type is not supported or the canvas has previously been
requested to provide a different and incompatible context type, null will
be returned.
Canvas only supports a 2d context.
*/
void QQuickCanvasItem::getContext(QQmlV8Function *args)
{
Q_D(QQuickCanvasItem);
if (args->Length() < 1 || !(*args)[0]->IsString()) {
qmlInfo(this) << "getContext should be called with a string naming the required context type";
args->returnValue(v8::Null());
return;
}
if (!d->available) {
qmlInfo(this) << "Unable to use getContext() at this time, please wait for available: true";
args->returnValue(v8::Null());
return;
}
QString contextId = QString::fromUtf16(*v8::String::Value((*args)[0]));
if (d->context != 0) {
if (d->context->contextNames().contains(contextId, Qt::CaseInsensitive)) {
args->returnValue(d->context->v8value());
return;
}
qmlInfo(this) << "Canvas already initialized with a different context type";
args->returnValue(v8::Null());
return;
}
if (createContext(contextId))
args->returnValue(d->context->v8value());
else
args->returnValue(v8::Null());
}
/*!
\qmlmethod long QtQuick2::Canvas::requestAnimationFrame(callback)
This function schedules callback to be invoked before composing the QtQuick
scene.
*/
void QQuickCanvasItem::requestAnimationFrame(QQmlV8Function *args)
{
if (args->Length() < 1 || !(*args)[0]->IsFunction()) {
qmlInfo(this) << "requestAnimationFrame should be called with an animation callback function";
args->returnValue(v8::Null());
771772773774775776777778779780781782783784785786787788789790791792793794795796797798799800801802803804805806807808809810811812813814815816817818819820821822823824825826827828829830831832833834835836837838839840
return;
}
Q_D(QQuickCanvasItem);
static int id = 0;
d->animationCallbacks.insert(++id, v8::Persistent<v8::Function>::New(((*args)[0]).As<v8::Function>()));
if (isVisible())
polish();
args->returnValue(v8::Int32::New(id));
}
/*!
\qmlmethod QtQuick2::Canvas::cancelRequestAnimationFrame(long handle)
This function will cancel the animation callback referenced by \a handle.
*/
void QQuickCanvasItem::cancelRequestAnimationFrame(QQmlV8Function *args)
{
if (args->Length() < 1 || !(*args)[0]->IsInt32()) {
qmlInfo(this) << "cancelRequestAnimationFrame should be called with an animation callback id";
args->returnValue(v8::Null());
return;
}
d_func()->animationCallbacks.remove((*args)[0]->Int32Value());
}
/*!
\qmlmethod QtQuick2::Canvas::requestPaint()
Request the entire visible region be re-drawn.
\sa markDirty()
*/
void QQuickCanvasItem::requestPaint()
{
markDirty(d_func()->canvasWindow);
}
/*!
\qmlmethod QtQuick2::Canvas::markDirty(rect area)
Mark the given \a area as dirty, so that when this area is visible the
canvas renderer will redraw it. This will trigger the onPaint signal
handler function.
\sa paint, requestPaint()
*/
void QQuickCanvasItem::markDirty(const QRectF& rect)
{
Q_D(QQuickCanvasItem);
if (!d->available)
return;
d->dirtyRect |= rect;
polish();
}
void QQuickCanvasItem::checkAnimationCallbacks()
{
if (d_func()->animationCallbacks.size() > 0 && isVisible())
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polish();
}
/*!
\qmlmethod bool QtQuick2::Canvas::save(string filename)
Save the current canvas content into an image file \a filename.
The saved image format is automatically decided by the \a filename's
suffix.
Note: calling this method will force painting the whole canvas, not just the
current canvas visible window.
\sa canvasWindow, canvasSize, toDataURL()
*/
bool QQuickCanvasItem::save(const QString &filename) const
{
Q_D(const QQuickCanvasItem);
QUrl url = d->baseUrl.resolved(QUrl::fromLocalFile(filename));
return toImage().save(url.toLocalFile());
}
QQmlRefPointer<QQuickCanvasPixmap> QQuickCanvasItem::loadedPixmap(const QUrl& url)
{
Q_D(QQuickCanvasItem);
QUrl fullPathUrl = d->baseUrl.resolved(url);
if (!d->pixmaps.contains(fullPathUrl)) {
loadImage(url);
}
return d->pixmaps.value(fullPathUrl);
}
/*!
\qmlsignal QtQuick2::Canvas::onImageLoaded()
This handler is called when an image has been loaded.
\sa loadImage()
*/
/*!
\qmlmethod QtQuick2::Canvas::loadImage(url image)
Loads the given \c image asynchronously.
When the image is ready, onImageLoaded will be emitted.
The loaded image can be unloaded by the unloadImage() method.
Note: Only loaded images can be painted on the Canvas item.
\sa unloadImage, onImageLoaded, isImageLoaded(),
Context2D::createImageData(), Context2D::drawImage()
*/
void QQuickCanvasItem::loadImage(const QUrl& url)
{
Q_D(QQuickCanvasItem);
QUrl fullPathUrl = d->baseUrl.resolved(url);
if (!d->pixmaps.contains(fullPathUrl)) {
QQuickPixmap* pix = new QQuickPixmap();
QQmlRefPointer<QQuickCanvasPixmap> canvasPix;
canvasPix.take(new QQuickCanvasPixmap(pix, d->window));
d->pixmaps.insert(fullPathUrl, canvasPix);
pix->load(qmlEngine(this)
, fullPathUrl
, QQuickPixmap::Cache | QQuickPixmap::Asynchronous);
if (pix->isLoading())
pix->connectFinished(this, SIGNAL(imageLoaded()));
}
}
/*!
\qmlmethod QtQuick2::Canvas::unloadImage(url image)
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Unloads the \c image.
Once an image is unloaded it cannot be painted by the canvas context
unless it is loaded again.
\sa loadImage(), onImageLoaded, isImageLoaded(),
Context2D::createImageData(), Context2D::drawImage
*/
void QQuickCanvasItem::unloadImage(const QUrl& url)
{
Q_D(QQuickCanvasItem);
d->pixmaps.remove(d->baseUrl.resolved(url));
}
/*!
\qmlmethod QtQuick2::Canvas::isImageError(url image)
Returns true if the \a image failed to load.
\sa loadImage()
*/
bool QQuickCanvasItem::isImageError(const QUrl& url) const
{
Q_D(const QQuickCanvasItem);
QUrl fullPathUrl = d->baseUrl.resolved(url);
return d->pixmaps.contains(fullPathUrl)
&& d->pixmaps.value(fullPathUrl)->pixmap()->isError();
}
/*!
\qmlmethod QtQuick2::Canvas::isImageLoading(url image)
Returns true if the \a image is currently loading.
\sa loadImage()
*/
bool QQuickCanvasItem::isImageLoading(const QUrl& url) const
{
Q_D(const QQuickCanvasItem);
QUrl fullPathUrl = d->baseUrl.resolved(url);
return d->pixmaps.contains(fullPathUrl)
&& d->pixmaps.value(fullPathUrl)->pixmap()->isLoading();
}
/*!
\qmlmethod QtQuick2::Canvas::isImageLoaded(url image)
Returns true if the \a image is successfully loaded and ready to use.
\sa loadImage()
*/
bool QQuickCanvasItem::isImageLoaded(const QUrl& url) const
{
Q_D(const QQuickCanvasItem);
QUrl fullPathUrl = d->baseUrl.resolved(url);
return d->pixmaps.contains(fullPathUrl)
&& d->pixmaps.value(fullPathUrl)->pixmap()->isReady();
}
QImage QQuickCanvasItem::toImage(const QRectF& rect) const
{
Q_D(const QQuickCanvasItem);
if (d->contextInitialized) {
if (rect.isEmpty())
return d->context->toImage(canvasWindow());
else
return d->context->toImage(rect);
}
return QImage();
}
/*!
\qmlmethod string QtQuick2::Canvas::toDataURL(string mimeType)
981982983984985986987988989990991992993994995996997998999100010011002100310041005100610071008100910101011101210131014101510161017101810191020102110221023102410251026102710281029103010311032103310341035103610371038103910401041104210431044104510461047104810491050
Returns a data URL for the image in the canvas.
The default \a mimeType is "image/png".
\sa save()
*/
QString QQuickCanvasItem::toDataURL(const QString& mimeType) const
{
QImage image = toImage();
if (!image.isNull()) {
QByteArray ba;
QBuffer buffer(&ba);
buffer.open(QIODevice::WriteOnly);
QString mime = mimeType.toLower();
QString type;
if (mime == QLatin1String("image/png")) {
type = QStringLiteral("PNG");
} else if (mime == QLatin1String("image/bmp"))
type = QStringLiteral("BMP");
else if (mime == QLatin1String("image/jpeg"))
type = QStringLiteral("JPEG");
else if (mime == QLatin1String("image/x-portable-pixmap"))
type = QStringLiteral("PPM");
else if (mime == QLatin1String("image/tiff"))
type = QStringLiteral("TIFF");
else if (mime == QLatin1String("image/xpm"))
type = QStringLiteral("XPM");
else
return QStringLiteral("data:,");
image.save(&buffer, type.toLatin1());
buffer.close();
QString dataUrl = QStringLiteral("data:%1;base64,%2");
return dataUrl.arg(mime).arg(QLatin1String(ba.toBase64().constData()));
}
return QStringLiteral("data:,");
}
void QQuickCanvasItem::delayedCreate()
{
Q_D(QQuickCanvasItem);
if (!d->contextInitialized && !d->contextType.isNull())
createContext(d->contextType);
requestPaint();
}
bool QQuickCanvasItem::createContext(const QString &contextType)
{
Q_D(QQuickCanvasItem);
if (contextType == QLatin1String("2d")) {
if (d->contextType.compare(QLatin1String("2d"), Qt::CaseInsensitive) != 0) {
d->contextType = QLatin1String("2d");
emit contextTypeChanged(); // XXX: can't be in setContextType()
}
initializeContext(new QQuickContext2D(this));
return true;
}
return false;
}
void QQuickCanvasItem::initializeContext(QQuickCanvasContext *context, const QVariantMap &args)
{
Q_D(QQuickCanvasItem);
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d->context = context;
d->context->init(this, args);
d->context->setV8Engine(QQmlEnginePrivate::getV8Engine(qmlEngine(this)));
d->contextInitialized = true;
connect(d->context, SIGNAL(textureChanged()), SLOT(update()));
connect(d->context, SIGNAL(textureChanged()), SIGNAL(painted()));
emit contextChanged();
}
QRect QQuickCanvasItem::tiledRect(const QRectF &window, const QSize &tileSize)
{
if (window.isEmpty())
return QRect();
const int tw = tileSize.width();
const int th = tileSize.height();
const int h1 = window.left() / tw;
const int v1 = window.top() / th;
const int htiles = ((window.right() - h1 * tw) + tw - 1)/tw;
const int vtiles = ((window.bottom() - v1 * th) + th - 1)/th;
return QRect(h1 * tw, v1 * th, htiles * tw, vtiles * th);
}
/*!
\qmlsignal QtQuick2::Canvas::onPaint(rect region)
This handler is called to render the \a region. If a context is active it
can be referenced from the context property.
This signal can be triggered markdirty(), requestPaint() or by changing
the current canvas window.
*/
/*!
\qmlsignal QtQuick2::Canvas::onPainted()
This handler is called after all context painting commands are executed and
the Canvas has been rendered.
*/
QT_END_NAMESPACE