455 lines
15 KiB
C++
455 lines
15 KiB
C++
/****************************************************************************
|
|
**
|
|
** Copyright (C) 2017 The Qt Company Ltd.
|
|
** Contact: https://www.qt.io/licensing/
|
|
**
|
|
** This file is part of the examples of the Qt Toolkit.
|
|
**
|
|
** $QT_BEGIN_LICENSE:BSD$
|
|
** 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 The Qt Company. For licensing terms
|
|
** and conditions see https://www.qt.io/terms-conditions. For further
|
|
** information use the contact form at https://www.qt.io/contact-us.
|
|
**
|
|
** BSD License Usage
|
|
** Alternatively, you may use this file under the terms of the BSD license
|
|
** as follows:
|
|
**
|
|
** "Redistribution and use in source and binary forms, with or without
|
|
** modification, are permitted provided that the following conditions are
|
|
** met:
|
|
** * Redistributions of source code must retain the above copyright
|
|
** notice, this list of conditions and the following disclaimer.
|
|
** * Redistributions in binary form must reproduce the above copyright
|
|
** notice, this list of conditions and the following disclaimer in
|
|
** the documentation and/or other materials provided with the
|
|
** distribution.
|
|
** * Neither the name of The Qt Company Ltd nor the names of its
|
|
** contributors may be used to endorse or promote products derived
|
|
** from this software without specific prior written permission.
|
|
**
|
|
**
|
|
** THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
|
|
** "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
|
|
** LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
|
|
** A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
|
|
** OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
|
|
** SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
|
|
** LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
|
|
** DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
|
|
** THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
|
|
** (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
|
|
** OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE."
|
|
**
|
|
** $QT_END_LICENSE$
|
|
**
|
|
****************************************************************************/
|
|
|
|
#include "window_multithreaded.h"
|
|
#include "cuberenderer.h"
|
|
#include <QOpenGLContext>
|
|
#include <QOpenGLFunctions>
|
|
#include <QOpenGLFramebufferObject>
|
|
#include <QOpenGLShaderProgram>
|
|
#include <QOpenGLVertexArrayObject>
|
|
#include <QOpenGLBuffer>
|
|
#include <QOpenGLVertexArrayObject>
|
|
#include <QOffscreenSurface>
|
|
#include <QQmlEngine>
|
|
#include <QQmlComponent>
|
|
#include <QQuickItem>
|
|
#include <QQuickWindow>
|
|
#include <QQuickRenderControl>
|
|
#include <QCoreApplication>
|
|
|
|
/*
|
|
This implementation runs the Qt Quick scenegraph's sync and render phases on a
|
|
separate, dedicated thread. Rendering the cube using our custom OpenGL engine
|
|
happens on that thread as well. This is similar to the built-in threaded
|
|
render loop, but does not support all the features. There is no support for
|
|
getting Animators running on the render thread for example.
|
|
|
|
We choose to use QObject's event mechanism to communicate with the QObject
|
|
living on the render thread. An alternative would be to subclass QThread and
|
|
reimplement run() with a custom event handling approach, like
|
|
QSGThreadedRenderLoop does. That would potentially lead to better results but
|
|
is also more complex.
|
|
*/
|
|
|
|
static const QEvent::Type INIT = QEvent::Type(QEvent::User + 1);
|
|
static const QEvent::Type RENDER = QEvent::Type(QEvent::User + 2);
|
|
static const QEvent::Type RESIZE = QEvent::Type(QEvent::User + 3);
|
|
static const QEvent::Type STOP = QEvent::Type(QEvent::User + 4);
|
|
|
|
static const QEvent::Type UPDATE = QEvent::Type(QEvent::User + 5);
|
|
|
|
QuickRenderer::QuickRenderer()
|
|
: m_context(nullptr),
|
|
m_surface(nullptr),
|
|
m_fbo(nullptr),
|
|
m_window(nullptr),
|
|
m_quickWindow(nullptr),
|
|
m_renderControl(nullptr),
|
|
m_cubeRenderer(nullptr),
|
|
m_quit(false)
|
|
{
|
|
}
|
|
|
|
void QuickRenderer::requestInit()
|
|
{
|
|
QCoreApplication::postEvent(this, new QEvent(INIT));
|
|
}
|
|
|
|
void QuickRenderer::requestRender()
|
|
{
|
|
QCoreApplication::postEvent(this, new QEvent(RENDER));
|
|
}
|
|
|
|
void QuickRenderer::requestResize()
|
|
{
|
|
QCoreApplication::postEvent(this, new QEvent(RESIZE));
|
|
}
|
|
|
|
void QuickRenderer::requestStop()
|
|
{
|
|
QCoreApplication::postEvent(this, new QEvent(STOP));
|
|
}
|
|
|
|
bool QuickRenderer::event(QEvent *e)
|
|
{
|
|
QMutexLocker lock(&m_mutex);
|
|
|
|
switch (int(e->type())) {
|
|
case INIT:
|
|
init();
|
|
return true;
|
|
case RENDER:
|
|
render(&lock);
|
|
return true;
|
|
case RESIZE:
|
|
if (m_cubeRenderer)
|
|
m_cubeRenderer->resize(m_window->width(), m_window->height());
|
|
return true;
|
|
case STOP:
|
|
cleanup();
|
|
return true;
|
|
default:
|
|
return QObject::event(e);
|
|
}
|
|
}
|
|
|
|
void QuickRenderer::init()
|
|
{
|
|
m_context->makeCurrent(m_surface);
|
|
|
|
// Pass our offscreen surface to the cube renderer just so that it will
|
|
// have something is can make current during cleanup. QOffscreenSurface,
|
|
// just like QWindow, must always be created on the gui thread (as it might
|
|
// be backed by an actual QWindow).
|
|
m_cubeRenderer = new CubeRenderer(m_surface);
|
|
m_cubeRenderer->resize(m_window->width(), m_window->height());
|
|
|
|
m_renderControl->initialize(m_context);
|
|
}
|
|
|
|
void QuickRenderer::cleanup()
|
|
{
|
|
m_context->makeCurrent(m_surface);
|
|
|
|
m_renderControl->invalidate();
|
|
|
|
delete m_fbo;
|
|
m_fbo = nullptr;
|
|
|
|
delete m_cubeRenderer;
|
|
m_cubeRenderer = nullptr;
|
|
|
|
m_context->doneCurrent();
|
|
m_context->moveToThread(QCoreApplication::instance()->thread());
|
|
|
|
m_cond.wakeOne();
|
|
}
|
|
|
|
void QuickRenderer::ensureFbo()
|
|
{
|
|
if (m_fbo && m_fbo->size() != m_window->size() * m_window->devicePixelRatio()) {
|
|
delete m_fbo;
|
|
m_fbo = nullptr;
|
|
}
|
|
|
|
if (!m_fbo) {
|
|
m_fbo = new QOpenGLFramebufferObject(m_window->size() * m_window->devicePixelRatio(),
|
|
QOpenGLFramebufferObject::CombinedDepthStencil);
|
|
m_quickWindow->setRenderTarget(m_fbo);
|
|
}
|
|
}
|
|
|
|
void QuickRenderer::render(QMutexLocker *lock)
|
|
{
|
|
Q_ASSERT(QThread::currentThread() != m_window->thread());
|
|
|
|
if (!m_context->makeCurrent(m_surface)) {
|
|
qWarning("Failed to make context current on render thread");
|
|
return;
|
|
}
|
|
|
|
ensureFbo();
|
|
|
|
// Synchronization and rendering happens here on the render thread.
|
|
m_renderControl->sync();
|
|
|
|
// The gui thread can now continue.
|
|
m_cond.wakeOne();
|
|
lock->unlock();
|
|
|
|
// Meanwhile on this thread continue with the actual rendering (into the FBO first).
|
|
m_renderControl->render();
|
|
m_context->functions()->glFlush();
|
|
|
|
// The cube renderer uses its own context, no need to bother with the state here.
|
|
|
|
// Get something onto the screen using our custom OpenGL engine.
|
|
QMutexLocker quitLock(&m_quitMutex);
|
|
if (!m_quit)
|
|
m_cubeRenderer->render(m_window, m_context, m_fbo->texture());
|
|
}
|
|
|
|
void QuickRenderer::aboutToQuit()
|
|
{
|
|
QMutexLocker lock(&m_quitMutex);
|
|
m_quit = true;
|
|
}
|
|
|
|
class RenderControl : public QQuickRenderControl
|
|
{
|
|
public:
|
|
RenderControl(QWindow *w) : m_window(w) { }
|
|
QWindow *renderWindow(QPoint *offset) override;
|
|
|
|
private:
|
|
QWindow *m_window;
|
|
};
|
|
|
|
WindowMultiThreaded::WindowMultiThreaded()
|
|
: m_qmlComponent(nullptr),
|
|
m_rootItem(nullptr),
|
|
m_quickInitialized(false),
|
|
m_psrRequested(false)
|
|
{
|
|
setSurfaceType(QSurface::OpenGLSurface);
|
|
|
|
QSurfaceFormat format;
|
|
// Qt Quick may need a depth and stencil buffer. Always make sure these are available.
|
|
format.setDepthBufferSize(16);
|
|
format.setStencilBufferSize(8);
|
|
setFormat(format);
|
|
|
|
m_context = new QOpenGLContext;
|
|
m_context->setFormat(format);
|
|
m_context->create();
|
|
|
|
m_offscreenSurface = new QOffscreenSurface;
|
|
// Pass m_context->format(), not format. Format does not specify and color buffer
|
|
// sizes, while the context, that has just been created, reports a format that has
|
|
// these values filled in. Pass this to the offscreen surface to make sure it will be
|
|
// compatible with the context's configuration.
|
|
m_offscreenSurface->setFormat(m_context->format());
|
|
m_offscreenSurface->create();
|
|
|
|
m_renderControl = new RenderControl(this);
|
|
|
|
// Create a QQuickWindow that is associated with out render control. Note that this
|
|
// window never gets created or shown, meaning that it will never get an underlying
|
|
// native (platform) window.
|
|
m_quickWindow = new QQuickWindow(m_renderControl);
|
|
|
|
// Create a QML engine.
|
|
m_qmlEngine = new QQmlEngine;
|
|
if (!m_qmlEngine->incubationController())
|
|
m_qmlEngine->setIncubationController(m_quickWindow->incubationController());
|
|
|
|
m_quickRenderer = new QuickRenderer;
|
|
m_quickRenderer->setContext(m_context);
|
|
|
|
// These live on the gui thread. Just give access to them on the render thread.
|
|
m_quickRenderer->setSurface(m_offscreenSurface);
|
|
m_quickRenderer->setWindow(this);
|
|
m_quickRenderer->setQuickWindow(m_quickWindow);
|
|
m_quickRenderer->setRenderControl(m_renderControl);
|
|
|
|
m_quickRendererThread = new QThread;
|
|
|
|
// Notify the render control that some scenegraph internals have to live on
|
|
// m_quickRenderThread.
|
|
m_renderControl->prepareThread(m_quickRendererThread);
|
|
|
|
// The QOpenGLContext and the QObject representing the rendering logic on
|
|
// the render thread must live on that thread.
|
|
m_context->moveToThread(m_quickRendererThread);
|
|
m_quickRenderer->moveToThread(m_quickRendererThread);
|
|
|
|
m_quickRendererThread->start();
|
|
|
|
// Now hook up the signals. For simplicy we don't differentiate
|
|
// between renderRequested (only render is needed, no sync) and
|
|
// sceneChanged (polish and sync is needed too).
|
|
connect(m_renderControl, &QQuickRenderControl::renderRequested, this, &WindowMultiThreaded::requestUpdate);
|
|
connect(m_renderControl, &QQuickRenderControl::sceneChanged, this, &WindowMultiThreaded::requestUpdate);
|
|
}
|
|
|
|
WindowMultiThreaded::~WindowMultiThreaded()
|
|
{
|
|
// Release resources and move the context ownership back to this thread.
|
|
m_quickRenderer->mutex()->lock();
|
|
m_quickRenderer->requestStop();
|
|
m_quickRenderer->cond()->wait(m_quickRenderer->mutex());
|
|
m_quickRenderer->mutex()->unlock();
|
|
|
|
m_quickRendererThread->quit();
|
|
m_quickRendererThread->wait();
|
|
|
|
delete m_renderControl;
|
|
delete m_qmlComponent;
|
|
delete m_quickWindow;
|
|
delete m_qmlEngine;
|
|
|
|
delete m_offscreenSurface;
|
|
delete m_context;
|
|
}
|
|
|
|
void WindowMultiThreaded::requestUpdate()
|
|
{
|
|
if (m_quickInitialized && !m_psrRequested) {
|
|
m_psrRequested = true;
|
|
QCoreApplication::postEvent(this, new QEvent(UPDATE));
|
|
}
|
|
}
|
|
|
|
bool WindowMultiThreaded::event(QEvent *e)
|
|
{
|
|
if (e->type() == UPDATE) {
|
|
polishSyncAndRender();
|
|
m_psrRequested = false;
|
|
return true;
|
|
} else if (e->type() == QEvent::Close) {
|
|
// Avoid rendering on the render thread when the window is about to
|
|
// close. Once a QWindow is closed, the underlying platform window will
|
|
// go away, even though the QWindow instance itself is still
|
|
// valid. Operations like swapBuffers() are futile and only result in
|
|
// warnings afterwards. Prevent this.
|
|
m_quickRenderer->aboutToQuit();
|
|
}
|
|
return QWindow::event(e);
|
|
}
|
|
|
|
void WindowMultiThreaded::polishSyncAndRender()
|
|
{
|
|
Q_ASSERT(QThread::currentThread() == thread());
|
|
|
|
// Polishing happens on the gui thread.
|
|
m_renderControl->polishItems();
|
|
// Sync happens on the render thread with the gui thread (this one) blocked.
|
|
QMutexLocker lock(m_quickRenderer->mutex());
|
|
m_quickRenderer->requestRender();
|
|
// Wait until sync is complete.
|
|
m_quickRenderer->cond()->wait(m_quickRenderer->mutex());
|
|
// Rendering happens on the render thread without blocking the gui (main)
|
|
// thread. This is good because the blocking swap (waiting for vsync)
|
|
// happens on the render thread, not blocking other work.
|
|
}
|
|
|
|
void WindowMultiThreaded::run()
|
|
{
|
|
disconnect(m_qmlComponent, &QQmlComponent::statusChanged, this, &WindowMultiThreaded::run);
|
|
|
|
if (m_qmlComponent->isError()) {
|
|
const QList<QQmlError> errorList = m_qmlComponent->errors();
|
|
for (const QQmlError &error : errorList)
|
|
qWarning() << error.url() << error.line() << error;
|
|
return;
|
|
}
|
|
|
|
QObject *rootObject = m_qmlComponent->create();
|
|
if (m_qmlComponent->isError()) {
|
|
const QList<QQmlError> errorList = m_qmlComponent->errors();
|
|
for (const QQmlError &error : errorList)
|
|
qWarning() << error.url() << error.line() << error;
|
|
return;
|
|
}
|
|
|
|
m_rootItem = qobject_cast<QQuickItem *>(rootObject);
|
|
if (!m_rootItem) {
|
|
qWarning("run: Not a QQuickItem");
|
|
delete rootObject;
|
|
return;
|
|
}
|
|
|
|
// The root item is ready. Associate it with the window.
|
|
m_rootItem->setParentItem(m_quickWindow->contentItem());
|
|
|
|
// Update item and rendering related geometries.
|
|
updateSizes();
|
|
|
|
m_quickInitialized = true;
|
|
|
|
// Initialize the render thread and perform the first polish/sync/render.
|
|
m_quickRenderer->requestInit();
|
|
polishSyncAndRender();
|
|
}
|
|
|
|
void WindowMultiThreaded::updateSizes()
|
|
{
|
|
// Behave like SizeRootObjectToView.
|
|
m_rootItem->setWidth(width());
|
|
m_rootItem->setHeight(height());
|
|
|
|
m_quickWindow->setGeometry(0, 0, width(), height());
|
|
}
|
|
|
|
void WindowMultiThreaded::startQuick(const QString &filename)
|
|
{
|
|
m_qmlComponent = new QQmlComponent(m_qmlEngine, QUrl(filename));
|
|
if (m_qmlComponent->isLoading())
|
|
connect(m_qmlComponent, &QQmlComponent::statusChanged, this, &WindowMultiThreaded::run);
|
|
else
|
|
run();
|
|
}
|
|
|
|
void WindowMultiThreaded::exposeEvent(QExposeEvent *)
|
|
{
|
|
if (isExposed()) {
|
|
if (!m_quickInitialized)
|
|
startQuick(QStringLiteral("qrc:/rendercontrol/demo.qml"));
|
|
}
|
|
}
|
|
|
|
void WindowMultiThreaded::resizeEvent(QResizeEvent *)
|
|
{
|
|
// If this is a resize after the scene is up and running, recreate the fbo and the
|
|
// Quick item and scene.
|
|
if (m_rootItem) {
|
|
updateSizes();
|
|
m_quickRenderer->requestResize();
|
|
polishSyncAndRender();
|
|
}
|
|
}
|
|
|
|
void WindowMultiThreaded::mousePressEvent(QMouseEvent *e)
|
|
{
|
|
// Use the constructor taking localPos and screenPos. That puts localPos into the
|
|
// event's localPos and windowPos, and screenPos into the event's screenPos. This way
|
|
// the windowPos in e is ignored and is replaced by localPos. This is necessary
|
|
// because QQuickWindow thinks of itself as a top-level window always.
|
|
QMouseEvent mappedEvent(e->type(), e->localPos(), e->screenPos(), e->button(), e->buttons(), e->modifiers());
|
|
QCoreApplication::sendEvent(m_quickWindow, &mappedEvent);
|
|
}
|
|
|
|
void WindowMultiThreaded::mouseReleaseEvent(QMouseEvent *e)
|
|
{
|
|
QMouseEvent mappedEvent(e->type(), e->localPos(), e->screenPos(), e->button(), e->buttons(), e->modifiers());
|
|
QCoreApplication::sendEvent(m_quickWindow, &mappedEvent);
|
|
}
|