Added QSGPainterNode abstraction to QSGAdaptationLayer

This allows the scenegraph backend to customize how QSGPainterNodes are
rendered.

Change-Id: I640dcf121d0be6bda615cf30591d502329fc89d0
Reviewed-by: Lars Knoll <lars.knoll@digia.com>
Reviewed-by: Gunnar Sletta <gunnar@sletta.org>

1 files changed, 427 insertions, 0 deletions

diff --git a/src/quick/scenegraph/util/qsgdefaultpainternode.cpp b/src/quick/scenegraph/util/qsgdefaultpainternode.cpp
new file mode 100644
index 0000000000..6135d958d5
--- /dev/null
+++ b/src/quick/scenegraph/util/qsgdefaultpainternode.cpp
@@ -0,0 +1,427 @@
+/****************************************************************************
+**
+** Copyright (C) 2014 Digia Plc and/or its subsidiary(-ies).
+** Contact: http://www.qt-project.org/legal
+**
+** This file is part of the QtQuick module of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL21$
+** 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 or version 3 as published by the Free
+** Software Foundation and appearing in the file LICENSE.LGPLv21 and
+** LICENSE.LGPLv3 included in the packaging of this file. Please review the
+** following information to ensure the GNU Lesser General Public License
+** requirements will be met: https://www.gnu.org/licenses/lgpl.html and
+** 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.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#include "qsgdefaultpainternode_p.h"
+
+#include <QtQuick/private/qquickpainteditem_p.h>
+
+#include <QtQuick/private/qsgcontext_p.h>
+#include <private/qopenglextensions_p.h>
+#include <qopenglframebufferobject.h>
+#include <qopenglfunctions.h>
+#include <qopenglpaintdevice.h>
+#include <qmath.h>
+#include <qpainter.h>
+
+QT_BEGIN_NAMESPACE
+
+#define QT_MINIMUM_DYNAMIC_FBO_SIZE 64U
+
+QSGPainterTexture::QSGPainterTexture()
+    : QSGPlainTexture()
+{
+    m_retain_image = true;
+}
+
+void QSGPainterTexture::bind()
+{
+    if (m_dirty_rect.isNull()) {
+        QSGPlainTexture::bind();
+        return;
+    }
+
+    setImage(m_image);
+    QSGPlainTexture::bind();
+
+    m_dirty_rect = QRect();
+}
+
+QSGDefaultPainterNode::QSGDefaultPainterNode(QQuickPaintedItem *item)
+    : QSGPainterNode()
+    , m_preferredRenderTarget(QQuickPaintedItem::Image)
+    , m_actualRenderTarget(QQuickPaintedItem::Image)
+    , m_item(item)
+    , m_fbo(0)
+    , m_multisampledFbo(0)
+    , m_geometry(QSGGeometry::defaultAttributes_TexturedPoint2D(), 4)
+    , m_texture(0)
+    , m_gl_device(0)
+    , m_dirtyContents(false)
+    , m_opaquePainting(false)
+    , m_linear_filtering(false)
+    , m_mipmapping(false)
+    , m_smoothPainting(false)
+    , m_extensionsChecked(false)
+    , m_multisamplingSupported(false)
+    , m_fastFBOResizing(false)
+    , m_fillColor(Qt::transparent)
+    , m_contentsScale(1.0)
+    , m_dirtyGeometry(false)
+    , m_dirtyRenderTarget(false)
+    , m_dirtyTexture(false)
+{
+    m_context = static_cast<QQuickPaintedItemPrivate *>(QObjectPrivate::get(item))->sceneGraphRenderContext();
+
+    setMaterial(&m_materialO);
+    setOpaqueMaterial(&m_material);
+    setGeometry(&m_geometry);
+
+#ifdef QSG_RUNTIME_DESCRIPTION
+    qsgnode_set_description(this, QString::fromLatin1("QQuickPaintedItem(%1):%2").arg(QString::fromLatin1(item->metaObject()->className())).arg(item->objectName()));
+#endif
+}
+
+QSGDefaultPainterNode::~QSGDefaultPainterNode()
+{
+    delete m_texture;
+    delete m_fbo;
+    delete m_multisampledFbo;
+    delete m_gl_device;
+}
+
+void QSGDefaultPainterNode::paint()
+{
+    QRect dirtyRect = m_dirtyRect.isNull() ? QRect(0, 0, m_size.width(), m_size.height()) : m_dirtyRect;
+
+    QPainter painter;
+    if (m_actualRenderTarget == QQuickPaintedItem::Image) {
+        if (m_image.isNull())
+            return;
+        painter.begin(&m_image);
+    } else {
+        if (!m_gl_device) {
+            m_gl_device = new QOpenGLPaintDevice(m_fboSize);
+            m_gl_device->setPaintFlipped(true);
+        }
+
+        if (m_multisampledFbo)
+            m_multisampledFbo->bind();
+        else
+            m_fbo->bind();
+
+        painter.begin(m_gl_device);
+    }
+
+    if (m_smoothPainting) {
+        painter.setRenderHints(QPainter::Antialiasing | QPainter::TextAntialiasing | QPainter::SmoothPixmapTransform);
+    }
+
+    painter.scale(m_contentsScale, m_contentsScale);
+
+    QRect sclip(qFloor(dirtyRect.x()/m_contentsScale),
+                qFloor(dirtyRect.y()/m_contentsScale),
+                qCeil(dirtyRect.width()/m_contentsScale+dirtyRect.x()/m_contentsScale-qFloor(dirtyRect.x()/m_contentsScale)),
+                qCeil(dirtyRect.height()/m_contentsScale+dirtyRect.y()/m_contentsScale-qFloor(dirtyRect.y()/m_contentsScale)));
+
+    if (!m_dirtyRect.isNull())
+        painter.setClipRect(sclip);
+
+    painter.setCompositionMode(QPainter::CompositionMode_Source);
+    painter.fillRect(sclip, m_fillColor);
+    painter.setCompositionMode(QPainter::CompositionMode_SourceOver);
+
+    m_item->paint(&painter);
+    painter.end();
+
+    if (m_actualRenderTarget == QQuickPaintedItem::Image) {
+        m_texture->setImage(m_image);
+        m_texture->setDirtyRect(dirtyRect);
+    } else if (m_multisampledFbo) {
+        QOpenGLFramebufferObject::blitFramebuffer(m_fbo, dirtyRect, m_multisampledFbo, dirtyRect);
+    }
+
+    if (m_multisampledFbo)
+        m_multisampledFbo->release();
+    else if (m_fbo)
+        m_fbo->release();
+
+    m_dirtyRect = QRect();
+}
+
+void QSGDefaultPainterNode::update()
+{
+    if (m_dirtyRenderTarget)
+        updateRenderTarget();
+    if (m_dirtyGeometry)
+        updateGeometry();
+    if (m_dirtyTexture)
+        updateTexture();
+
+    if (m_dirtyContents)
+        paint();
+
+    m_dirtyGeometry = false;
+    m_dirtyRenderTarget = false;
+    m_dirtyTexture = false;
+    m_dirtyContents = false;
+}
+
+void QSGDefaultPainterNode::updateTexture()
+{
+    m_texture->setHasAlphaChannel(!m_opaquePainting);
+    m_material.setTexture(m_texture);
+    m_materialO.setTexture(m_texture);
+
+    markDirty(DirtyMaterial);
+}
+
+void QSGDefaultPainterNode::updateGeometry()
+{
+    QRectF source;
+    if (m_actualRenderTarget == QQuickPaintedItem::Image)
+        source = QRectF(0, 0, 1, 1);
+    else
+        source = QRectF(0, 0, qreal(m_size.width()) / m_fboSize.width(), qreal(m_size.height()) / m_fboSize.height());
+    QRectF dest(0, 0, m_size.width(), m_size.height());
+    if (m_actualRenderTarget == QQuickPaintedItem::InvertedYFramebufferObject)
+        dest = QRectF(QPointF(0, m_size.height()), QPointF(m_size.width(), 0));
+    QSGGeometry::updateTexturedRectGeometry(&m_geometry,
+                                            dest,
+                                            source);
+    markDirty(DirtyGeometry);
+}
+
+void QSGDefaultPainterNode::updateRenderTarget()
+{
+    if (!m_extensionsChecked) {
+        const QSet<QByteArray> extensions = m_context->openglContext()->extensions();
+        m_multisamplingSupported = extensions.contains(QByteArrayLiteral("GL_EXT_framebuffer_multisample"))
+            && extensions.contains(QByteArrayLiteral("GL_EXT_framebuffer_blit"));
+        m_extensionsChecked = true;
+    }
+
+    m_dirtyContents = true;
+
+    QQuickPaintedItem::RenderTarget oldTarget = m_actualRenderTarget;
+    if (m_preferredRenderTarget == QQuickPaintedItem::Image) {
+        m_actualRenderTarget = QQuickPaintedItem::Image;
+    } else {
+        if (!m_multisamplingSupported && m_smoothPainting)
+            m_actualRenderTarget = QQuickPaintedItem::Image;
+        else
+            m_actualRenderTarget = m_preferredRenderTarget;
+    }
+    if (oldTarget != m_actualRenderTarget) {
+        m_image = QImage();
+        delete m_fbo;
+        delete m_multisampledFbo;
+        delete m_gl_device;
+        m_fbo = m_multisampledFbo = 0;
+        m_gl_device = 0;
+    }
+
+    if (m_actualRenderTarget == QQuickPaintedItem::FramebufferObject ||
+            m_actualRenderTarget == QQuickPaintedItem::InvertedYFramebufferObject) {
+        const QOpenGLContext *ctx = m_context->openglContext();
+        if (m_fbo && !m_dirtyGeometry && (!ctx->format().samples() || !m_multisamplingSupported))
+            return;
+
+        if (m_fboSize.isEmpty())
+            updateFBOSize();
+
+        delete m_fbo;
+        delete m_multisampledFbo;
+        m_fbo = m_multisampledFbo = 0;
+        if (m_gl_device)
+            m_gl_device->setSize(m_fboSize);
+
+        if (m_smoothPainting && ctx->format().samples() && m_multisamplingSupported) {
+            {
+                QOpenGLFramebufferObjectFormat format;
+                format.setAttachment(QOpenGLFramebufferObject::CombinedDepthStencil);
+                format.setSamples(8);
+                m_multisampledFbo = new QOpenGLFramebufferObject(m_fboSize, format);
+            }
+            {
+                QOpenGLFramebufferObjectFormat format;
+                format.setAttachment(QOpenGLFramebufferObject::NoAttachment);
+                m_fbo = new QOpenGLFramebufferObject(m_fboSize, format);
+            }
+        } else {
+            QOpenGLFramebufferObjectFormat format;
+            format.setAttachment(QOpenGLFramebufferObject::CombinedDepthStencil);
+            m_fbo = new QOpenGLFramebufferObject(m_fboSize, format);
+        }
+    } else {
+        if (!m_image.isNull() && !m_dirtyGeometry)
+            return;
+
+        m_image = QImage(m_size, QImage::Format_ARGB32_Premultiplied);
+        m_image.fill(Qt::transparent);
+    }
+
+    QSGPainterTexture *texture = new QSGPainterTexture;
+    if (m_actualRenderTarget == QQuickPaintedItem::Image) {
+        texture->setOwnsTexture(true);
+        texture->setTextureSize(m_size);
+    } else {
+        texture->setTextureId(m_fbo->texture());
+        texture->setOwnsTexture(false);
+        texture->setTextureSize(m_fboSize);
+    }
+
+    if (m_texture)
+        delete m_texture;
+
+    texture->setTextureSize(m_size);
+    m_texture = texture;
+}
+
+void QSGDefaultPainterNode::updateFBOSize()
+{
+    int fboWidth;
+    int fboHeight;
+    if (m_fastFBOResizing) {
+        fboWidth = qMax(QT_MINIMUM_DYNAMIC_FBO_SIZE, qNextPowerOfTwo(m_size.width() - 1));
+        fboHeight = qMax(QT_MINIMUM_DYNAMIC_FBO_SIZE, qNextPowerOfTwo(m_size.height() - 1));
+    } else {
+        QSize minimumFBOSize = m_context->sceneGraphContext()->minimumFBOSize();
+        fboWidth = qMax(minimumFBOSize.width(), m_size.width());
+        fboHeight = qMax(minimumFBOSize.height(), m_size.height());
+    }
+
+    m_fboSize = QSize(fboWidth, fboHeight);
+}
+
+void QSGDefaultPainterNode::setPreferredRenderTarget(QQuickPaintedItem::RenderTarget target)
+{
+    if (m_preferredRenderTarget == target)
+        return;
+
+    m_preferredRenderTarget = target;
+
+    m_dirtyRenderTarget = true;
+    m_dirtyGeometry = true;
+    m_dirtyTexture = true;
+}
+
+void QSGDefaultPainterNode::setSize(const QSize &size)
+{
+    if (size == m_size)
+        return;
+
+    m_size = size;
+    updateFBOSize();
+
+    if (m_fbo)
+        m_dirtyRenderTarget = m_fbo->size() != m_fboSize || m_dirtyRenderTarget;
+    else
+        m_dirtyRenderTarget = true;
+    m_dirtyGeometry = true;
+    m_dirtyTexture = true;
+}
+
+void QSGDefaultPainterNode::setDirty(const QRect &dirtyRect)
+{
+    m_dirtyContents = true;
+    m_dirtyRect = dirtyRect;
+
+    if (m_mipmapping)
+        m_dirtyTexture = true;
+
+    markDirty(DirtyMaterial);
+}
+
+void QSGDefaultPainterNode::setOpaquePainting(bool opaque)
+{
+    if (opaque == m_opaquePainting)
+        return;
+
+    m_opaquePainting = opaque;
+    m_dirtyTexture = true;
+}
+
+void QSGDefaultPainterNode::setLinearFiltering(bool linearFiltering)
+{
+    if (linearFiltering == m_linear_filtering)
+        return;
+
+    m_linear_filtering = linearFiltering;
+
+    m_material.setFiltering(linearFiltering ? QSGTexture::Linear : QSGTexture::Nearest);
+    m_materialO.setFiltering(linearFiltering ? QSGTexture::Linear : QSGTexture::Nearest);
+    markDirty(DirtyMaterial);
+}
+
+void QSGDefaultPainterNode::setMipmapping(bool mipmapping)
+{
+    if (mipmapping == m_mipmapping)
+        return;
+
+    m_mipmapping = mipmapping;
+    m_material.setMipmapFiltering(mipmapping ? QSGTexture::Linear : QSGTexture::None);
+    m_materialO.setMipmapFiltering(mipmapping ? QSGTexture::Linear : QSGTexture::None);
+    m_dirtyTexture = true;
+}
+
+void QSGDefaultPainterNode::setSmoothPainting(bool s)
+{
+    if (s == m_smoothPainting)
+        return;
+
+    m_smoothPainting = s;
+    m_dirtyRenderTarget = true;
+}
+
+void QSGDefaultPainterNode::setFillColor(const QColor &c)
+{
+    if (c == m_fillColor)
+        return;
+
+    m_fillColor = c;
+    markDirty(DirtyMaterial);
+}
+
+void QSGDefaultPainterNode::setContentsScale(qreal s)
+{
+    if (s == m_contentsScale)
+        return;
+
+    m_contentsScale = s;
+    markDirty(DirtyMaterial);
+}
+
+void QSGDefaultPainterNode::setFastFBOResizing(bool dynamic)
+{
+    m_fastFBOResizing = dynamic;
+}
+
+QImage QSGDefaultPainterNode::toImage() const
+{
+    if (m_actualRenderTarget == QQuickPaintedItem::Image)
+        return m_image;
+    else
+        return m_fbo->toImage();
+}
+
+QT_END_NAMESPACE