Add RenderViewBuilder

Refactoring of what's in FrameGraphVisitor::visit

Will allow to unit tests this complex process

Change-Id: I6561bbefc9b67fbd73c5e30e09c5f3698896cbe7
Reviewed-by: Sean Harmer <sean.harmer@kdab.com>

1 files changed, 510 insertions, 0 deletions

diff --git a/src/render/backend/renderviewbuilder.cpp b/src/render/backend/renderviewbuilder.cpp
new file mode 100644
index 000000000..34bd8e61b
--- /dev/null
+++ b/src/render/backend/renderviewbuilder.cpp
@@ -0,0 +1,510 @@
+/****************************************************************************
+**
+** Copyright (C) 2016 Klaralvdalens Datakonsult AB (KDAB).
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of the Qt3D 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 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.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 3 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL3 included in the
+** packaging of this file. Please review the following information to
+** ensure the GNU Lesser General Public License version 3 requirements
+** will be met: https://www.gnu.org/licenses/lgpl-3.0.html.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 2.0 or (at your option) the GNU General
+** Public license version 3 or any later version approved by the KDE Free
+** Qt Foundation. The licenses are as published by the Free Software
+** Foundation and appearing in the file LICENSE.GPL2 and LICENSE.GPL3
+** included in the packaging of this file. Please review the following
+** information to ensure the GNU General Public License requirements will
+** be met: https://www.gnu.org/licenses/gpl-2.0.html and
+** https://www.gnu.org/licenses/gpl-3.0.html.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#include "renderviewbuilder_p.h"
+
+QT_BEGIN_NAMESPACE
+
+namespace Qt3DRender {
+
+namespace Render {
+
+const int RenderViewBuilder::m_optimalParallelJobCount = std::max(QThread::idealThreadCount(), 2);
+
+namespace {
+
+class SyncRenderViewCommandBuilders
+{
+public:
+    explicit SyncRenderViewCommandBuilders(const RenderViewInitializerJobPtr &renderViewJob,
+                                           const QVector<RenderViewBuilderJobPtr> &renderViewBuilderJobs,
+                                           Renderer *renderer)
+        : m_renderViewJob(renderViewJob)
+        , m_renderViewBuilderJobs(renderViewBuilderJobs)
+        , m_renderer(renderer)
+    {}
+
+    void operator()()
+    {
+        // Append all the commands and sort them
+        RenderView *rv = m_renderViewJob->renderView();
+
+        int totalCommandCount = 0;
+        for (const auto renderViewCommandBuilder : qAsConst(m_renderViewBuilderJobs))
+            totalCommandCount += renderViewCommandBuilder->commands().size();
+
+        QVector<RenderCommand *> commands;
+        commands.reserve(totalCommandCount);
+
+        // Reduction
+        for (const auto renderViewCommandBuilder : qAsConst(m_renderViewBuilderJobs))
+            commands += std::move(renderViewCommandBuilder->commands());
+        rv->setCommands(commands);
+
+        // Sort the commands
+        rv->sort();
+
+        // Enqueue our fully populated RenderView with the RenderThread
+        m_renderer->enqueueRenderView(rv, m_renderViewJob->submitOrderIndex());
+    }
+
+private:
+    RenderViewInitializerJobPtr m_renderViewJob;
+    QVector<RenderViewBuilderJobPtr> m_renderViewBuilderJobs;
+    Renderer *m_renderer;
+};
+
+class SyncFrustumCulling
+{
+public:
+    explicit SyncFrustumCulling(const RenderViewInitializerJobPtr &renderViewJob,
+                                const FrustumCullingJobPtr &frustumCulling)
+        : m_renderViewJob(renderViewJob)
+        , m_frustumCullingJob(frustumCulling)
+    {}
+
+    void operator()()
+    {
+        RenderView *rv = m_renderViewJob->renderView();
+
+        // Update matrices now that all transforms have been updated
+        rv->updateMatrices();
+
+        // Frustum culling
+        m_frustumCullingJob->setViewProjection(rv->viewProjectionMatrix());
+    }
+
+private:
+    RenderViewInitializerJobPtr m_renderViewJob;
+    FrustumCullingJobPtr m_frustumCullingJob;
+};
+
+class SyncRenderViewInitialization
+{
+public:
+    explicit SyncRenderViewInitialization(const RenderViewInitializerJobPtr &renderViewJob,
+                                          const FrustumCullingJobPtr &frustumCullingJob,
+                                          const FilterLayerEntityJobPtr &filterEntityByLayerJob,
+                                          const QVector<MaterialParameterGathererJobPtr> &materialGathererJobs,
+                                          const QVector<RenderViewBuilderJobPtr> &renderViewBuilderJobs)
+        : m_renderViewJob(renderViewJob)
+        , m_frustumCullingJob(frustumCullingJob)
+        , m_filterEntityByLayerJob(filterEntityByLayerJob)
+        , m_materialGathererJobs(materialGathererJobs)
+        , m_renderViewBuilderJobs(renderViewBuilderJobs)
+    {}
+
+    void operator()()
+    {
+        RenderView *rv = m_renderViewJob->renderView();
+
+        // Layer filtering
+        m_filterEntityByLayerJob->setHasLayerFilter(rv->hasLayerFilter());
+        m_filterEntityByLayerJob->setLayers(rv->layerFilter());
+
+        // Material Parameter building
+        for (const auto materialGatherer : qAsConst(m_materialGathererJobs)) {
+            materialGatherer->setRenderPassFilter(const_cast<RenderPassFilter *>(rv->renderPassFilter()));
+            materialGatherer->setTechniqueFilter(const_cast<TechniqueFilter *>(rv->techniqueFilter()));
+        }
+
+        // Command builders
+        for (const auto renderViewCommandBuilder : qAsConst(m_renderViewBuilderJobs))
+            renderViewCommandBuilder->setRenderView(rv);
+
+        // Set whether frustum culling is enabled or not
+        m_frustumCullingJob->setActive(rv->frustumCulling());
+    }
+
+private:
+    RenderViewInitializerJobPtr m_renderViewJob;
+    FrustumCullingJobPtr m_frustumCullingJob;
+    FilterLayerEntityJobPtr m_filterEntityByLayerJob;
+    QVector<MaterialParameterGathererJobPtr> m_materialGathererJobs;
+    QVector<RenderViewBuilderJobPtr> m_renderViewBuilderJobs;
+};
+
+class SyncRenderCommandBuilding
+{
+public:
+    explicit SyncRenderCommandBuilding(const RenderViewInitializerJobPtr &renderViewJob,
+                                       const FrustumCullingJobPtr &frustumCullingJob,
+                                       const FilterLayerEntityJobPtr &filterEntityByLayerJob,
+                                       const LightGathererPtr &lightGathererJob,
+                                       const RenderableEntityFilterPtr &renderableEntityFilterJob,
+                                       const ComputableEntityFilterPtr &computableEntityFilterJob,
+                                       const QVector<MaterialParameterGathererJobPtr> &materialGathererJobs,
+                                       const QVector<RenderViewBuilderJobPtr> &renderViewBuilderJobs)
+        : m_renderViewJob(renderViewJob)
+        , m_frustumCullingJob(frustumCullingJob)
+        , m_filterEntityByLayerJob(filterEntityByLayerJob)
+        , m_lightGathererJob(lightGathererJob)
+        , m_renderableEntityFilterJob(renderableEntityFilterJob)
+        , m_computableEntityFilterJob(computableEntityFilterJob)
+        , m_materialGathererJobs(materialGathererJobs)
+        , m_renderViewBuilderJobs(renderViewBuilderJobs)
+    {}
+
+    void operator()()
+    {
+        // Set the result of previous job computations
+        // for final RenderCommand building
+        RenderView *rv = m_renderViewJob->renderView();
+
+        if (!rv->noDraw()) {
+            // Set the light sources
+            rv->setLightSources(std::move(m_lightGathererJob->lights()));
+
+            // Remove all entities from the compute and renderable vectors that aren't in the filtered layer vector
+            QVector<Entity *> filteredEntities = m_filterEntityByLayerJob->filteredEntities();
+
+            // We sort the vector so that the removal can then be performed linearly
+            if (!rv->isCompute()) {
+                QVector<Entity *> renderableEntities = std::move(m_renderableEntityFilterJob->filteredEntities());
+                std::sort(renderableEntities.begin(), renderableEntities.end());
+                RenderViewBuilder::removeEntitiesNotInSubset(renderableEntities, filteredEntities);
+
+                if (rv->frustumCulling())
+                    RenderViewBuilder::removeEntitiesNotInSubset(renderableEntities, m_frustumCullingJob->visibleEntities());
+
+                // Split among the number of command builders
+                const int packetSize = renderableEntities.size() / RenderViewBuilder::optimalJobCount();
+                for (auto i = 0, m = RenderViewBuilder::optimalJobCount(); i < m; ++i) {
+                    const RenderViewBuilderJobPtr renderViewCommandBuilder = m_renderViewBuilderJobs.at(i);
+                    if (i == m - 1)
+                        renderViewCommandBuilder->setRenderables(renderableEntities.mid(i * packetSize, packetSize + renderableEntities.size() % m));
+                    else
+                        renderViewCommandBuilder->setRenderables(renderableEntities.mid(i * packetSize, packetSize));
+                }
+            } else {
+                QVector<Entity *> computableEntities = std::move(m_computableEntityFilterJob->filteredEntities());
+                std::sort(computableEntities.begin(), computableEntities.end());
+                RenderViewBuilder::removeEntitiesNotInSubset(computableEntities, filteredEntities);
+
+                // Split among the number of command builders
+                const int packetSize = computableEntities.size() / RenderViewBuilder::optimalJobCount();
+                for (auto i = 0, m = RenderViewBuilder::optimalJobCount(); i < m; ++i) {
+                    const RenderViewBuilderJobPtr renderViewCommandBuilder = m_renderViewBuilderJobs.at(i);
+                    if (i == m - 1)
+                        renderViewCommandBuilder->setRenderables(computableEntities.mid(i * packetSize, packetSize + computableEntities.size() % m));
+                    else
+                        renderViewCommandBuilder->setRenderables(computableEntities.mid(i * packetSize, packetSize));
+                }
+            }
+
+            // Reduction
+            QHash<Qt3DCore::QNodeId, QVector<RenderPassParameterData>> params;
+            for (const auto materialGatherer : qAsConst(m_materialGathererJobs))
+                params.unite(materialGatherer->materialToPassAndParameter());
+            // Set all required data on the RenderView for final processing
+            rv->setMaterialParameterTable(std::move(params));
+        }
+    }
+
+private:
+    RenderViewInitializerJobPtr m_renderViewJob;
+    FrustumCullingJobPtr m_frustumCullingJob;
+    FilterLayerEntityJobPtr m_filterEntityByLayerJob;
+    LightGathererPtr m_lightGathererJob;
+    RenderableEntityFilterPtr m_renderableEntityFilterJob;
+    ComputableEntityFilterPtr m_computableEntityFilterJob;
+    QVector<MaterialParameterGathererJobPtr> m_materialGathererJobs;
+    QVector<RenderViewBuilderJobPtr> m_renderViewBuilderJobs;
+};
+
+class SetClearDrawBufferIndex
+{
+public:
+    explicit SetClearDrawBufferIndex(const RenderViewInitializerJobPtr &renderViewJob)
+        : m_renderViewJob(renderViewJob)
+    {}
+
+    void operator()()
+    {
+        RenderView *rv = m_renderViewJob->renderView();
+        QVector<ClearBufferInfo> &clearBuffersInfo = rv->specificClearColorBufferInfo();
+        const AttachmentPack &attachmentPack = rv->attachmentPack();
+        for (ClearBufferInfo &clearBufferInfo : clearBuffersInfo)
+            clearBufferInfo.drawBufferIndex = attachmentPack.getDrawBufferIndex(clearBufferInfo.attchmentPoint);
+
+    }
+
+private:
+    RenderViewInitializerJobPtr m_renderViewJob;
+};
+
+} // anonymous
+
+RenderViewBuilder::RenderViewBuilder(Render::FrameGraphNode *leafNode, int renderViewIndex, Renderer *renderer)
+    : m_renderViewIndex(renderViewIndex)
+    , m_renderer(renderer)
+    , m_renderViewJob(RenderViewInitializerJobPtr::create())
+    , m_filterEntityByLayerJob(Render::FilterLayerEntityJobPtr::create())
+    , m_lightGathererJob(Render::LightGathererPtr::create())
+    , m_renderableEntityFilterJob(RenderableEntityFilterPtr::create())
+    , m_computableEntityFilterJob(ComputableEntityFilterPtr::create())
+    , m_frustumCullingJob(Render::FrustumCullingJobPtr::create())
+    , m_syncFrustumCullingJob(SynchronizerJobPtr::create(SyncFrustumCulling(m_renderViewJob, m_frustumCullingJob), JobTypes::SyncFrustumCulling))
+    , m_setClearDrawBufferIndexJob(SynchronizerJobPtr::create(SetClearDrawBufferIndex(m_renderViewJob), JobTypes::ClearBufferDrawIndex))
+{
+    // Init what we can here
+    EntityManager *entityManager = m_renderer->nodeManagers()->renderNodesManager();
+    m_filterEntityByLayerJob->setManager(m_renderer->nodeManagers());
+    m_renderableEntityFilterJob->setManager(entityManager);
+    m_computableEntityFilterJob->setManager(entityManager);
+    m_frustumCullingJob->setRoot(m_renderer->sceneRoot());
+    m_lightGathererJob->setManager(entityManager);
+    m_renderViewJob->setRenderer(m_renderer);
+    m_renderViewJob->setFrameGraphLeafNode(leafNode);
+    m_renderViewJob->setSubmitOrderIndex(m_renderViewIndex);
+
+    // RenderCommand building is the most consuming task -> split it
+    // Estimate the number of jobs to create based on the number of entities
+    m_renderViewBuilderJobs.reserve(RenderViewBuilder::m_optimalParallelJobCount);
+    for (auto i = 0; i < RenderViewBuilder::m_optimalParallelJobCount; ++i) {
+        auto renderViewCommandBuilder = Render::RenderViewBuilderJobPtr::create();
+        renderViewCommandBuilder->setIndex(m_renderViewIndex);
+        renderViewCommandBuilder->setRenderer(m_renderer);
+        m_renderViewBuilderJobs.push_back(renderViewCommandBuilder);
+    }
+
+    // Since Material gathering is an heavy task, we split it
+    const QVector<HMaterial> materialHandles = m_renderer->nodeManagers()->materialManager()->activeHandles();
+    const int elementsPerJob =  materialHandles.size() / RenderViewBuilder::m_optimalParallelJobCount;
+    const int lastRemaingElements = materialHandles.size() % RenderViewBuilder::m_optimalParallelJobCount;
+    m_materialGathererJobs.reserve(RenderViewBuilder::m_optimalParallelJobCount);
+    for (auto i = 0; i < RenderViewBuilder::m_optimalParallelJobCount; ++i) {
+        auto materialGatherer = Render::MaterialParameterGathererJobPtr::create();
+        materialGatherer->setNodeManagers(m_renderer->nodeManagers());
+        materialGatherer->setRenderer(m_renderer);
+        if (i == RenderViewBuilder::m_optimalParallelJobCount - 1)
+            materialGatherer->setHandles(materialHandles.mid(i * elementsPerJob, elementsPerJob + lastRemaingElements));
+        else
+            materialGatherer->setHandles(materialHandles.mid(i * elementsPerJob, elementsPerJob));
+        m_materialGathererJobs.push_back(materialGatherer);
+    }
+
+    m_syncRenderViewInitializationJob = SynchronizerJobPtr::create(SyncRenderViewInitialization(m_renderViewJob,
+                                                                                                m_frustumCullingJob,
+                                                                                                m_filterEntityByLayerJob,
+                                                                                                m_materialGathererJobs,
+                                                                                                m_renderViewBuilderJobs),
+                                                                   JobTypes::SyncRenderViewInitialization);
+
+    m_syncRenderCommandBuildingJob = SynchronizerJobPtr::create(SyncRenderCommandBuilding(m_renderViewJob,
+                                                                                          m_frustumCullingJob,
+                                                                                          m_filterEntityByLayerJob,
+                                                                                          m_lightGathererJob,
+                                                                                          m_renderableEntityFilterJob,
+                                                                                          m_computableEntityFilterJob,
+                                                                                          m_materialGathererJobs,
+                                                                                          m_renderViewBuilderJobs),
+                                                                JobTypes::SyncRenderViewCommandBuilding);
+
+    m_syncRenderViewCommandBuildersJob = SynchronizerJobPtr::create(SyncRenderViewCommandBuilders(m_renderViewJob,
+                                                                                                  m_renderViewBuilderJobs,
+                                                                                                  m_renderer),
+                                                                    JobTypes::SyncRenderViewCommandBuilder);
+}
+
+RenderViewInitializerJobPtr RenderViewBuilder::renderViewJob() const
+{
+    return m_renderViewJob;
+}
+
+FilterLayerEntityJobPtr RenderViewBuilder::filterEntityByLayerJob() const
+{
+    return m_filterEntityByLayerJob;
+}
+
+LightGathererPtr RenderViewBuilder::lightGathererJob() const
+{
+    return m_lightGathererJob;
+}
+
+RenderableEntityFilterPtr RenderViewBuilder::renderableEntityFilterJob() const
+{
+    return m_renderableEntityFilterJob;
+}
+
+ComputableEntityFilterPtr RenderViewBuilder::computableEntityFilterJob() const
+{
+    return m_computableEntityFilterJob;
+}
+
+FrustumCullingJobPtr RenderViewBuilder::frustumCullingJob() const
+{
+    return m_frustumCullingJob;
+}
+
+QVector<RenderViewBuilderJobPtr> RenderViewBuilder::renderViewBuilderJobs() const
+{
+    return m_renderViewBuilderJobs;
+}
+
+QVector<MaterialParameterGathererJobPtr> RenderViewBuilder::materialGathererJobs() const
+{
+    return m_materialGathererJobs;
+}
+
+SynchronizerJobPtr RenderViewBuilder::syncRenderViewInitializationJob() const
+{
+    return m_syncRenderViewInitializationJob;
+}
+
+SynchronizerJobPtr RenderViewBuilder::syncFrustumCullingJob() const
+{
+    return m_syncFrustumCullingJob;
+}
+
+SynchronizerJobPtr RenderViewBuilder::syncRenderCommandBuildingJob() const
+{
+    return m_syncRenderCommandBuildingJob;
+}
+
+SynchronizerJobPtr RenderViewBuilder::syncRenderViewCommandBuildersJob() const
+{
+    return m_syncRenderViewCommandBuildersJob;
+}
+
+SynchronizerJobPtr RenderViewBuilder::setClearDrawBufferIndexJob() const
+{
+    return m_setClearDrawBufferIndexJob;
+}
+
+QVector<Qt3DCore::QAspectJobPtr> RenderViewBuilder::buildJobHierachy() const
+{
+    QVector<Qt3DCore::QAspectJobPtr> jobs;
+
+    jobs.reserve(m_materialGathererJobs.size() + m_renderViewBuilderJobs.size() + 11);
+
+    // Set dependencies
+    m_syncFrustumCullingJob->addDependency(m_renderer->updateWorldTransformJob());
+    m_syncFrustumCullingJob->addDependency(m_renderer->updateShaderDataTransformJob());
+    m_syncFrustumCullingJob->addDependency(m_syncRenderViewInitializationJob);
+
+    m_frustumCullingJob->addDependency(m_renderer->expandBoundingVolumeJob());
+    m_frustumCullingJob->addDependency(m_syncFrustumCullingJob);
+
+    m_setClearDrawBufferIndexJob->addDependency(m_syncRenderViewInitializationJob);
+
+    m_syncRenderViewInitializationJob->addDependency(m_renderViewJob);
+
+    m_filterEntityByLayerJob->addDependency(m_syncRenderViewInitializationJob);
+
+    m_syncRenderCommandBuildingJob->addDependency(m_syncRenderViewInitializationJob);
+    for (const auto materialGatherer : qAsConst(m_materialGathererJobs)) {
+        materialGatherer->addDependency(m_syncRenderViewInitializationJob);
+        m_syncRenderCommandBuildingJob->addDependency(materialGatherer);
+    }
+    m_syncRenderCommandBuildingJob->addDependency(m_renderableEntityFilterJob);
+    m_syncRenderCommandBuildingJob->addDependency(m_computableEntityFilterJob);
+    m_syncRenderCommandBuildingJob->addDependency(m_filterEntityByLayerJob);
+    m_syncRenderCommandBuildingJob->addDependency(m_lightGathererJob);
+    m_syncRenderCommandBuildingJob->addDependency(m_frustumCullingJob);
+
+    for (const auto renderViewCommandBuilder : qAsConst(m_renderViewBuilderJobs)) {
+        renderViewCommandBuilder->addDependency(m_syncRenderCommandBuildingJob);
+        m_syncRenderViewCommandBuildersJob->addDependency(renderViewCommandBuilder);
+    }
+
+    m_renderer->frameCleanupJob()->addDependency(m_syncRenderViewCommandBuildersJob);
+    m_renderer->frameCleanupJob()->addDependency(m_setClearDrawBufferIndexJob);
+
+    // Add jobs
+    jobs.push_back(m_renderViewJob); // Step 1
+    jobs.push_back(m_renderableEntityFilterJob); // Step 1
+    jobs.push_back(m_lightGathererJob); // Step 1
+
+    // Note: do it only if OpenGL 4.3+ available
+    jobs.push_back(m_computableEntityFilterJob); // Step 1
+
+    jobs.push_back(m_syncRenderViewInitializationJob); // Step 2
+
+    jobs.push_back(m_syncFrustumCullingJob); // Step 3
+    jobs.push_back(m_filterEntityByLayerJob); // Step 3
+    jobs.push_back(m_setClearDrawBufferIndexJob); // Step 3
+
+    for (const auto materialGatherer : qAsConst(m_materialGathererJobs)) // Step3
+        jobs.push_back(materialGatherer);
+
+    jobs.push_back(m_frustumCullingJob); // Step 4
+    jobs.push_back(m_syncRenderCommandBuildingJob); // Step 4
+
+    for (const auto renderViewCommandBuilder : qAsConst(m_renderViewBuilderJobs)) // Step 5
+        jobs.push_back(renderViewCommandBuilder);
+
+    jobs.push_back(m_syncRenderViewCommandBuildersJob); // Step 6
+
+    return jobs;
+}
+
+Renderer *RenderViewBuilder::renderer() const
+{
+    return m_renderer;
+}
+
+int RenderViewBuilder::renderViewIndex() const
+{
+    return m_renderViewIndex;
+}
+
+int RenderViewBuilder::optimalJobCount()
+{
+    return RenderViewBuilder::m_optimalParallelJobCount;
+}
+
+void RenderViewBuilder::removeEntitiesNotInSubset(QVector<Entity *> &entities, QVector<Entity *> subset)
+{
+    // Note: assumes entities was sorted already
+    std::sort(subset.begin(), subset.end());
+
+    for (auto i = entities.size() - 1, j = subset.size() - 1; i >= 0; --i) {
+        while (j >= 0 && subset.at(j) > entities.at(i))
+            --j;
+        if (j < 0 || entities.at(i) != subset.at(j))
+            entities.removeAt(i);
+    }
+}
+
+} // Render
+
+} // Qt3DRender
+
+QT_END_NAMESPACE