Add QCoreSettings class

Adds the ability to disable bounding volume updates from the core
aspect.

Change-Id: I6d8a4c6f8fd880c9fca015cd40eaf7316747a2c6
Reviewed-by: Paul Lemire <paul.lemire@kdab.com>

2 files changed, 31 insertions, 2 deletions

diff --git a/src/core/jobs/calcboundingvolumejob.cpp b/src/core/jobs/calcboundingvolumejob.cpp
index daab9e35a..4e9339912 100644
--- a/src/core/jobs/calcboundingvolumejob.cpp
+++ b/src/core/jobs/calcboundingvolumejob.cpp
@@ -43,7 +43,9 @@
 #include <Qt3DCore/qboundingvolume.h>
 #include <Qt3DCore/qbuffer.h>
 #include <Qt3DCore/qgeometryview.h>
+#include <Qt3DCore/qcoreaspect.h>
 #include <Qt3DCore/private/job_common_p.h>
+#include <Qt3DCore/private/qcoreaspect_p.h>
 #include <Qt3DCore/private/qaspectjob_p.h>
 #include <Qt3DCore/private/qaspectmanager_p.h>
 #include <Qt3DCore/private/qattribute_p.h>
@@ -203,15 +205,39 @@ BoundingVolumeComputeResult BoundingVolumeComputeData::compute() const
 }
 
 
-CalculateBoundingVolumeJob::CalculateBoundingVolumeJob()
+CalculateBoundingVolumeJob::CalculateBoundingVolumeJob(QCoreAspect *aspect)
     : Qt3DCore::QAspectJob()
+    , m_aspect(aspect)
     , m_root(nullptr)
 {
     SET_JOB_RUN_STAT_TYPE(this, JobTypes::CalcBoundingVolume, 0)
 }
 
+bool CalculateBoundingVolumeJob::isRequired()
+{
+    if (!m_aspect)
+        return true;
+
+    auto daspect = QCoreAspectPrivate::get(m_aspect);
+    return daspect->m_boundingVolumesEnabled;
+}
+
 void CalculateBoundingVolumeJob::run()
 {
+    // There's 2 bounding volume jobs, one here in Core, the other in Render.
+    // - This one computes bounding volumes for entities that have QBoundingVolume
+    //   components and use QGeometryViews.
+    //   In that case the component is updated directly by this job (since core
+    //   aspect does not maintain backend objects for the component)
+    // - The one in render does 2 things:
+    //   . Copy the results of this job to the backend object for entities that
+    //     use QBoundingVolume and QGeometryView (computed results arrive one
+    //     frame later, explicit results arrive on time)
+    //   . Compute the BV for old style QGeometryRenderer which use a QGeometry
+    //     directly without a QGeometryView
+    //
+    // (see more details in Qt3DRender::CalculateBoundingVolumeJob::run)
+
     m_results.clear();
 
     QHash<QEntity *, BoundingVolumeComputeData> dirtyEntities;
diff --git a/src/core/jobs/calcboundingvolumejob_p.h b/src/core/jobs/calcboundingvolumejob_p.h
index 95213df75..b245308ae 100644
--- a/src/core/jobs/calcboundingvolumejob_p.h
+++ b/src/core/jobs/calcboundingvolumejob_p.h
@@ -61,6 +61,7 @@ QT_BEGIN_NAMESPACE
 
 namespace Qt3DCore {
 
+class QCoreAspect;
 class CalculateBoundingVolumeJobPrivate;
 class QEntity;
 class QAttribute;
@@ -96,14 +97,16 @@ struct Q_3DCORE_PRIVATE_EXPORT BoundingVolumeComputeData {
 class Q_3DCORE_PRIVATE_EXPORT CalculateBoundingVolumeJob : public Qt3DCore::QAspectJob
 {
 public:
-    explicit CalculateBoundingVolumeJob();
+    explicit CalculateBoundingVolumeJob(QCoreAspect *aspect);
 
     void setRoot(QEntity *root) { m_root = root; }
+    bool isRequired() override;
     void run() override;
     void postFrame(QAspectEngine *aspectEngine) override;
 
 private:
     Q_DECLARE_PRIVATE(CalculateBoundingVolumeJob)
+    QCoreAspect *m_aspect;
     QEntity *m_root;
     std::vector<BoundingVolumeComputeResult> m_results;
 };