Drive ParticleSystem with an animation instead

This will be helpful later, and also keeps the work in the main thread.

Change-Id: Idf4b9e82a40f31a0b70edda731b85b6c853a1dac
Reviewed-on: http://codereview.qt.nokia.com/1909
Reviewed-by: Alan Alpert <alan.alpert@nokia.com>
Reviewed-by: Martin Jones <martin.jones@nokia.com>

4 files changed, 112 insertions, 62 deletions

diff --git a/src/declarative/particles/qsgparticlepainter.cpp b/src/declarative/particles/qsgparticlepainter.cpp
index 7bcaefa66f..4d795999a0 100644
--- a/src/declarative/particles/qsgparticlepainter.cpp
+++ b/src/declarative/particles/qsgparticlepainter.cpp
@@ -105,12 +105,12 @@ void QSGParticlePainter::setSystem(QSGParticleSystem *arg)
 void QSGParticlePainter::load(QSGParticleData* d)
 {
     initialize(d->group, d->index);
-    commit(d->group, d->index);
+    m_pendingCommits << qMakePair<int, int>(d->group, d->index);
 }
 
 void QSGParticlePainter::reload(QSGParticleData* d)
 {
-    commit(d->group, d->index);
+    m_pendingCommits << qMakePair<int, int>(d->group, d->index);
 }
 
 void QSGParticlePainter::reset()
@@ -148,4 +148,12 @@ void QSGParticlePainter::calcSystemOffset(bool resetPending)
         }
     }
 }
+typedef QPair<int,int> intPair;
+void QSGParticlePainter::performPendingCommits()
+{
+    foreach (intPair p, m_pendingCommits)
+        commit(p.first, p.second);
+    m_pendingCommits.clear();
+}
+
 QT_END_NAMESPACE
diff --git a/src/declarative/particles/qsgparticlepainter_p.h b/src/declarative/particles/qsgparticlepainter_p.h
index 9231467bff..08ae3aede8 100644
--- a/src/declarative/particles/qsgparticlepainter_p.h
+++ b/src/declarative/particles/qsgparticlepainter_p.h
@@ -44,6 +44,7 @@
 
 #include <QObject>
 #include <QDebug>
+#include <QPair>
 #include "qsgparticlesystem_p.h"
 
 QT_BEGIN_HEADER
@@ -66,6 +67,7 @@ public:
     void reload(QSGParticleData*);
     void setCount(int c);
     int count();
+    void performPendingCommits();//Called from updatePaintNode
     QSGParticleSystem* system() const
     {
         return m_system;
@@ -93,6 +95,7 @@ void setParticles(QStringList arg)
         emit particlesChanged(arg);
     }
 }
+
 private slots:
     void calcSystemOffset(bool resetPending = false);
 
@@ -104,11 +107,11 @@ protected:
     virtual void reset();
 
     virtual void componentComplete();
-    virtual void initialize(int gIdx, int pIdx){
+    virtual void initialize(int gIdx, int pIdx){//Called from main thread
         Q_UNUSED(gIdx);
         Q_UNUSED(pIdx);
     }
-    virtual void commit(int gIdx, int pIdx){
+    virtual void commit(int gIdx, int pIdx){//Called in Render Thread
         //###If you need to do something on size changed, check m_data size in this? Or we reset you every time?
         Q_UNUSED(gIdx);
         Q_UNUSED(pIdx);
@@ -123,6 +126,7 @@ protected:
 
 private:
     QSGParticleData* m_sentinel;
+    QSet<QPair<int,int> > m_pendingCommits;
     //QVector<QSGParticleData*> m_shadowData;//For when we implement overwrite: false
 };
 
diff --git a/src/declarative/particles/qsgparticlesystem.cpp b/src/declarative/particles/qsgparticlesystem.cpp
index 9ba5c67296..f25172dbda 100644
--- a/src/declarative/particles/qsgparticlesystem.cpp
+++ b/src/declarative/particles/qsgparticlesystem.cpp
@@ -133,7 +133,7 @@ void QSGParticleDataHeap::insert(QSGParticleData* data)
 int QSGParticleDataHeap::top()
 {
     if (m_end == 0)
-        return 1e24;
+        return 1 << 30;
     return m_data[0].time;
 }
 
@@ -658,8 +658,8 @@ void QSGParticleSystem::componentComplete()
 {
     QSGItem::componentComplete();
     m_componentComplete = true;
-    //if (!m_emitters.isEmpty() && !m_particlePainters.isEmpty())
-    reset();
+    m_animation = new QSGParticleSystemAnimation(this);
+    reset();//restarts animation as well
 }
 
 void QSGParticleSystem::reset()//TODO: Needed? Or just in component complete?
@@ -667,6 +667,7 @@ void QSGParticleSystem::reset()//TODO: Needed? Or just in component complete?
     if (!m_componentComplete)
         return;
 
+    m_timeInt = 0;
     //Clear guarded pointers which have been deleted
     int cleared = 0;
     cleared += m_emitters.removeAll(0);
@@ -690,8 +691,10 @@ void QSGParticleSystem::reset()//TODO: Needed? Or just in component complete?
         p->reset();
     }
 
-    m_timeInt = 0;
-    m_timestamp.restart();//TODO: Better placement
+    if (m_animation){
+        m_animation->stop();
+        m_animation->start();
+    }
     m_initialized = true;
 }
 
@@ -831,37 +834,41 @@ void QSGParticleSystem::finishNewDatum(QSGParticleData *pd){
             p->load(pd);
 }
 
-qint64 QSGParticleSystem::systemSync(QSGParticlePainter* p)
+void QSGParticleSystem::updateCurrentTime( int currentTime )
 {
     if (!m_running)
-        return 0;
+        return;
     if (!m_initialized)
-        return 0;//error in initialization
+        return;//error in initialization
+
+    //### Elapsed time never shrinks - may cause problems if left emitting for weeks at a time.
+    qreal dt = m_timeInt / 1000.;
+    m_timeInt = currentTime + m_startTime;
+    qreal time =  m_timeInt / 1000.;
+    dt = time - dt;
+    m_needsReset.clear();
+    if (m_spriteEngine)
+        m_spriteEngine->updateSprites(m_timeInt);
 
-    if (m_syncList.isEmpty() || m_syncList.contains(p)){//Need to advance the simulation
-        m_syncList.clear();
+    foreach (QSGParticleEmitter* emitter, m_emitters)
+        if (emitter)
+            emitter->emitWindow(m_timeInt);
+    foreach (QSGParticleAffector* a, m_affectors)
+        if (a)
+            a->affectSystem(dt);
+    foreach (QSGParticleData* d, m_needsReset)
+        foreach (QSGParticlePainter* p, m_groupData[d->group]->painters)
+            if (p && d)
+                p->reload(d);
+}
 
-        //### Elapsed time never shrinks - may cause problems if left emitting for weeks at a time.
-        qreal dt = m_timeInt / 1000.;
-        m_timeInt = m_timestamp.elapsed() + m_startTime;
-        qreal time =  m_timeInt / 1000.;
-        dt = time - dt;
-        m_needsReset.clear();
-        if (m_spriteEngine)
-            m_spriteEngine->updateSprites(m_timeInt);
-
-        foreach (QSGParticleEmitter* emitter, m_emitters)
-            if (emitter)
-                emitter->emitWindow(m_timeInt);
-        foreach (QSGParticleAffector* a, m_affectors)
-            if (a)
-                a->affectSystem(dt);
-        foreach (QSGParticleData* d, m_needsReset)
-            foreach (QSGParticlePainter* p, m_groupData[d->group]->painters)
-                if (p && d)
-                    p->reload(d);
-    }
-    m_syncList << p;
+int QSGParticleSystem::systemSync(QSGParticlePainter* p)
+{
+    if (!m_running)
+        return 0;
+    if (!m_initialized)
+        return 0;//error in initialization
+    p->performPendingCommits();
     return m_timeInt;
 }
 
diff --git a/src/declarative/particles/qsgparticlesystem_p.h b/src/declarative/particles/qsgparticlesystem_p.h
index 45a860b579..b9729f9ffd 100644
--- a/src/declarative/particles/qsgparticlesystem_p.h
+++ b/src/declarative/particles/qsgparticlesystem_p.h
@@ -49,6 +49,8 @@
 #include <QPointer>
 #include <QSignalMapper>
 #include <QtDeclarative/private/qsgsprite_p.h>
+#include <QAbstractAnimation>
+#include <QtDeclarative/qdeclarative.h>
 
 QT_BEGIN_HEADER
 
@@ -61,6 +63,7 @@ class QSGParticleAffector;
 class QSGParticleEmitter;
 class QSGParticlePainter;
 class QSGParticleData;
+class QSGParticleSystemAnimation;
 class QSGSpriteEngine;
 class QSGSprite;
 
@@ -208,7 +211,6 @@ class QSGParticleSystem : public QSGItem
     Q_OBJECT
     Q_PROPERTY(bool running READ isRunning WRITE setRunning NOTIFY runningChanged)
     Q_PROPERTY(int startTime READ startTime WRITE setStartTime NOTIFY startTimeChanged)
-
     Q_PROPERTY(QDeclarativeListProperty<QSGSprite> particleStates READ particleStates)
 
 public:
@@ -216,42 +218,46 @@ public:
     ~QSGParticleSystem();
     QDeclarativeListProperty<QSGSprite> particleStates();
 
-bool isRunning() const
-{
-    return m_running;
-}
+    //TODO: Hook up running and temporal manipulators to the animation
+    bool isRunning() const
+    {
+        return m_running;
+    }
 
-int startTime() const
-{
-    return m_startTime;
-}
+    int startTime() const
+    {
+        return m_startTime;
+    }
 
-int count(){ return m_particle_count; }
+    int count(){ return m_particle_count; }
 
 signals:
 
-void systemInitialized();
-void runningChanged(bool arg);
+    void systemInitialized();
+    void runningChanged(bool arg);
 
-void startTimeChanged(int arg);
+    void startTimeChanged(int arg);
 
 
 public slots:
-void reset();
-void setRunning(bool arg);
+    void reset();
+    void setRunning(bool arg);
 
 
-void setStartTime(int arg)
-{
-    m_startTime = arg;
-}
+    void setStartTime(int arg)
+    {
+        m_startTime = arg;
+    }
 
-void fastForward(int ms)
-{
-    m_startTime += ms;
-}
+    void fastForward(int ms)
+    {
+        m_startTime += ms;
+    }
+
+    virtual int duration() const { return -1; }
 
 protected:
+    //This one only once per frame (effectively)
     void componentComplete();
 
 private slots:
@@ -268,17 +274,16 @@ public://###but only really for related class usage. Perhaps we should all be fr
     void moveGroups(QSGParticleData *d, int newGIdx);
     int nextSystemIndex();
 
-    //This one only once per frame (effectively)
-    qint64 systemSync(QSGParticlePainter* p);
+    //This one only once per painter per frame
+    int systemSync(QSGParticlePainter* p);
 
-    QElapsedTimer m_timestamp;
     QSet<QSGParticleData*> m_needsReset;
     QVector<QSGParticleData*> m_bySysIdx; //Another reference to the data (data owned by group), but by sysIdx
     QHash<QString, int> m_groupIds;
     QHash<int, QSGParticleGroupData*> m_groupData;
     QSGSpriteEngine* m_spriteEngine;
 
-    qint64 m_timeInt;
+    int m_timeInt;
     bool m_initialized;
 
     void registerParticlePainter(QSGParticlePainter* p);
@@ -303,6 +308,32 @@ private:
 
     QSignalMapper m_painterMapper;
     QSignalMapper m_emitterMapper;
+    friend class QSGParticleSystemAnimation;
+    void updateCurrentTime( int currentTime );
+    QSGParticleSystemAnimation* m_animation;
+};
+
+// Internally, this animation drives all the timing. Painters sync up in their updatePaintNode
+class QSGParticleSystemAnimation : public QAbstractAnimation
+{
+    Q_OBJECT
+public:
+    QSGParticleSystemAnimation(QSGParticleSystem* system)
+        : QAbstractAnimation(static_cast<QObject*>(system)), m_system(system)
+    { }
+protected:
+    virtual void updateCurrentTime( int t )
+    {
+        m_system->updateCurrentTime(t);
+    }
+
+    virtual int duration() const
+    {
+        return -1;
+    }
+
+private:
+    QSGParticleSystem* m_system;
 };