prof: Write out frame timings from time to time

Every 120 frames atm. This becomes more interesting once
timestamp queries are implemented...

src/rhi/qrhid3d11.cpp

@@ -582,6 +582,10 @@ QRhi::FrameOpResult QRhiD3D11::endFrame(QRhiSwapChain *swapChain)
 
     swapChainD->currentFrameSlot = (swapChainD->currentFrameSlot + 1) % QD3D11SwapChain::BUFFER_COUNT;
     swapChainD->frameCount += 1;
+
+    QRhiProfilerPrivate *rhiP = profilerPrivateOrNull();
+    QRHI_PROF_F(endSwapChainFrame(swapChain, swapChainD->frameCount));
+
     contextState.currentSwapChain = nullptr;
 
     return QRhi::FrameOpSuccess;

src/rhi/qrhigles2.cpp

@@ -524,14 +524,18 @@ QRhi::FrameOpResult QRhiGles2::endFrame(QRhiSwapChain *swapChain)
 
     executeCommandBuffer(&swapChainD->cb);
 
-    swapChainD->frameCount += 1;
-    currentSwapChain = nullptr;
-
     if (swapChainD->surface) {
         ctx->swapBuffers(swapChainD->surface);
         buffersSwapped = true;
     }
 
+    swapChainD->frameCount += 1;
+
+    QRhiProfilerPrivate *rhiP = profilerPrivateOrNull();
+    QRHI_PROF_F(endSwapChainFrame(swapChain, swapChainD->frameCount));
+
+    currentSwapChain = nullptr;
+
     return QRhi::FrameOpSuccess;
 }
 

src/rhi/qrhimetal.mm

@@ -729,6 +729,10 @@ QRhi::FrameOpResult QRhiMetal::endFrame(QRhiSwapChain *swapChain)
 
     swapChainD->currentFrameSlot = (swapChainD->currentFrameSlot + 1) % QMTL_FRAMES_IN_FLIGHT;
     swapChainD->frameCount += 1;
+
+    QRhiProfilerPrivate *rhiP = profilerPrivateOrNull();
+    QRHI_PROF_F(endSwapChainFrame(swapChain, swapChainD->frameCount));
+
     currentSwapChain = nullptr;
 
     return QRhi::FrameOpSuccess;

src/rhi/qrhiprofiler.cpp

@@ -304,6 +304,33 @@ void QRhiProfilerPrivate::releaseSwapChain(QRhiSwapChain *sc)
     writer->endMap();
 }
 
+void QRhiProfilerPrivate::endSwapChainFrame(QRhiSwapChain *sc, int frameCount)
+{
+    if (!swapchains.contains(sc)) {
+        swapchains[sc].t.start();
+        return;
+    }
+
+    Sc &scd(swapchains[sc]);
+    scd.frameDelta[scd.n++] = scd.t.restart();
+    if (scd.n == Sc::FRAME_SAMPLE_SIZE) {
+        scd.n = 0;
+        float totalDelta = 0;
+        for (int i = 0; i < Sc::FRAME_SAMPLE_SIZE; ++i)
+            totalDelta += scd.frameDelta[i];
+        const float avgDelta = totalDelta / Sc::FRAME_SAMPLE_SIZE;
+        if (ensureStream()) {
+            writer->startMap();
+            WRITE_OP(FrameTime);
+            WRITE_TIMESTAMP;
+            WRITE_PAIR(QLatin1String("swapchain"), quint64(quintptr(sc)));
+            WRITE_PAIR(QLatin1String("frames_since_resize"), frameCount);
+            WRITE_PAIR(QLatin1String("avg_ms_between_frames"), avgDelta);
+            writer->endMap();
+        }
+    }
+}
+
 void QRhiProfilerPrivate::vmemStat(int realAllocCount, int subAllocCount, quint32 totalSize, quint32 unusedSize)
 {
     if (!ensureStream())

src/rhi/qrhiprofiler.h

@@ -60,7 +60,8 @@ public:
         ReleaseTextureStagingArea,
         ResizeSwapChain,
         ReleaseSwapChain,
-        VMemAllocStats
+        VMemAllocStats,
+        FrameTime
     };
 
     QRhiProfiler();

src/rhi/qrhiprofiler_p.h

@@ -44,6 +44,7 @@
 #include "qtrhiglobal_p.h"
 #include "qrhiprofiler.h"
 #include <QElapsedTimer>
+#include <QHash>
 
 QT_BEGIN_NAMESPACE
 
@@ -72,6 +73,8 @@ public:
     void resizeSwapChain(QRhiSwapChain *sc, int bufferCount, int msaaBufferCount, int sampleCount);
     void releaseSwapChain(QRhiSwapChain *sc);
 
+    void endSwapChainFrame(QRhiSwapChain *sc, int frameCount);
+
     void vmemStat(int realAllocCount, int subAllocCount, quint32 totalSize, quint32 unusedSize);
 
     bool ensureStream();
@@ -83,8 +86,17 @@ public:
     QCborStreamWriter *writer = nullptr;
     bool active = false;
     QElapsedTimer ts;
+    struct Sc {
+        QElapsedTimer t;
+        int n = 0;
+        static const int FRAME_SAMPLE_SIZE = 120;
+        qint64 frameDelta[FRAME_SAMPLE_SIZE];
+    };
+    QHash<QRhiSwapChain *, Sc> swapchains;
 };
 
+Q_DECLARE_TYPEINFO(QRhiProfilerPrivate::Sc, Q_MOVABLE_TYPE);
+
 QT_END_NAMESPACE
 
 #endif

src/rhi/qrhivulkan.cpp

@@ -1244,6 +1244,10 @@ QRhi::FrameOpResult QRhiVulkan::endWrapperFrame(QRhiSwapChain *swapChain)
     Q_ASSERT(currentSwapChain == swapChainD);
 
     swapChainD->frameCount += 1;
+
+    QRhiProfilerPrivate *rhiP = profilerPrivateOrNull();
+    QRHI_PROF_F(endSwapChainFrame(swapChain, swapChainD->frameCount));
+
     currentSwapChain = nullptr;
 
     return QRhi::FrameOpSuccess;
@@ -1474,6 +1478,10 @@ QRhi::FrameOpResult QRhiVulkan::endNonWrapperFrame(QRhiSwapChain *swapChain)
 
     swapChainD->currentFrameSlot = (swapChainD->currentFrameSlot + 1) % QVK_FRAMES_IN_FLIGHT;
     swapChainD->frameCount += 1;
+
+    QRhiProfilerPrivate *rhiP = profilerPrivateOrNull();
+    QRHI_PROF_F(endSwapChainFrame(swapChain, swapChainD->frameCount));
+
     currentSwapChain = nullptr;
 
     return QRhi::FrameOpSuccess;