make send only changed bits work better

libraries/voxels/src/VoxelTree.cpp

@@ -1114,14 +1114,12 @@ int VoxelTree::encodeTreeBitstreamRecursion(VoxelNode* node, unsigned char* outp
             return bytesAtThisLevel;
         }
 
-        /** Not ready for production - coming soon.
-        // If we're not in delta sending mode, but the voxel hasn't changed, then we can also bail early...
-        if (!params.deltaViewFrustum && !node->hasChangedSince(params.lastViewFrustumSent - CHANGE_FUDGE)) {
-            printf("not delta sending, and the node hasn't changed, bail early... lastSent=%lld getLastChanged=%lld\n", 
-                params.lastViewFrustumSent, node->getLastChanged());
+        // If we're not in delta sending mode, and we weren't asked to do a force send, and the voxel hasn't changed, 
+        // then we can also bail early and save bits
+        if (!params.forceSendScene && !params.deltaViewFrustum && 
+            !node->hasChangedSince(params.lastViewFrustumSent - CHANGE_FUDGE)) {
             return bytesAtThisLevel;
         }
-        **/
 
         // If the user also asked for occlusion culling, check if this node is occluded, but only if it's not a leaf.
         // leaf occlusion is handled down below when we check child nodes

libraries/voxels/src/VoxelTree.h

@@ -51,7 +51,7 @@ public:
     long                childWasInViewDiscarded;
     int                 boundaryLevelAdjust;
     uint64_t            lastViewFrustumSent;
-
+    bool                forceSendScene;
     CoverageMap*        map;
     
     EncodeBitstreamParams(
@@ -65,7 +65,8 @@ public:
         bool                wantOcclusionCulling= NO_OCCLUSION_CULLING,
         CoverageMap*        map                 = IGNORE_COVERAGE_MAP,
         int                 boundaryLevelAdjust = NO_BOUNDARY_ADJUST,
-        uint64_t            lastViewFrustumSent = IGNORE_LAST_SENT) :
+        uint64_t            lastViewFrustumSent = IGNORE_LAST_SENT,
+        bool                forceSendScene      = true) :
             maxEncodeLevel          (maxEncodeLevel),
             maxLevelReached         (0),
             viewFrustum             (viewFrustum),
@@ -78,6 +79,7 @@ public:
             childWasInViewDiscarded (0),
             boundaryLevelAdjust     (boundaryLevelAdjust),
             lastViewFrustumSent     (lastViewFrustumSent),
+            forceSendScene          (forceSendScene),
             map                     (map)
     {}
 };

voxel-server/src/VoxelNodeData.cpp

@@ -20,6 +20,7 @@ VoxelNodeData::VoxelNodeData(Node* owningNode) :
     _maxLevelReachedInLastSearch(1),
     _lastTimeBagEmpty(0),
     _viewFrustumChanging(false),
+    _viewFrustumJustStoppedChanging(true),
     _currentPacketIsColor(true)
 {
     _voxelPacket = new unsigned char[MAX_VOXEL_PACKET_SIZE];
@@ -69,10 +70,25 @@ bool VoxelNodeData::updateCurrentViewFrustum() {
         _currentViewFrustum.calculate();
         currentViewFrustumChanged = true;
     }
+    
+    // When we first detect that the view stopped changing, we record this.
+    // but we don't change it back to false until we've completely sent this
+    // scene.
+    if (_viewFrustumChanging && !currentViewFrustumChanged) {
+        _viewFrustumJustStoppedChanging = true;
+    }
     _viewFrustumChanging = currentViewFrustumChanged;
     return currentViewFrustumChanged;
 }
 
+void VoxelNodeData::setViewSent(bool viewSent) { 
+    _viewSent = viewSent; 
+    if (viewSent) {
+        _viewFrustumJustStoppedChanging = false;
+    }
+}
+
+
 void VoxelNodeData::updateLastKnownViewFrustum() {
     bool frustumChanges = !_lastKnownViewFrustum.matches(_currentViewFrustum);
     

voxel-server/src/VoxelNodeData.h

@@ -48,7 +48,11 @@ public:
     void updateLastKnownViewFrustum();
 
     bool getViewSent() const        { return _viewSent; };
-    void setViewSent(bool viewSent) { _viewSent = viewSent; }
+    void setViewSent(bool viewSent);
+
+    bool getViewFrustumChanging()            const { return _viewFrustumChanging;            };
+    bool getViewFrustumJustStoppedChanging() const { return _viewFrustumJustStoppedChanging; };
+    
 
     uint64_t  getLastTimeBagEmpty() const                      { return _lastTimeBagEmpty; };
     void      setLastTimeBagEmpty(uint64_t lastTimeBagEmpty)  { _lastTimeBagEmpty = lastTimeBagEmpty; };
@@ -69,6 +73,7 @@ private:
     ViewFrustum _lastKnownViewFrustum;
     uint64_t _lastTimeBagEmpty;
     bool _viewFrustumChanging;
+    bool _viewFrustumJustStoppedChanging;
     bool _currentPacketIsColor;
 };
 

voxel-server/src/main.cpp

@@ -205,6 +205,7 @@ void deepestLevelVoxelDistributor(NodeList* nodeList,
             }
         }
 
+        // This is the start of "resending" the scene.
         nodeData->nodeBag.insert(serverTree.rootNode);
     }
 
@@ -242,15 +243,12 @@ void deepestLevelVoxelDistributor(NodeList* nodeList,
                 EncodeBitstreamParams params(INT_MAX, &nodeData->getCurrentViewFrustum(), wantColor, 
                                              WANT_EXISTS_BITS, DONT_CHOP, wantDelta, lastViewFrustum,
                                              wantOcclusionCulling, coverageMap, boundaryLevelAdjust,
-                                             nodeData->getLastTimeBagEmpty());
-
+                                             nodeData->getLastTimeBagEmpty(),
+                                             nodeData->getViewFrustumJustStoppedChanging());
+                                             
                 bytesWritten = serverTree.encodeTreeBitstream(subTree, &tempOutputBuffer[0], MAX_VOXEL_PACKET_SIZE - 1,
                                                               nodeData->nodeBag, params);
 
-                if (::debugVoxelSending && wantDelta) {
-                    printf("encodeTreeBitstream() childWasInViewDiscarded=%ld\n", params.childWasInViewDiscarded);
-                }
-                
                 if (nodeData->getAvailable() >= bytesWritten) {
                     nodeData->writeToPacket(&tempOutputBuffer[0], bytesWritten);
                 } else {