Added culling of low intensity lights.

Author: robertosfield

include/vsg/app/RecordTraversal.h

@@ -90,6 +90,9 @@ namespace vsg
         Mask traversalMask = MASK_ALL;
         Mask overrideMask = MASK_OFF;
 
+        /// Light::intensity minimum value for a light to be passed to GPU.
+        float intensityMinimum = 0.00001;
+
         ref_ptr<Instrumentation> instrumentation;
 
         /// Container for CommandBuffers that have been recorded in current frame

src/vsg/app/RecordTraversal.cpp

@@ -366,31 +366,31 @@ void RecordTraversal::apply(const AmbientLight& light)
     CPU_INSTRUMENTATION_L2_O(instrumentation, &light);
 
     //debug("RecordTraversal::apply(AmbientLight) ", light.className());
-    if (_viewDependentState) _viewDependentState->ambientLights.emplace_back(_state->modelviewMatrixStack.top(), &light);
+    if (light.intensity >= intensityMinimum && _viewDependentState) _viewDependentState->ambientLights.emplace_back(_state->modelviewMatrixStack.top(), &light);
 }
 
 void RecordTraversal::apply(const DirectionalLight& light)
 {
     CPU_INSTRUMENTATION_L2_O(instrumentation, &light);
 
     //debug("RecordTraversal::apply(DirectionalLight) ", light.className());
-    if (_viewDependentState) _viewDependentState->directionalLights.emplace_back(_state->modelviewMatrixStack.top(), &light);
+    if (light.intensity >= intensityMinimum && _viewDependentState) _viewDependentState->directionalLights.emplace_back(_state->modelviewMatrixStack.top(), &light);
 }
 
 void RecordTraversal::apply(const PointLight& light)
 {
     CPU_INSTRUMENTATION_L2_O(instrumentation, &light);
 
     //debug("RecordTraversal::apply(PointLight) ", light.className());
-    if (_viewDependentState) _viewDependentState->pointLights.emplace_back(_state->modelviewMatrixStack.top(), &light);
+    if (light.intensity >= intensityMinimum && _viewDependentState) _viewDependentState->pointLights.emplace_back(_state->modelviewMatrixStack.top(), &light);
 }
 
 void RecordTraversal::apply(const SpotLight& light)
 {
     CPU_INSTRUMENTATION_L2_O(instrumentation, &light);
 
     //debug("RecordTraversal::apply(SpotLight) ", light.className());
-    if (_viewDependentState) _viewDependentState->spotLights.emplace_back(_state->modelviewMatrixStack.top(), &light);
+    if (light.intensity >= intensityMinimum && _viewDependentState) _viewDependentState->spotLights.emplace_back(_state->modelviewMatrixStack.top(), &light);
 }
 
 // transform nodes