Changeset 2548 for GTP/trunk/Lib/Vis/Preprocessing/src/DifferenceSampling.cpp

Timestamp:

08/22/07 17:35:10 (17 years ago)

Author:

mattausch

Message:

 

File:

• GTP/trunk/Lib/Vis/Preprocessing/src/DifferenceSampling.cpp (modified) (2 diffs)

GTP/trunk/Lib/Vis/Preprocessing/src/DifferenceSampling.cpp

@@ -3 +3 @@
 #include "DifferenceSampling.h"
 #include "ViewCell.h"
+#include "ViewCellsManager.h"
+#include "Preprocessor.h"
 
 
@@ -10 +12 @@
 
 
-
 namespace GtpVisibilityPreprocessor {
 
 
+/** Collects the pvs of the objects which are 
+        in the first but not in the second pvs.
+*/
+static void GetPvsDifference(const ObjectPvs &largerPvs, 
+                                                         const ObjectPvs &smallerPvs, 
+                                                         ObjectContainer &pvsDifference)
+{
+        Intersectable::NewMail();
+        Intersectable *obj;
+
+        ObjectPvsIterator bit = smallerPvs.GetIterator();
+
+        // mail smaller pvs
+        while (bit.HasMoreEntries())
+        {
+                obj = bit.Next();
+                obj->Mail();
+        }
+
+        ObjectPvsIterator ait = largerPvs.GetIterator();
+
+        // write differece pvs
+        while (ait.HasMoreEntries())
+        {
+                obj = ait.Next();
+                pvsDifference.push_back(obj);
+
+                //if (!obj->Mailed())
+                //      c.AddSampleDirty(obj, 0);
+        }
+}
+
+
 DifferenceSampling::DifferenceSampling(Preprocessor &preprocessor):
-SamplingStrategy(preprocessor)
+SamplingStrategy(preprocessor), mCurrentViewCell(0), mNumSamples(0)
 {}
 
 
-void DifferenceSampling::ComputeDifferenceSet(ViewCell *vc, ObjectContainer &differenceSet)
+void DifferenceSampling::ComputeDifferenceSet(ViewCell *vc, 
+                                                                                          ObjectContainer &differenceSet)
 {
+        const ObjectPvs &pvs = vc->GetPvs();
+        const float filterSize = 100;
+        ObjectPvs filteredPvs;
+
+    PvsFilterStatistics pvsStats = mPreprocessor.
+                mViewCellsManager->ApplyFilter2(vc, 
+                                                false, 
+                                                                                filterSize, 
+                                                                                filteredPvs);
+
+        //mDifferencePvs.Clear(false);
+        //mDifferencePvs.Reserve(filteredPvs.GetSize());
+        mPvsDifference.clear();
+        mPvsDifference.reserve(filteredPvs.GetSize());
+
+        GetPvsDifference(filteredPvs, pvs, mPvsDifference);
 }
 
+
+bool DifferenceSampling::GenerateSample(SimpleRay &ray)
+{
+        if (mNumSamples -- <= 0)
+        {
+                ViewCellContainer &viewCells = mPreprocessor.mViewCellsManager->GetViewCells();
+                const int vcIdx = (int)RandomValue(0, (float)viewCells.size() - 0.5f);
+
+                mCurrentViewCell = viewCells[vcIdx];
+
+                ComputeDifferenceSet(mCurrentViewCell, mPvsDifference);
+
+                // n samples per object
+                const int n = 50;
+                mNumSamples = mPvsDifference.size() * n;
+        }
+
+        Vector3 origin, direction; 
+        Vector3 point;
+        Vector3 normal, vcnormal;
+
+        // get a new object from the difference set
+        const int objIdx = (int)RandomValue(0, (float)mPvsDifference.size() - 0.5f);
+    Intersectable *object = mPvsDifference[objIdx];
+
+        // cast a ray from the view cells border towards the object
+        object->GetRandomSurfacePoint(point, normal);
+        mCurrentViewCell->GetRandomEdgePoint(origin, vcnormal);
+
+        direction = point - origin;
+
+        // $$ jb the pdf is yet not correct for all sampling methods!
+        const float c = Magnitude(direction);
+
+        if ((c <= Limits::Small) /*|| (DotProd(direction, normal) < 0)*/)
+        {
+                return false;
+        }
+
+        // $$ jb the pdf is yet not correct for all sampling methods!
+        const float pdf = 1.0f;
+        //cout << "p: " << point << " ";
+        direction *= 1.0f / c;
+        ray = SimpleRay(origin, direction, DIFFERENCE_SAMPLING_BASED_DISTRIBUTION, pdf);
+
+        //cout << "ray: " << ray.mOrigin << " " << ray.mDirection << endl;
+
+        return true;
 }
+
+
+}