Changeset 3234

Timestamp:

12/24/08 15:55:54 (16 years ago)

Author:

mattausch

Message:

visibility solution loader for jiris preprocessor
worked on poisson disc sampling

Location:

GTP/trunk/App/Demos/Vis/FriendlyCulling

Files:

• VisibilitySolutionConverter (added)
• VisibilitySolutionConverter/ObjConverter.cpp (added)
• VisibilitySolutionConverter/ObjConverter.h (added)
• VisibilitySolutionConverter/SimpleTri.cpp (added)
• VisibilitySolutionConverter/SimpleTri.h (added)
• VisibilitySolutionConverter/SimpleVec.cpp (added)
• VisibilitySolutionConverter/SimpleVec.h (added)
• VisibilitySolutionConverter/gzstream.cpp (added)
• VisibilitySolutionConverter/gzstream.h (added)
• VisibilitySolutionConverter/main.cpp (added)
• src/SampleGenerator.cpp (modified) (2 diffs)

GTP/trunk/App/Demos/Vis/FriendlyCulling/src/SampleGenerator.cpp

@@ -35 +35 @@
         // this sampling scheme has the benefit that it is hierarchical 
         int maxTries = 1000;
-        const float f_reduction = 0.9f;
+        const float f_reduction = 0.95f;
         
         float r[2];
 
+        // the maximal possible radius: our radius is a fraction of this radius
+        // this is used as a measure of the quality of distribution of the point samples
+        const float rmax = 2.0f * mRadius * sqrt(1.0f / (2.0f * sqrt(3.0f) * mNumSamples));
+
         // generates poisson distribution on disc
-        // start with some threshold
-        // best case: all samples lie on the circumference of circle
+        // start with some thresholds: all samples lie on the circumference of circle
          
-        const float eps = 0.2f;
-        const float minDist = 2.0f * mRadius * M_PI * (1.0f - eps) / (float)mNumSamples;
+        float minDist = 2.0f * rmax;
         float sqrMinDist = minDist * minDist;
 
+        int tries = 0;
+
         //cout << "minDist before= " << minDist << endl;
         Sample2 *s = (Sample2 *)samples;
 
-        int totalTries = 0;
-
         // check if on disc
         for (int i = 0; i < mNumSamples; ++ i)
         {
-                int tries = 0;
-
                 // repeat until valid sample was found
                 while (1)
                 {
-                        ++ tries;
-                        ++ totalTries;
-
-                        // note: should use halton, but seems somewhat broken
-                        mHalton->GetNext(r);
+                        // q: should we use halton or does it conflict with the poisson disc properties?
+                        r[0] = RandomValue(0, 1); r[1] = RandomValue(0, 1);
+                        //mHalton->GetNext(r);
 
                         // scale to -1 .. 1
@@ -99 +97 @@
                         }
 
+                        ++ tries;
+
                         if (tries > maxTries)
                         {
-                                sqrMinDist *= f_reduction;
-                                tries = 0;
+                                minDist *= f_reduction;
+                                sqrMinDist = minDist * minDist;
+
+                                maxTries += 1000;
                         }
                 }
         }
 
-        cout << "minDist after= " << sqrt(sqrMinDist) << " #tries: " << totalTries << endl;
+        cout << "minDist after= " << (float)minDist / mNumSamples<< " #tries: " << tries << endl;
 }