public virtual VoxelizationOutput Generate(VoxelizationInput input, Action <VoxelizationProgress> progress)
{
VoxelizationProgress vp = new VoxelizationProgress();
DateTime start = DateTime.Now;
vp.Status = "Building voxel field from octree";
progress(vp);
VoxelField voxelField = new VoxelField(input.Octree);
Byte fillByte = 2;
float oldPercent = 1.0f;
float newPercent = 1.0f;
List <Occluder> occluders = new List <Occluder>();
vp.Status = "Calculating original mesh silhouette coverage";
progress(vp);
SilhouetteOcclusionValidator sov = new SilhouetteOcclusionValidator(1024, 1024);
long groundSideCoverage, groundTopCoverage;
sov.ComputeCoverage(input.OriginalMesh, input.Octree.MeshBounds, out groundSideCoverage, out groundTopCoverage);
long totalCoverage = groundSideCoverage + groundTopCoverage;
if (totalCoverage == 0)
{
totalCoverage = 1;
}
vp.Status = "Fitting boxes into mesh...";
progress(vp);
long oldOcclusion = 0;
do
{
Vector3i densestVoxel = FindHighestDensityVoxel(voxelField);
AABBi occluderBounds;
if (input.Type == OcclusionType.BoxExpansion)
{
occluderBounds = ExpandAndFillBox(voxelField, ref densestVoxel, fillByte);
}
//else if (input.Type == OcclusionType.SimulatedAnnealing)
//{
// occluderBounds = SimulatedAnnealingFill(input, sov, voxelField, ref densestVoxel, fillByte, occluders);
//}
else if (input.Type == OcclusionType.BruteForce)
{
occluderBounds = BruteForceFill(input, sov, voxelField, densestVoxel, fillByte, occluders);
}
else
{
throw new Exception("Unknown occluder generation type!");
}
List <AABBi> relevantOccluders = GetRelevantOccluders(input, occluders);
relevantOccluders.Add(occluderBounds);
long newOcclusion = MeasureOccluderOcclusion(sov, input, relevantOccluders);
Occluder occluder = new Occluder();
occluder.Bounds = occluderBounds;
occluder.DeltaOcclusion = (newOcclusion - oldOcclusion) / (double)totalCoverage;
occluders.Add(occluder);
if (occluder.DeltaOcclusion > input.MinimumOcclusion)
{
oldOcclusion = newOcclusion;
}
Debug.WriteLine("Coverage " + occluder.DeltaOcclusion);
Debug.WriteLine("Bounds (" + occluder.Bounds.MinX + "x" + occluder.Bounds.MaxX + " " + occluder.Bounds.MinY + "x" + occluder.Bounds.MaxY + " " + occluder.Bounds.MinZ + "x" + occluder.Bounds.MaxZ + ")");
oldPercent = newPercent;
newPercent = MeasureUnboxedVoxels(voxelField);
Debug.WriteLine("(" + densestVoxel.X + "," + densestVoxel.Y + "," + densestVoxel.Z + ")\tCoverage=" + ((1 - newPercent) * 100) + "%\tDelta=" + ((oldPercent - newPercent) * 100) + "%");
vp.Progress = Math.Min(((1 - newPercent) / input.MinimumVolume), 1.0f);
vp.SilhouetteCoverage = oldOcclusion / (double)totalCoverage;
vp.VolumeCoverage = 1 - newPercent;
vp.Status = String.Format("Occlusion Progress : {0:0.##}%", (100 * vp.Progress));
progress(vp);
} while (newPercent > (1 - input.MinimumVolume));
Mesh mesh = BuildMeshFromBoxes(input, GetRelevantOccluders(input, occluders));
VoxelizationOutput output = new VoxelizationOutput();
if (input.Retriangulate)
{
vp.Status = "Retriangulating occluder mesh";
progress(vp);
Mesh triangulatedMesh = MeshOptimizer.Retriangulate(input, mesh, out output.DebugLines);
if (triangulatedMesh != null)
{
mesh = triangulatedMesh;
}
}
vp.Status = "Filtering polygons";
progress(vp);
mesh = PolygonFilter.Filter(input, mesh);
vp.Status = "Generating final occlusion mesh";
progress(vp);
// Prepare the output
output.Octree = input.Octree;
output.TimeTaken = DateTime.Now - start;
output.VolumeCoverage = 1 - newPercent;
output.SilhouetteCoverage = oldOcclusion / (double)totalCoverage;
output.OccluderMesh = new RenderableMesh(mesh, true);
vp.Status = "Cleanup...";
progress(vp);
sov.Dispose();
return(output);
}
public VoxelizationOutput Generate(VoxelizationInput input, Action <VoxelizationProgress> progress)
{
this.input = input;
VoxelizationOutput output = new VoxelizationOutput();
output.Octree = input.Octree;
List <List <VoxelizingOctreeCell> > cellList = new List <List <VoxelizingOctreeCell> >();
input.Octree.AccumulateChildren(out cellList);
VolumeAccumulator volume = new VolumeAccumulator();
VolumeAccumulator[] volumeAtLevel = new VolumeAccumulator[input.Octree.MaxLevels];
for (int i = 0; i < input.Octree.MaxLevels; i++)
{
List <VoxelizingOctreeCell> childernAtDepth = cellList[i];
VolumeAccumulator levelVolumeTotal = new VolumeAccumulator();
Parallel.For(0, childernAtDepth.Count, () => new VolumeAccumulator(), (n, loop, partial) =>
{
VoxelizingOctreeCell cell = childernAtDepth[n];
float sideLength = cell.Length;
switch (cell.Status)
{
case CellStatus.Inside:
partial.InsideTotal += (sideLength * sideLength * sideLength);
break;
case CellStatus.Outside:
partial.OutsideTotal += (sideLength * sideLength * sideLength);
break;
case CellStatus.Intersecting:
case CellStatus.IntersectingBounds:
if (cell.IsLeaf)
{
partial.IntersectingTotal += (sideLength * sideLength * sideLength);
}
break;
}
return(partial);
},
partial =>
{
lock (levelVolumeTotal)
{
levelVolumeTotal.InsideTotal += partial.InsideTotal;
levelVolumeTotal.OutsideTotal += partial.OutsideTotal;
levelVolumeTotal.IntersectingTotal += partial.IntersectingTotal;
}
});
volume.InsideTotal += levelVolumeTotal.InsideTotal;
volume.OutsideTotal += levelVolumeTotal.OutsideTotal;
volume.IntersectingTotal += levelVolumeTotal.IntersectingTotal;
volumeAtLevel[i] = levelVolumeTotal;
}
Debug.WriteLine("Percentage of inner volume at each octree level");
for (int i = 0; i < input.Octree.MaxLevels; i++)
{
Debug.WriteLine("Level {0}: Inner Volume {1}%", i, (volumeAtLevel[i].InsideTotal / volume.InsideTotal) * 100);
}
// A good check to perform is to compare the ratio of intersecting volume leaf nodes to the total volume
// we've determined is inside. A tool could use this ratio to automatically determine a good octree level
// by iterative optimization. If a mesh for example fails to get at least a 1 : 0.5 ratio of intersecting:inner
// volume ratio it's a good bet that the octree does not subdivide enough levels in order to find enough inner volume
// to meet our occlusion needs. If further subdivision up to some maximum, lets say 8 fails to ever meet this ratio
// one could say the mesh is not a good candidate for automating occluder generation.
Debug.WriteLine("");
float intersecting_inside_ratio = volume.InsideTotal / volume.IntersectingTotal;
Debug.WriteLine("Intersecting : Inner = 1:{0}", intersecting_inside_ratio);
Debug.WriteLine("Inner / (Inner + Intersecting) = {0}", volume.InsideTotal / (volume.InsideTotal + volume.IntersectingTotal));
const float MINIMUM_INTERSECTING_TO_INSIDE_RATIO = 0.25f;
AABBf meshBounds = input.Octree.MeshBounds;
double dX = meshBounds.MaxX - meshBounds.MinX;
double dY = meshBounds.MaxY - meshBounds.MinY;
double dZ = meshBounds.MaxZ - meshBounds.MinZ;
double reduction = 0.5;
for (int i = 0; i <= input.Octree.MaxLevels * 2; i++)
{
reduction *= 0.5;
}
dX = dX * reduction;
dY = dY * reduction;
dZ = dZ * reduction;
if (intersecting_inside_ratio > MINIMUM_INTERSECTING_TO_INSIDE_RATIO)
{
List <AABBi> innerBounds = new List <AABBi>();
float innerVolumeGathered = 0.0f;
for (int i = 0; i < input.Octree.MaxLevels; i++)
{
for (int n = 0; n < cellList[i].Count; n++)
{
if (cellList[i][n].Status == CellStatus.Inside)
{
AABBf bound = cellList[i][n].Bounds;
AABBi bi = new AABBi();
bi.MaxX = (int)Math.Round(((double)bound.MaxX - (double)meshBounds.MinX) / dX, MidpointRounding.AwayFromZero);
bi.MaxY = (int)Math.Round(((double)bound.MaxY - (double)meshBounds.MinY) / dY, MidpointRounding.AwayFromZero);
bi.MaxZ = (int)Math.Round(((double)bound.MaxZ - (double)meshBounds.MinZ) / dZ, MidpointRounding.AwayFromZero);
bi.MinX = (int)Math.Round(((double)bound.MinX - (double)meshBounds.MinX) / dX, MidpointRounding.AwayFromZero);
bi.MinY = (int)Math.Round(((double)bound.MinY - (double)meshBounds.MinY) / dY, MidpointRounding.AwayFromZero);
bi.MinZ = (int)Math.Round(((double)bound.MinZ - (double)meshBounds.MinZ) / dZ, MidpointRounding.AwayFromZero);
innerBounds.Add(bi);
}
}
innerVolumeGathered += volumeAtLevel[i].InsideTotal / volume.InsideTotal;
if (innerVolumeGathered > input.MinimumVolume)
{
break;
}
}
Debug.WriteLine("Enough inner volume found {0}%", innerVolumeGathered * 100.0f);
Mesh mesh = MeshBuilder.BuildMesh(innerBounds);
for (int i = 0; i < mesh.Vertices.Length; i++)
{
mesh.Vertices[i].X = (float)(((double)meshBounds.MinX) + (mesh.Vertices[i].X * dX));
mesh.Vertices[i].Y = (float)(((double)meshBounds.MinY) + (mesh.Vertices[i].Y * dY));
mesh.Vertices[i].Z = (float)(((double)meshBounds.MinZ) + (mesh.Vertices[i].Z * dZ));
}
if (input.Retriangulate)
{
Mesh triangulatedMesh = MeshOptimizer.Retriangulate(input, mesh, out output.DebugLines);
if (triangulatedMesh != null)
{
mesh = triangulatedMesh;
}
}
mesh = PolygonFilter.Filter(input, mesh);
output.OccluderMesh = new RenderableMesh(mesh, true);
}
else
{
Debug.WriteLine("Not enough inner volume found to continue.");
}
return(output);
}