public VoxelizationOutput Voxelize(VoxelizationInput input, Action<VoxelizationProgress> progress)
{
// Setup VBO state
GL.EnableClientState(ArrayCap.VertexArray);
GL.EnableClientState(ArrayCap.IndexArray);
m_input = input;
VoxelizationOutput output = new VoxelizationOutput();
output.Octree = input.Octree;
VoxelizationProgress vp = new VoxelizationProgress();
vp.Status = "Voxelizing mesh with " + input.Octree.MaxLevels + " subdivision levels";
progress(vp);
GL.PushAttrib(AttribMask.AllAttribBits);
for (int i = 0; i <= input.Octree.MaxLevels; i++)
{
vp.Progress = (i / (input.Octree.MaxLevels + 1.0f));
vp.Status = "Voxelizing octree level " + i;
progress(vp);
RecursiveSolveStatus(input.Octree.Root, i);
}
GL.PopAttrib();
vp.Progress = 1;
vp.Status = "Done voxelizing mesh";
progress(vp);
return output;
}
public static void Run(string[] args)
{
Application.EnableVisualStyles();
Application.SetCompatibleTextRenderingDefault(false);
ProgramOptions options = new ProgramOptions();
string settingPath = Path.Combine(Path.GetDirectoryName(Application.ExecutablePath), "Oxel.Settings.xml");
VoxelizationInput input = VoxelizationInput.Load(settingPath);
if (input == null)
input = new VoxelizationInput();
if (args.Contains("-c"))
{
// Make sure user can see console output
AttachConsole(PARENT_PROCESS_ID);
input.Clone(options);
if (!CommandLineParser.Parse<ProgramOptions>(args, ref options))
return;
options.Clone(input);
}
else
{
CommandLineParser.Parse<VoxelizationInput>(args, ref input);
}
if (options.UseCommandLine)
{
Logger.IsCommandLine = true;
Operations operations = new Operations();
operations.Initialize(input);
operations.Open(options.InputMesh, input.WindingOrder);
WaitHandle waitHandle = operations.GenerateOccluder((VoxelizationProgress vp) => {
string coverage =
String.Format("Volume Coverage : {0,5:0.##}%", (100 * vp.VolumeCoverage)) + " " +
String.Format("Silhouette Coverage : {0,5:0.##}%", (100 * vp.SilhouetteCoverage));
if (!String.IsNullOrEmpty(vp.Status))
Console.WriteLine(vp.Status + "\r\n");
Console.WriteLine(coverage);
}, new Action(() => { }));
waitHandle.WaitOne();
operations.Save(options.OutputMesh);
}
else
{
using (MainWindow window = new MainWindow(input))
{
window.ShowDialog();
}
}
}
public static Mesh Filter(VoxelizationInput input, Mesh mesh)
{
// Remove the top and bottom polygons
if (input.RemoveTop || input.RemoveBottom)
{
Vector3 upAxis, downAxis;
if (input.UpAxis == UpAxis.Y)
{
upAxis = Vector3.UnitY;
downAxis = -Vector3.UnitY;
}
else // if (input.UpAxis == UpAxis.Z)
{
upAxis = Vector3.UnitZ;
downAxis = -Vector3.UnitZ;
}
List<Triangle> filteredTrianlges = new List<Triangle>();
Triangle[] triangles = Triangle.ToTriangleArray(mesh.Indicies, mesh.Vertices);
foreach (Triangle t in triangles)
{
Plane p = t.Plane;
Vector3 normal = t.NormalCounterClockwise();
// Remove all top polygon
if (input.RemoveTop)
{
if (Vector3Ex.AlmostEquals(ref normal, ref upAxis))
continue;
}
// Remove all bottom polygons that are with-in one voxel of the mesh bounds.
if (input.RemoveBottom)
{
if (Vector3Ex.AlmostEquals(ref normal, ref downAxis))
{
Vector3 closestPoint = input.Octree.MeshBounds.ClosestPointOnSurface(t.Center);
float distance = (t.Center - closestPoint).Length;
if (distance <= input.Octree.SmallestVoxelSideLength)
continue;
}
}
filteredTrianlges.Add(t);
}
Triangle.FromTriangleArray(filteredTrianlges, out mesh.Indicies, out mesh.Vertices);
}
return mesh;
}
public MainWindow(VoxelizationInput input)
{
InitializeComponent();
LinkLabel label = new LinkLabel();
label.Text = "Bug/Feature?";
label.BackColor = Color.Transparent;
label.LinkColor = Color.Blue;
label.ActiveLinkColor = Color.Blue;
label.DisabledLinkColor = Color.Blue;
label.VisitedLinkColor = Color.Blue;
label.LinkClicked += (s, e) =>
{
Process.Start("mailto:[email protected]?subject=[Oxel] Bug/Feature");
};
ToolStripControlHost host = new ToolStripControlHost(label);
host.Alignment = ToolStripItemAlignment.Right;
m_menu.SuspendLayout();
m_menu.Items.Add(host);
m_menu.ResumeLayout(true);
m_gl = new GLControl(new GraphicsMode(32, 24, 8));
m_gl.BackColor = System.Drawing.Color.Black;
m_gl.Dock = System.Windows.Forms.DockStyle.Fill;
m_gl.Location = new System.Drawing.Point(0, 0);
m_gl.Name = "m_gl";
m_gl.Size = new System.Drawing.Size(716, 516);
m_gl.TabIndex = 2;
m_gl.VSync = false;
m_gl.Load += new System.EventHandler(this.m_gl_Load);
m_gl.Paint += new System.Windows.Forms.PaintEventHandler(this.m_gl_Paint);
m_gl.KeyPress += new System.Windows.Forms.KeyPressEventHandler(this.m_gl_KeyPress);
m_gl.MouseDown += new System.Windows.Forms.MouseEventHandler(this.m_gl_MouseDown);
m_gl.MouseMove += new System.Windows.Forms.MouseEventHandler(this.m_gl_MouseMove);
m_gl.MouseUp += new System.Windows.Forms.MouseEventHandler(this.m_gl_MouseUp);
m_gl.MouseWheel += new MouseEventHandler(m_gl_MouseWheel);
m_gl.Resize += new System.EventHandler(this.m_gl_Resize);
this.splitContainer1.Panel1.Controls.Add(this.m_gl);
m_operations = new Operations();
m_operations.Initialize(input);
m_propertyGrid.SelectedObject = m_operations.Input;
m_operations.Input.PropertyChanged += new PropertyChangedEventHandler(vp_PropertyChanged);
}
AABBi SimulatedAnnealingFill(VoxelizationInput input, SilhouetteOcclusionValidator sov, VoxelField volume, ref Vector3i densestVoxel, byte fillByte, List<Occluder> currentOccluders)
{
AABBi current = new AABBi(densestVoxel.X, densestVoxel.Y, densestVoxel.Z, densestVoxel.X + 1, densestVoxel.Y + 1, densestVoxel.Z + 1);
AABBi next = new AABBi(0, 0, 0, 0, 0, 0);
int iteration = -1;
List<AABBi> relevantOccluders = GetRelevantOccluders(input, currentOccluders);
List<AABBi> occluders = relevantOccluders.ToList();
occluders.Add(current);
long coverage = MeasureOccluderOcclusion(sov, input, occluders);
double coolignAlpha = 0.999;
double temperature = 400.0;
double epsilon = 0.001;
Random random = new Random(1337);
int maxItterations = 1000;
long delta = 0;
while (temperature > epsilon && iteration < maxItterations)
{
iteration++;
ComputeNext(random, current, next, volume, ref densestVoxel, delta, temperature);
occluders = relevantOccluders.ToList();
occluders.Add(next);
delta = MeasureOccluderOcclusion(sov, input, occluders) - coverage;
if (delta < 0)
{
next.Clone(current);
coverage = delta + coverage;
}
else
{
double probability = random.NextDouble();
if (probability < Math.Exp(-delta / temperature))
{
next.Clone(current);
coverage = delta + coverage;
}
}
temperature *= coolignAlpha;
if (iteration % 400 == 0)
Console.WriteLine(coverage);
}
FillRange(volume,
new Vector3i(current.MinX, current.MinY, current.MinZ),
new Vector3i(current.MaxX, current.MaxY, current.MaxZ),
fillByte);
return current;
}
long MeasureOccluderOcclusion(SilhouetteOcclusionValidator sov, VoxelizationInput input, List<AABBi> occluderBounds)
{
Mesh mesh = BuildMeshFromBoxes(input, occluderBounds);
RenderableMesh renderable = new RenderableMesh(mesh, true);
long sideCoverage, topCoverage;
sov.ComputeCoverage(renderable, input.Octree.MeshBounds, out sideCoverage, out topCoverage);
renderable.Dispose();
return sideCoverage + topCoverage;
}
List<AABBi> GetRelevantOccluders(VoxelizationInput input, List<Occluder> occluders)
{
var occluderBounds =
from occluder in occluders
where occluder.DeltaOcclusion > input.MinimumOcclusion
orderby occluder.DeltaOcclusion descending
select occluder.Bounds;
return occluderBounds.ToList();
}
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;
}
Mesh BuildMeshFromBoxes(VoxelizationInput input, List<AABBi> boxes)
{
// Build the mesh, this will also remove all false triangle loops and collinear point triangles.
Vector3 deltaP = new Vector3((float)input.Octree.SmallestVoxelSideLength, (float)input.Octree.SmallestVoxelSideLength, (float)input.Octree.SmallestVoxelSideLength);
return MeshBuilder.BuildMesh(input.Octree.VoxelBounds, deltaP, boxes);
}
AABBi BruteForceFill(VoxelizationInput input, SilhouetteOcclusionValidator sov, VoxelField voxelField, Vector3i densestVoxel, byte fillByte, List<Occluder> currentOccluders)
{
Object syncroot = new Object();
Int64 largestVolume = 1;
AABBi largestOccluder = new AABBi(densestVoxel.X, densestVoxel.Y, densestVoxel.Z, densestVoxel.X + 1, densestVoxel.Y + 1, densestVoxel.Z + 1);
int MaxTopOccluders = 2000;
List<AABBi> bestOccluders = new List<AABBi>(MaxTopOccluders);
Parallel.For(densestVoxel.Z + 1, voxelField.VoxelSize.Z, max_z =>
{
for (Int32 min_z = densestVoxel.Z; min_z >= 0; --min_z)
{
for (Int32 max_y = densestVoxel.Y + 1; max_y < voxelField.VoxelSize.Y; ++max_y)
{
for (Int32 min_y = densestVoxel.Y; min_y >= 0; --min_y)
{
for (Int32 max_x = densestVoxel.X + 1; max_x < voxelField.VoxelSize.X; ++max_x)
{
for (Int32 min_x = densestVoxel.X; min_x >= 0; --min_x)
{
Int32 dx = max_x - min_x;
Int32 dy = max_y - min_y;
Int32 dz = max_z - min_z;
Int64 volume = dx * dy * dz;
if (TestRangeForFreeSpace(voxelField, new AABBi(min_x, min_y, min_z, max_x, max_y, max_z)))
{
lock (syncroot)
{
if (volume > largestVolume)
{
largestVolume = volume;
largestOccluder = new AABBi(min_x, min_y, min_z, max_x, max_y, max_z);
if (bestOccluders.Count >= MaxTopOccluders)
bestOccluders.RemoveAt(MaxTopOccluders - 1);
bestOccluders.Insert(0, largestOccluder);
}
}
}
else
{
// if we can't expand outward any further there's no point in checking more.
break;
}
}
}
}
}
}
Debug.WriteLine("Checked " + max_z);
});
List<AABBi> relevantOccluders = GetRelevantOccluders(input, currentOccluders);
long bestCoverage = 0;
AABBi bestCoverageVolume = largestOccluder;
foreach (AABBi occluder in bestOccluders)
{
List<AABBi> tempOccluders = relevantOccluders.ToList();
tempOccluders.Add(occluder);
long coverage = MeasureOccluderOcclusion(sov, input, tempOccluders);
if (coverage > bestCoverage)
{
bestCoverage = coverage;
bestCoverageVolume = occluder;
}
}
FillRange(voxelField, bestCoverageVolume, fillByte);
return bestCoverageVolume;
}
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;
}
