private Vector3 TriangleNormal(Vector3 v0, Vector3 v1, Vector3 v2)
{
var a = RasterVectorUtils.Substract(v1, v0);
var b = RasterVectorUtils.Substract(v2, v0);
return(RasterVectorUtils.Cross(a, b));
}
private void DrawTriangleTrapezoid(
Vector3 topMinInterpolant,
Vector3 deltaMinInterpolant,
Vector3 topMaxInterpolant,
Vector3 deltaMaxInterpolant,
float topMinX,
float deltaMinX,
float topMaxX,
float deltaMaxX,
float minY,
float maxY)
{
int intMinY = Mathf.Clamp(Mathf.CeilToInt(minY), _policyType.MinY, _policyType.MaxY + 1),
intMaxY = Mathf.Clamp(Mathf.CeilToInt(maxY), _policyType.MinY, _policyType.MaxY + 1);
for (int intY = intMinY; intY < intMaxY; intY++)
{
float y = intY - minY,
minX = topMinX + deltaMinX * y,
maxX = topMaxX + deltaMaxX * y;
Vector3 minInterpolant = RasterVectorUtils.Add(topMinInterpolant, RasterVectorUtils.Scale(deltaMinInterpolant, y)),
maxInterpolant = RasterVectorUtils.Add(topMaxInterpolant, RasterVectorUtils.Scale(deltaMaxInterpolant, y));
if (minX > maxX)
{
Exchange(ref minX, ref maxX);
Exchange(ref minInterpolant, ref maxInterpolant);
}
if (maxX > minX)
{
int intMinX = Mathf.Clamp(Mathf.CeilToInt(minX), _policyType.MinX, _policyType.MaxX + 1),
intMaxX = Mathf.Clamp(Mathf.CeilToInt(maxX), _policyType.MinX, _policyType.MaxX + 1);
Vector3 deltaInterpolant = RasterVectorUtils.ScaleInv(RasterVectorUtils.Substract(maxInterpolant, minInterpolant), (maxX - minX));
for (int x = intMinX; x < intMaxX; x++)
{
_policyType.ProcessPixel(x, intY, minInterpolant + deltaInterpolant * (x - minX));
}
}
}
}
public void ProcessPixel(int x, int y, Vector3 worldPosition)
{
if (_volumes.IsInVolume(worldPosition))
{
var cell = _heightsMap[x, y];
if (cell.TriangleIndex != _triangleIndex)
{
// If this is the first hit on this cell from the current triangle, add a new sample
HeightSpan span = new HeightSpan();
var gridPosition = RasterVectorUtils.Add(RasterVectorUtils.Substract(_volumeCenter, _volumeHalfExtent), RasterVectorUtils.Scale(new Vector3(x, 0, y), _cellSize));
span.Range = new Vector2(worldPosition.y, worldPosition.y);
cell.HitTriangles.AddLast(span);
cell.Position = new Vector2(gridPosition.x + _cellSize * 0.5f, gridPosition.z + _cellSize * 0.5f);
cell.TriangleIndex = _triangleIndex;
}
else
{
// If this is not the first hit on this cell from the current triangle, expand the sample min and max
var span = cell.HitTriangles.Last.Value;
span.Range.x = Mathf.Min(span.Range.x, worldPosition.y);
span.Range.y = Mathf.Max(span.Range.y, worldPosition.y);
}
}
}
// Fractions of PrecomputedVisibilitySettings.PlayAreaHeight to guarantee have cell coverage
//private static readonly float[] _testHeights = new float[]{ .4f, .6f, .8f };
public IList <VolumeCell> ComputeVolumeCells(IEnumerable <Collider> allColliders, Func <string, string, float, bool> progress = null)
{
if (_volumes.GetRasterBoundCount() <= 0)
{
return(null);
}
GC.Collect();
_stat.Reset();
OCProfiler.Start();
var startMemory = GC.GetTotalMemory(false);
var allMeshes = new LinkedList <IRasterMesh>();
foreach (var collider in allColliders)
{
allMeshes.AddLast(RasterMeshFactory.CreateRasterMesh(collider));
}
var bounds = _volumes.GetVolumeBounds(_settings.CellSize);
var boundsCenter = bounds.Center;
var boundHalfExtent = bounds.HalfExtent;
var volumeSizes = bounds.HalfExtent * 2.0f / _settings.CellSize;
int sizeX = (int)(volumeSizes.x + DELTA) + 1;
int sizeY = (int)(volumeSizes.z + DELTA) + 1;
var heightsMap = new CellToHeightsMap(sizeX, sizeY);
var rasterPolicy = new CellPlacementRasterPolicy(_settings.CellSize, heightsMap, _volumes);
TriangleRasterizer rasterizer = new TriangleRasterizer(rasterPolicy);
bool cancelled = false;
OCProfiler.Start();
long nextTriangleIndex = 1;
// Rasterize the scene to determine potential cell heights
int meshCount = 0;
Debug.LogFormat("Rasterize Mesh Total Mesh {0}", meshCount);
foreach (var mesh in allMeshes)
{
meshCount++;
if (!Config.IsBatchMode && progress != null)
{
if (progress("体素化", String.Format("当前正在处理Mesh {0}/{1} ...", meshCount, allMeshes.Count),
((float)meshCount) / allMeshes.Count))
{
cancelled = true;
break;
}
}
var meshBounds = mesh.WorldBounds;
// Only process meshes whose bounding box intersects a PVS volume
if (_volumes.Intersect(meshBounds))
{
var triCount = mesh.TriangleCount;
for (int triIndex = 0; triIndex < triCount; ++triIndex)
{
mesh.GetTriangle(triIndex, _triVertices);
var normal = TriangleNormal(_triVertices[0], _triVertices[1], _triVertices[2]);
const float EdgePullback = .1f;
// Only rasterize upward facing triangles
if (normal.y > 0.0f)
{
for (int vertIndex = 0; vertIndex < 3; vertIndex++)
{
// Transform world space positions from [PrecomputedVisibilityBounds.Origin - PrecomputedVisibilityBounds.BoxExtent, PrecomputedVisibilityBounds.Origin + PrecomputedVisibilityBounds.BoxExtent] into [0,1]
Vector3 transformedPosition;
var v = _triVertices[vertIndex];
transformedPosition.x =
(v.x - boundsCenter.x + boundHalfExtent.x) / (2.0f * boundHalfExtent.x);
//transformedPosition.y =
// (v.y - boundsCenter.y + boundHalfExtent.y) / (2.0f * boundHalfExtent.y);
transformedPosition.z =
(v.z - boundsCenter.z + boundHalfExtent.z) / (2.0f * boundHalfExtent.z);
// Project positions onto the XY plane
_XYPositions[vertIndex] = new Vector2(transformedPosition.x * (sizeX - 1), transformedPosition.z * (sizeY - 1));
}
rasterizer.TriangleIndex = nextTriangleIndex;
for (int sampleIndex = 0; sampleIndex < 9; sampleIndex++)
{
var samplePosition = RasterVectorUtils.Add(RasterVectorUtils.Scale(_subsamplePositions[sampleIndex], (1 - 2 * EdgePullback)), new Vector2(EdgePullback, EdgePullback));
rasterizer.DrawTriangle(
_triVertices[0],
_triVertices[1],
_triVertices[2],
RasterVectorUtils.Substract(_XYPositions[0], samplePosition),
RasterVectorUtils.Substract(_XYPositions[1], samplePosition),
RasterVectorUtils.Substract(_XYPositions[2], samplePosition)
);
}
nextTriangleIndex++;
}
}
}
}
_stat.RasterizeTime = OCProfiler.Stop();
if (cancelled)
{
return(null);
}
var cells = new List <VolumeCell>(sizeX * sizeY * 2);
var placedHeightRanges = new List <Vector2>();
Debug.LogFormat("Calculate Cell Total Cells {0}", sizeX * sizeY);
for (int y = 0; y < sizeY; ++y)
{
if (cancelled)
{
break;
}
for (int x = 0; x < sizeX; ++x)
{
if (!Config.IsBatchMode && progress != null)
{
if (progress("计算Cell区域",
String.Format("当前正在处理Cell {0}/{1} ...", x + y * sizeX + 1, sizeX * sizeY),
((float)(x + y * sizeX + 1)) / (sizeX * sizeY)))
{
cancelled = true;
break;
}
}
var cell = heightsMap[x, y];
var currentPosition = cell.Position;
var sortedHitTriangles = cell.HitTriangles.OrderByDescending(span => - span.Range.y).ToList();
float lastSampleHeight = float.NegativeInfinity;
placedHeightRanges.Clear();
OCProfiler.Start();
int count = sortedHitTriangles.Count();
// Pass 1 - only place cells in the largest holes which are most likely to be where the play area is
// Place the bottom slightly above the surface, since cells that clip through the floor often have poor occlusion culling
for (int heightIndex = 0; heightIndex < count; heightIndex++)
{
float currentMaxHeight = sortedHitTriangles[heightIndex].Range.y;
// Place a new cell if this is the highest height
if (heightIndex + 1 == count
// Or if there's a gap above this height of size MinPlayAreaHeight
|| ((sortedHitTriangles[heightIndex + 1].Range.y - currentMaxHeight) > _settings.MinPlayAreaHeight
// And this height is not within a cell that was just placed
&& currentMaxHeight - lastSampleHeight > _settings.MinPlayAreaHeight))
{
var boundsMin = new Vector3(
currentPosition.x - _settings.CellSize * 0.5f,
currentMaxHeight,
currentPosition.y - _settings.CellSize * 0.5f);
var boundsMax = new Vector3(currentPosition.x + _settings.CellSize * 0.5f,
currentMaxHeight + _settings.MaxPlayAreaHeight,
currentPosition.y + _settings.CellSize * 0.5f);
cells.Add(new VolumeCell(boundsMin, boundsMax));
lastSampleHeight = currentMaxHeight;
placedHeightRanges.Add(new Vector2(boundsMin.y, boundsMax.y));
}
}
_stat.Pass1Time += OCProfiler.Stop();
OCProfiler.Start();
// Pass 2 - make sure the space above every triangle is covered by precomputed visibility cells, even if the cells are placed poorly (intersecting the floor)
/*for (int heightIndex = 0; heightIndex < count - 1; heightIndex++)
* {
* for (int extremaIndex = 0; extremaIndex < 2; extremaIndex++)
* {
* var currentMaxHeight = extremaIndex == 0 ? sortedHitTriangles[heightIndex].Range.x : sortedHitTriangles[heightIndex].Range.y;
* var compareHeight = currentMaxHeight + .5f * _settings.MaxPlayAreaHeight;
*
* for (int testIndex = 0; testIndex < 3; testIndex++)
* {
* var testHeight = currentMaxHeight + _testHeights[testIndex] * _settings.MaxPlayAreaHeight;
*
* int closestCellInZIndex = -1;
* float closestCellInZDistance = float.MaxValue;
* bool bInsideCell = false;
*
* for (int placedHeightIndex = 0; placedHeightIndex < placedHeightRanges.Count; placedHeightIndex++)
* {
* var cellHeightRange = placedHeightRanges[placedHeightIndex];
*
* if (testHeight > cellHeightRange.x && testHeight < cellHeightRange.y)
* {
* bInsideCell = true;
* break;
* }
*
* float absDistance = Mathf.Min(Mathf.Abs(compareHeight - cellHeightRange.x), Mathf.Abs(compareHeight - cellHeightRange.y));
*
* if (absDistance < closestCellInZDistance)
* {
* closestCellInZDistance = absDistance;
* closestCellInZIndex = placedHeightIndex;
* }
* }
*
* // Place a cell if TestHeight was not inside any existing cells
* if (!bInsideCell)
* {
* float desiredCellBottom = currentMaxHeight;
*
* if (closestCellInZIndex >= 0)
* {
* var nearestCellHeightRange = placedHeightRanges[closestCellInZIndex];
* var nearestCellCompareHeight = (nearestCellHeightRange.x + nearestCellHeightRange.y) / 2;
*
* // Move the bottom of the cell to be placed such that it doesn't overlap the nearest cell
* // This makes use of the cell's full height to cover space
* if (compareHeight < nearestCellCompareHeight)
* {
* desiredCellBottom = Mathf.Min(desiredCellBottom, nearestCellHeightRange.x - _settings.MaxPlayAreaHeight);
* }
* else if (compareHeight > nearestCellCompareHeight)
* {
* desiredCellBottom = Mathf.Max(desiredCellBottom, nearestCellHeightRange.y);
* }
* }
*
* var boundsMin = new Vector3(
* currentPosition.x - _settings.CellSize * 0.5f,
* desiredCellBottom,
* currentPosition.y - _settings.CellSize * 0.5f);
* var boundsMax = new Vector3(
* currentPosition.x + _settings.CellSize * 0.5f,
* desiredCellBottom + _settings.MaxPlayAreaHeight,
* currentPosition.y + _settings.CellSize * 0.5f);
*
* cells.Add(new VolumeCell(boundsMin, boundsMax));
* placedHeightRanges.Add(new Vector2(boundsMin.y, boundsMax.y));
* }
* }
* }
* }*/
_stat.Pass2Time += OCProfiler.Stop();
}
}
_stat.TotalTime = OCProfiler.Stop();
if (cancelled)
{
return(null);
}
GC.Collect();
_stat.TotalMemory = GC.GetTotalMemory(false) - startMemory;
return(cells);
}
public void DrawTriangle(Vector3 v0, Vector3 v1, Vector3 v2, Vector2 p0, Vector2 p1, Vector2 p2)
{
_interpolants[0] = v0;
_interpolants[1] = v1;
_interpolants[2] = v2;
_points[0] = p0;
_points[1] = p1;
_points[2] = p2;
// Find the top point.
if (_points[1].y < _points[0].y && _points[1].y <= _points[2].y)
{
Exchange(ref _points[0], ref _points[1]);
Exchange(ref _interpolants[0], ref _interpolants[1]);
}
else if (_points[2].y < _points[0].y && _points[2].y <= _points[1].y)
{
Exchange(ref _points[0], ref _points[2]);
Exchange(ref _interpolants[0], ref _interpolants[2]);
}
// Find the bottom point.
if (_points[1].y > _points[2].y)
{
Exchange(ref _points[2], ref _points[1]);
Exchange(ref _interpolants[2], ref _interpolants[1]);
}
// Calculate the edge gradients.
float topMinDiffX = (_points[1].x - _points[0].x) / (_points[1].y - _points[0].y),
topMaxDiffX = (_points[2].x - _points[0].x) / (_points[2].y - _points[0].y);
Vector3 topMinDiffInterpolant = RasterVectorUtils.ScaleInv(RasterVectorUtils.Substract(_interpolants[1], _interpolants[0]), (_points[1].y - _points[0].y)),
topMaxDiffInterpolant = RasterVectorUtils.ScaleInv(RasterVectorUtils.Substract(_interpolants[2], _interpolants[0]), (_points[2].y - _points[0].y));
float bottomMinDiffX = (_points[2].x - _points[1].x) / (_points[2].y - _points[1].y),
bottomMaxDiffX = (_points[2].x - _points[0].x) / (_points[2].y - _points[0].y);
Vector3 bottomMinDiffInterpolant = RasterVectorUtils.ScaleInv(RasterVectorUtils.Substract(_interpolants[2], _interpolants[1]), (_points[2].y - _points[1].y)),
bottomMaxDiffInterpolant = RasterVectorUtils.ScaleInv(RasterVectorUtils.Substract(_interpolants[2], _interpolants[0]), (_points[2].y - _points[0].y));
DrawTriangleTrapezoid(
_interpolants[0],
topMinDiffInterpolant,
_interpolants[0],
topMaxDiffInterpolant,
_points[0].x,
topMinDiffX,
_points[0].x,
topMaxDiffX,
_points[0].y,
_points[1].y
);
DrawTriangleTrapezoid(
_interpolants[1],
bottomMinDiffInterpolant,
RasterVectorUtils.Add(_interpolants[0], RasterVectorUtils.Scale(topMaxDiffInterpolant, (_points[1].y - _points[0].y))),
bottomMaxDiffInterpolant,
_points[1].x,
bottomMinDiffX,
_points[0].x + topMaxDiffX * (_points[1].y - _points[0].y),
bottomMaxDiffX,
_points[1].y,
_points[2].y
);
}