public static unsafe BlobAssetReference <Collider> Create(NativeArray <float3> vertices, NativeArray <int3> triangles, CollisionFilter filter, Material material)
{
// Copy vertices
var tempVertices = new NativeArray <float3>(vertices, Allocator.Temp);
// Triangle indices - needed for WeldVertices
var tempIndices = new NativeArray <int>(triangles.Length * 3, Allocator.Temp);
for (int iTriangle = 0; iTriangle < triangles.Length; iTriangle++)
{
if (triangles[iTriangle][0] >= 0 && triangles[iTriangle][0] < vertices.Length &&
triangles[iTriangle][1] >= 0 && triangles[iTriangle][1] < vertices.Length &&
triangles[iTriangle][2] >= 0 && triangles[iTriangle][2] < vertices.Length)
{
tempIndices[iTriangle * 3] = triangles[iTriangle][0];
tempIndices[iTriangle * 3 + 1] = triangles[iTriangle][1];
tempIndices[iTriangle * 3 + 2] = triangles[iTriangle][2];
}
else
{
throw new ArgumentException("Tried to create a MeshCollider with indices referencing outside vertex array");
}
}
// Build connectivity and primitives
NativeList <float3> uniqueVertices = MeshConnectivityBuilder.WeldVertices(tempIndices, tempVertices);
var tempTriangleIndices = new NativeArray <int3>(triangles.Length, Allocator.Temp);
UnsafeUtility.MemCpy(tempTriangleIndices.GetUnsafePtr(), tempIndices.GetUnsafePtr(), tempIndices.Length * UnsafeUtility.SizeOf <int>());
var connectivity = new MeshConnectivityBuilder(tempTriangleIndices, uniqueVertices);
NativeList <MeshConnectivityBuilder.Primitive> primitives = connectivity.EnumerateQuadDominantGeometry(tempTriangleIndices, uniqueVertices);
// Build bounding volume hierarchy
int nodeCount = math.max(primitives.Length * 2 + 1, 2); // We need at least two nodes - an "invalid" node and a root node.
var nodes = new NativeArray <BoundingVolumeHierarchy.Node>(nodeCount, Allocator.Temp);
int numNodes = 0;
{
// Prepare data for BVH
var points = new NativeList <BoundingVolumeHierarchy.PointAndIndex>(primitives.Length, Allocator.Temp);
var aabbs = new NativeArray <Aabb>(primitives.Length, Allocator.Temp);
for (int i = 0; i < primitives.Length; i++)
{
MeshConnectivityBuilder.Primitive p = primitives[i];
// Skip degenerate triangles
if (MeshConnectivityBuilder.IsTriangleDegenerate(p.Vertices[0], p.Vertices[1], p.Vertices[2]))
{
continue;
}
aabbs[i] = Aabb.CreateFromPoints(p.Vertices);
points.Add(new BoundingVolumeHierarchy.PointAndIndex
{
Position = aabbs[i].Center,
Index = i
});
}
var bvh = new BoundingVolumeHierarchy(nodes);
bvh.Build(points.AsArray(), aabbs, out numNodes, useSah: true);
}
// Build mesh sections
BoundingVolumeHierarchy.Node *nodesPtr = (BoundingVolumeHierarchy.Node *)nodes.GetUnsafePtr();
MeshBuilder.TempSection sections = MeshBuilder.BuildSections(nodesPtr, numNodes, primitives);
// Allocate collider
int meshDataSize = Mesh.CalculateMeshDataSize(numNodes, sections.Ranges);
int totalColliderSize = Math.NextMultipleOf(sizeof(MeshCollider), 16) + meshDataSize;
MeshCollider *meshCollider = (MeshCollider *)UnsafeUtility.Malloc(totalColliderSize, 16, Allocator.Temp);
// Initialize it
{
UnsafeUtility.MemClear(meshCollider, totalColliderSize);
meshCollider->MemorySize = totalColliderSize;
meshCollider->m_Header.Type = ColliderType.Mesh;
meshCollider->m_Header.CollisionType = CollisionType.Composite;
meshCollider->m_Header.Version += 1;
meshCollider->m_Header.Magic = 0xff;
ref var mesh = ref meshCollider->Mesh;
mesh.Init(nodesPtr, numNodes, sections, filter, material);
// Calculate combined filter
meshCollider->m_Header.Filter = mesh.Sections.Length > 0 ? mesh.Sections[0].Filters[0] : CollisionFilter.Default;
for (int i = 0; i < mesh.Sections.Length; ++i)
{
for (var j = 0; j < mesh.Sections[i].Filters.Length; ++j)
{
var f = mesh.Sections[i].Filters[j];
meshCollider->m_Header.Filter = CollisionFilter.CreateUnion(meshCollider->m_Header.Filter, f);
}
}
meshCollider->m_Aabb = meshCollider->Mesh.BoundingVolumeHierarchy.Domain;
meshCollider->NumColliderKeyBits = meshCollider->Mesh.NumColliderKeyBits;
}
internal static unsafe List <TempSection> BuildSections(BoundingVolumeHierarchy.Node *nodes, int nodeCount, List <MeshConnectivityBuilder.Primitive> primitives)
{
var tempSections = new List <TempSection>();
// Traverse the tree and break out geometry into sections
int *nodesIndexStack = stackalloc int[BoundingVolumeHierarchy.Constants.UnaryStackSize];
int stackSize = 1;
nodesIndexStack[0] = 1;
const float uniqueVerticesPerPrimitiveFactor = 1.5f;
int[] primitivesCountInSubTree = ProducedPrimitivesCountPerSubTree(nodes, nodeCount);
do
{
int nodeIndex = nodesIndexStack[--stackSize];
int subTreeVertexCountEstimate = (int)(uniqueVerticesPerPrimitiveFactor * primitivesCountInSubTree[nodeIndex]);
var subTreeIndices = new List <int>();
if (subTreeVertexCountEstimate < Mesh.Section.MaxNumVertices)
{
subTreeIndices.Add(nodeIndex);
}
else
{
// Sub tree is too big, break it up.
BoundingVolumeHierarchy.Node node = nodes[nodeIndex];
for (int i = 0; i < 4; i++)
{
if (node.IsChildValid(i))
{
int childNodeIndex = node.Data[i];
int nodeSubTreeVertexCount = (int)(uniqueVerticesPerPrimitiveFactor * primitivesCountInSubTree[childNodeIndex]);
if (nodeSubTreeVertexCount < Mesh.Section.MaxNumVertices)
{
subTreeIndices.Add(childNodeIndex);
}
else
{
nodesIndexStack[stackSize++] = childNodeIndex;
}
}
}
}
float tempUniqueVertexPrimitiveFactor = 1.0f;
const float factorStepIncrement = 0.25f;
while (subTreeIndices.Any())
{
// Try to combine sub trees if multiple sub trees can fit into one section.
var nodeIndices = new List <int>();
int vertexCountEstimate = 0;
foreach (int subTreeNodeIndex in subTreeIndices)
{
int nodeIndexCount = (int)(tempUniqueVertexPrimitiveFactor * primitivesCountInSubTree[subTreeNodeIndex]);
if (vertexCountEstimate + nodeIndexCount < Mesh.Section.MaxNumVertices)
{
vertexCountEstimate += nodeIndexCount;
nodeIndices.Add(subTreeNodeIndex);
}
}
if (!nodeIndices.Any())
{
// We failed to fit any sub tree into sections.
// Split up nodes and push them to stack.
foreach (int subTreeNodeIndex in subTreeIndices)
{
BoundingVolumeHierarchy.Node nodeToSplit = nodes[subTreeNodeIndex];
for (int i = 0; i < 4; i++)
{
if (nodeToSplit.IsChildValid(i))
{
nodesIndexStack[stackSize++] = nodeToSplit.Data[i];
}
}
}
subTreeIndices.Clear();
continue;
}
// Collect vertices from all sub trees.
var tmpVertices = new List <float3>();
foreach (int subTreeNodeIndex in nodeIndices)
{
tmpVertices.AddRange(CollectAllVerticesFromSubTree(nodes, subTreeNodeIndex, primitives));
}
float3[] allVertices = tmpVertices.ToArray();
int[] vertexIndices = new int[allVertices.Length];
for (int i = 0; i < vertexIndices.Length; i++)
{
vertexIndices[i] = i;
}
MeshConnectivityBuilder.WeldVertices(vertexIndices, ref allVertices);
if (allVertices.Length < Mesh.Section.MaxNumVertices)
{
tempSections.Add(BuildSectionGeometry(tempSections.Count, primitives, nodeIndices, nodes, allVertices));
// Remove used indices
foreach (int nodeTreeIndex in nodeIndices)
{
subTreeIndices.Remove(nodeTreeIndex);
}
}
else
{
// Estimate of num vertices per primitives was wrong.
// Increase the tempUniqueVertexPrimitiveFactor.
tempUniqueVertexPrimitiveFactor += factorStepIncrement;
}
}
}while (stackSize > 0);
return(tempSections);
}
internal static unsafe TempSection BuildSections(BoundingVolumeHierarchy.Node *nodes, int nodeCount, NativeList <MeshConnectivityBuilder.Primitive> primitives)
{
var tempSections = new TempSection()
{
PrimitivesFlags = new NativeList <Mesh.PrimitiveFlags>(Allocator.Temp),
Primitives = new NativeList <Mesh.PrimitiveVertexIndices>(Allocator.Temp),
Vertices = new NativeList <float3>(Allocator.Temp),
Ranges = new NativeList <TempSectionRanges>(Allocator.Temp)
};
if (primitives.Length == 0)
{
// Early-out in the case of no input primitives
return(tempSections);
}
// Traverse the tree and break out geometry into sections
int *nodesIndexStack = stackalloc int[BoundingVolumeHierarchy.Constants.UnaryStackSize];
int stackSize = 1;
nodesIndexStack[0] = 1;
const float uniqueVerticesPerPrimitiveFactor = 1.5f;
var primitivesCountInSubTree = ProducedPrimitivesCountPerSubTree(nodes, nodeCount);
var subTreeIndices = new NativeList <int>(Allocator.Temp);
var nodeIndices = new NativeList <int>(Allocator.Temp);
var tmpVertices = new NativeList <float3>(Allocator.Temp);
do
{
int nodeIndex = nodesIndexStack[--stackSize];
int subTreeVertexCountEstimate = (int)(uniqueVerticesPerPrimitiveFactor * primitivesCountInSubTree[nodeIndex]);
subTreeIndices.Clear();
if (subTreeVertexCountEstimate < Mesh.Section.MaxNumVertices)
{
subTreeIndices.Add(nodeIndex);
}
else
{
// Sub tree is too big, break it up.
BoundingVolumeHierarchy.Node node = nodes[nodeIndex];
for (int i = 0; i < 4; i++)
{
if (node.IsChildValid(i))
{
int childNodeIndex = node.Data[i];
int nodeSubTreeVertexCount = (int)(uniqueVerticesPerPrimitiveFactor * primitivesCountInSubTree[childNodeIndex]);
if (nodeSubTreeVertexCount < Mesh.Section.MaxNumVertices)
{
subTreeIndices.Add(childNodeIndex);
}
else
{
nodesIndexStack[stackSize++] = childNodeIndex;
}
}
}
}
float tempUniqueVertexPrimitiveFactor = 1.0f;
const float factorStepIncrement = 0.25f;
while (subTreeIndices.Length > 0)
{
// Try to combine sub trees if multiple sub trees can fit into one section.
nodeIndices.Clear();
int vertexCountEstimate = 0;
for (var i = 0; i < subTreeIndices.Length; ++i)
{
var subTreeNodeIndex = subTreeIndices[i];
int nodeIndexCount = (int)(tempUniqueVertexPrimitiveFactor * primitivesCountInSubTree[subTreeNodeIndex]);
if (vertexCountEstimate + nodeIndexCount < Mesh.Section.MaxNumVertices)
{
vertexCountEstimate += nodeIndexCount;
nodeIndices.Add(subTreeNodeIndex);
}
}
if (nodeIndices.Length == 0)
{
// We failed to fit any sub tree into sections.
// Split up nodes and push them to stack.
for (var index = 0; index < subTreeIndices.Length; ++index)
{
var subTreeNodeIndex = subTreeIndices[index];
BoundingVolumeHierarchy.Node nodeToSplit = nodes[subTreeNodeIndex];
for (int i = 0; i < 4; i++)
{
if (nodeToSplit.IsChildValid(i))
{
nodesIndexStack[stackSize++] = nodeToSplit.Data[i];
}
}
}
subTreeIndices.Clear();
continue;
}
// Collect vertices from all sub trees.
tmpVertices.Clear();
for (var i = 0; i < nodeIndices.Length; ++i)
{
var subTreeNodeIndex = nodeIndices[i];
CollectAllVerticesFromSubTree(nodes, subTreeNodeIndex, primitives, tmpVertices);
}
var vertexIndices = new NativeArray <int>(tmpVertices.Length, Allocator.Temp);
for (int i = 0; i < vertexIndices.Length; i++)
{
vertexIndices[i] = i;
}
NativeList <float3> uniqueVertices = MeshConnectivityBuilder.WeldVertices(vertexIndices, new NativeArray <float3>(tmpVertices, Allocator.Temp));
if (uniqueVertices.Length < Mesh.Section.MaxNumVertices)
{
BuildSectionGeometry(tempSections, primitives, nodeIndices, nodes, new NativeArray <float3>(uniqueVertices, Allocator.Temp));
// Remove used indices
for (var i = 0; i < nodeIndices.Length; ++i)
{
var nodeTreeIndex = nodeIndices[i];
subTreeIndices.RemoveAtSwapBack(subTreeIndices.IndexOf(nodeTreeIndex));
}
}
else
{
// Estimate of num vertices per primitives was wrong.
// Increase the tempUniqueVertexPrimitiveFactor.
tempUniqueVertexPrimitiveFactor += factorStepIncrement;
}
}
}while (stackSize > 0);
return(tempSections);
}
// followed by variable sized mesh data
#region Construction
// Create a mesh collider asset from a set of triangles
public static unsafe BlobAssetReference <Collider> Create(float3[] vertices, int[] indices, CollisionFilter?filter = null, Material?material = null)
{
int numVertices = vertices.Length;
int numIndices = indices.Length;
int numTriangles = numIndices / 3;
// Copy vertices
float3[] tempVertices = new float3[numVertices];
Array.Copy(vertices, tempVertices, numVertices);
// Copy indices
int[] tempIndices = new int[numIndices];
for (int iTriangle = 0; iTriangle < numTriangles; iTriangle++)
{
int iIndex0 = iTriangle * 3;
int iIndex1 = iIndex0 + 1;
int iIndex2 = iIndex0 + 2;
tempIndices[iIndex0] = indices[iIndex0];
tempIndices[iIndex1] = indices[iIndex1];
tempIndices[iIndex2] = indices[iIndex2];
}
// Build connectivity and primitives
List <MeshConnectivityBuilder.Primitive> primitives = null;
{
MeshConnectivityBuilder.WeldVertices(tempIndices, ref tempVertices);
var connectivity = new MeshConnectivityBuilder(tempIndices, tempVertices);
primitives = connectivity.EnumerateQuadDominantGeometry(tempIndices, tempVertices);
}
// Build bounding volume hierarchy
var nodes = new NativeArray <BoundingVolumeHierarchy.Node>(primitives.Count * 2 + 1, Allocator.Temp);
int numNodes = 0;
{
// Prepare data for BVH
var points = new NativeArray <BoundingVolumeHierarchy.PointAndIndex>(primitives.Count, Allocator.Temp);
var aabbs = new NativeArray <Aabb>(primitives.Count, Allocator.Temp);
for (int i = 0; i < primitives.Count; i++)
{
MeshConnectivityBuilder.Primitive p = primitives[i];
// Skip degenerate triangles
if (MeshConnectivityBuilder.IsTriangleDegenerate(p.Vertices[0], p.Vertices[1], p.Vertices[2]))
{
continue;
}
aabbs[i] = Aabb.CreateFromPoints(p.Vertices);
points[i] = new BoundingVolumeHierarchy.PointAndIndex
{
Position = aabbs[i].Center,
Index = i
};
}
var bvh = new BoundingVolumeHierarchy(nodes);
bvh.Build(points, aabbs, out numNodes, useSah: true);
points.Dispose();
aabbs.Dispose();
}
// Build mesh sections
BoundingVolumeHierarchy.Node * nodesPtr = (BoundingVolumeHierarchy.Node *)nodes.GetUnsafePtr();
List <MeshBuilder.TempSection> sections = MeshBuilder.BuildSections(nodesPtr, numNodes, primitives);
// Allocate collider
int meshDataSize = Mesh.CalculateMeshDataSize(numNodes, sections);
int totalColliderSize = Math.NextMultipleOf(sizeof(MeshCollider), 16) + meshDataSize;
MeshCollider *meshCollider = (MeshCollider *)UnsafeUtility.Malloc(totalColliderSize, 16, Allocator.Temp);
// Initialize it
{
UnsafeUtility.MemClear(meshCollider, totalColliderSize);
meshCollider->MemorySize = totalColliderSize;
meshCollider->m_Header.Type = ColliderType.Mesh;
meshCollider->m_Header.CollisionType = CollisionType.Composite;
meshCollider->m_Header.Version += 1;
meshCollider->m_Header.Magic = 0xff;
ref var mesh = ref meshCollider->Mesh;
mesh.Init(nodesPtr, numNodes, sections, filter ?? CollisionFilter.Default, material ?? Material.Default);
// Calculate combined filter
meshCollider->m_Header.Filter = mesh.Sections[0].Filters[0];
for (int i = 0; i < mesh.Sections.Length; ++i)
{
foreach (CollisionFilter f in mesh.Sections[i].Filters)
{
meshCollider->m_Header.Filter = CollisionFilter.CreateUnion(meshCollider->m_Header.Filter, f);
}
}
meshCollider->m_Aabb = meshCollider->Mesh.BoundingVolumeHierarchy.Domain;
meshCollider->NumColliderKeyBits = meshCollider->Mesh.NumColliderKeyBits;
}