/**
* This function generates tethers for a given set of particles, all belonging a connected graph.
* This is use ful when the cloth mesh is composed of several
* disjoint islands, and we dont want tethers in one island to anchor particles to fixed particles in a different island.
*
* Inside each island, fixed particles are partitioned again into "islands", then generates up to maxTethers constraints for each
* particle linking it to the closest point in each fixed island.
*/
private void GenerateTethersForIsland(HashSet <int> particles, int maxTethers)
{
if (maxTethers > 0)
{
ObiTetherConstraintBatch tetherBatch = new ObiTetherConstraintBatch(true, false);
TetherConstraints.AddBatch(tetherBatch);
List <HashSet <int> > fixedIslands = GenerateIslands(particles, true);
// Generate tether constraints:
foreach (int i in particles)
{
if (invMasses[i] == 0 || !active[i])
{
continue;
}
List <KeyValuePair <float, int> > tethers = new List <KeyValuePair <float, int> >(fixedIslands.Count * maxTethers);
// Find the closest particle in each island, and add it to tethers.
foreach (HashSet <int> island in fixedIslands)
{
int closest = -1;
float minDistance = Mathf.Infinity;
foreach (int j in island)
{
float distance = (topology.heVertices[i].position - topology.heVertices[j].position).sqrMagnitude;
if (distance < minDistance)
{
minDistance = distance;
closest = j;
}
}
if (closest >= 0)
{
tethers.Add(new KeyValuePair <float, int>(minDistance, closest));
}
}
// Sort tether indices by distance:
tethers.Sort(
delegate(KeyValuePair <float, int> x, KeyValuePair <float, int> y)
{
return(x.Key.CompareTo(y.Key));
}
);
// Create constraints for "maxTethers" closest anchor particles:
for (int k = 0; k < Mathf.Min(maxTethers, tethers.Count); ++k)
{
tetherBatch.AddConstraint(i, tethers[k].Value, Mathf.Sqrt(tethers[k].Key),
TetherConstraints.tetherScale,
TetherConstraints.stiffness);
}
}
tetherBatch.Cook();
}
}
/**
* Automatically generates tether constraints for the cloth.
* Partitions fixed particles into "islands", then generates up to maxTethers constraints for each
* particle, linking it to the closest point in each island.
*/
public override bool GenerateTethers()
{
if (!Initialized)
{
return(false);
}
TetherConstraints.Clear();
GenerateFixedTethers(2);
return(true);
}
/**
* Automatically generates tether constraints for the cloth.
* Partitions fixed particles into "islands", then generates up to maxTethers constraints for each
* particle, linking it to the closest point in each island.
*/
public override bool GenerateTethers()
{
if (!Initialized)
{
return(false);
}
TetherConstraints.Clear();
// generate disjoint islands:
List <HashSet <int> > islands = GenerateIslands(System.Linq.Enumerable.Range(0, topology.heVertices.Length), false);
// generate tethers for each one:
foreach (HashSet <int> island in islands)
{
GenerateTethersForIsland(island, 4);
}
return(true);
}
/**
* Automatically generates tether constraints for the cloth.
* Partitions fixed particles into "islands", then generates up to maxTethers constraints for each
* particle, linking it to the closest point in each island.
*/
public override bool GenerateTethers(TetherType type)
{
if (!Initialized)
{
return(false);
}
TetherConstraints.Clear();
if (type == TetherType.Hierarchical)
{
GenerateHierarchicalTethers(5);
}
else
{
GenerateFixedTethers(2);
}
return(true);
}
private void GenerateHierarchicalTethers(int maxLevels)
{
ObiTetherConstraintBatch tetherBatch = new ObiTetherConstraintBatch(true, false, MIN_YOUNG_MODULUS, MAX_YOUNG_MODULUS);
TetherConstraints.AddBatch(tetherBatch);
// for each level:
for (int i = 1; i <= maxLevels; ++i)
{
int stride = i * 2;
// for each particle:
for (int j = 0; j < usedParticles - stride; ++j)
{
int nextParticle = j + stride;
tetherBatch.AddConstraint(j, nextParticle % usedParticles, interParticleDistance * stride, 1, 1);
}
}
tetherBatch.Cook();
}
private void GenerateFixedTethers(int maxTethers)
{
ObiTetherConstraintBatch tetherBatch = new ObiTetherConstraintBatch(true, false, MIN_YOUNG_MODULUS, MAX_YOUNG_MODULUS);
TetherConstraints.AddBatch(tetherBatch);
List <HashSet <int> > islands = new List <HashSet <int> >();
// Partition fixed particles into islands:
for (int i = 0; i < usedParticles; i++)
{
if (invMasses[i] > 0 || !active[i])
{
continue;
}
int assignedIsland = -1;
// keep a list of islands to merge with ours:
List <int> mergeableIslands = new List <int>();
// See if any of our neighbors is part of an island:
int prev = Mathf.Max(i - 1, 0);
int next = Mathf.Min(i + 1, usedParticles - 1);
for (int k = 0; k < islands.Count; ++k)
{
if ((active[prev] && islands[k].Contains(prev)) ||
(active[next] && islands[k].Contains(next)))
{
// if we are not in an island yet, pick this one:
if (assignedIsland < 0)
{
assignedIsland = k;
islands[k].Add(i);
}
// if we already are in an island, we will merge this newfound island with ours:
else if (assignedIsland != k && !mergeableIslands.Contains(k))
{
mergeableIslands.Add(k);
}
}
}
// merge islands with the assigned one:
foreach (int merge in mergeableIslands)
{
islands[assignedIsland].UnionWith(islands[merge]);
}
// remove merged islands:
mergeableIslands.Sort();
mergeableIslands.Reverse();
foreach (int merge in mergeableIslands)
{
islands.RemoveAt(merge);
}
// If no adjacent particle is in an island, create a new one:
if (assignedIsland < 0)
{
islands.Add(new HashSet <int>()
{
i
});
}
}
// Generate tether constraints:
for (int i = 0; i < usedParticles; ++i)
{
if (invMasses[i] == 0)
{
continue;
}
List <KeyValuePair <float, int> > tethers = new List <KeyValuePair <float, int> >(islands.Count);
// Find the closest particle in each island, and add it to tethers.
foreach (HashSet <int> island in islands)
{
int closest = -1;
float minDistance = Mathf.Infinity;
foreach (int j in island)
{
// TODO: Use linear distance along the rope in a more efficient way. precalculate it on generation!
int min = Mathf.Min(i, j);
int max = Mathf.Max(i, j);
float distance = 0;
for (int k = min; k < max; ++k)
{
distance += Vector3.Distance(positions[k],
positions[k + 1]);
}
if (distance < minDistance)
{
minDistance = distance;
closest = j;
}
}
if (closest >= 0)
{
tethers.Add(new KeyValuePair <float, int>(minDistance, closest));
}
}
// Sort tether indices by distance:
tethers.Sort(
delegate(KeyValuePair <float, int> x, KeyValuePair <float, int> y)
{
return(x.Key.CompareTo(y.Key));
}
);
// Create constraints for "maxTethers" closest anchor particles:
for (int k = 0; k < Mathf.Min(maxTethers, tethers.Count); ++k)
{
tetherBatch.AddConstraint(i, tethers[k].Value, tethers[k].Key, 1, 1);
}
}
tetherBatch.Cook();
}
/**
* Generates the particle based physical representation of the rope. This is the initialization method for the rope object
* and should not be called directly once the object has been created.
*/
protected override IEnumerator Initialize()
{
initialized = false;
initializing = true;
interParticleDistance = -1;
RemoveFromSolver(null);
if (ropePath == null)
{
Debug.LogError("Cannot initialize rope. There's no ropePath present. Please provide a spline to define the shape of the rope");
yield break;
}
ropePath.RecalculateSplineLenght(0.00001f, 7);
closed = ropePath.closed;
restLength = ropePath.Length;
usedParticles = Mathf.CeilToInt(restLength / thickness * resolution) + (closed ? 0:1);
totalParticles = usedParticles + pooledParticles; //allocate extra particles to allow for lenght change and tearing.
active = new bool[totalParticles];
positions = new Vector3[totalParticles];
velocities = new Vector3[totalParticles];
invMasses = new float[totalParticles];
principalRadii = new Vector3[totalParticles];
phases = new int[totalParticles];
restPositions = new Vector4[totalParticles];
tearResistance = new float[totalParticles];
colors = new Color[totalParticles];
int numSegments = usedParticles - (closed ? 0:1);
if (numSegments > 0)
{
interParticleDistance = restLength / (float)numSegments;
}
else
{
interParticleDistance = 0;
}
float radius = interParticleDistance * resolution;
for (int i = 0; i < usedParticles; i++)
{
active[i] = true;
invMasses[i] = 1.0f / DEFAULT_PARTICLE_MASS;
float mu = ropePath.GetMuAtLenght(interParticleDistance * i);
positions[i] = transform.InverseTransformPoint(ropePath.transform.TransformPoint(ropePath.GetPositionAt(mu)));
principalRadii[i] = Vector3.one * radius;
phases[i] = Oni.MakePhase(1, selfCollisions?Oni.ParticlePhase.SelfCollide:0);
tearResistance[i] = 1;
colors[i] = Color.white;
if (i % 100 == 0)
{
yield return(new CoroutineJob.ProgressInfo("ObiRope: generating particles...", i / (float)usedParticles));
}
}
// Initialize basic data for pooled particles:
for (int i = usedParticles; i < totalParticles; i++)
{
active[i] = false;
invMasses[i] = 1.0f / DEFAULT_PARTICLE_MASS;
principalRadii[i] = Vector3.one * radius;
phases[i] = Oni.MakePhase(1, selfCollisions?Oni.ParticlePhase.SelfCollide:0);
tearResistance[i] = 1;
colors[i] = Color.white;
if (i % 100 == 0)
{
yield return(new CoroutineJob.ProgressInfo("ObiRope: generating particles...", i / (float)usedParticles));
}
}
DistanceConstraints.Clear();
ObiDistanceConstraintBatch distanceBatch = new ObiDistanceConstraintBatch(false, false, MIN_YOUNG_MODULUS, MAX_YOUNG_MODULUS);
DistanceConstraints.AddBatch(distanceBatch);
for (int i = 0; i < numSegments; i++)
{
distanceBatch.AddConstraint(i, (i + 1) % (ropePath.closed ? usedParticles:usedParticles + 1), interParticleDistance, 1, 1);
if (i % 500 == 0)
{
yield return(new CoroutineJob.ProgressInfo("ObiRope: generating structural constraints...", i / (float)numSegments));
}
}
BendingConstraints.Clear();
ObiBendConstraintBatch bendingBatch = new ObiBendConstraintBatch(false, false, MIN_YOUNG_MODULUS, MAX_YOUNG_MODULUS);
BendingConstraints.AddBatch(bendingBatch);
for (int i = 0; i < usedParticles - (closed?0:2); i++)
{
// rope bending constraints always try to keep it completely straight:
bendingBatch.AddConstraint(i, (i + 2) % usedParticles, (i + 1) % usedParticles, 0, 0, 1);
if (i % 500 == 0)
{
yield return(new CoroutineJob.ProgressInfo("ObiRope: adding bend constraints...", i / (float)usedParticles));
}
}
// Initialize tether constraints:
TetherConstraints.Clear();
// Initialize pin constraints:
PinConstraints.Clear();
ObiPinConstraintBatch pinBatch = new ObiPinConstraintBatch(false, false, 0, MAX_YOUNG_MODULUS);
PinConstraints.AddBatch(pinBatch);
initializing = false;
initialized = true;
RegenerateRestPositions();
}
/**
* Generates the particle based physical representation of the rope. This is the initialization method for the rope object
* and should not be called directly once the object has been created.
*/
protected override IEnumerator Initialize()
{
initialized = false;
initializing = true;
interParticleDistance = -1;
RemoveFromSolver(null);
if (ropePath == null)
{
Debug.LogError("Cannot initialize rope. There's no ropePath present. Please provide a spline to define the shape of the rope");
yield break;
}
ropePath.RecalculateSplineLenght(0.00001f, 7);
closed = ropePath.closed;
restLength = ropePath.Length;
usedParticles = Mathf.CeilToInt(restLength / thickness * resolution) + (closed ? 0:1);
totalParticles = usedParticles;
active = new bool[totalParticles];
positions = new Vector3[totalParticles];
orientations = new Quaternion[totalParticles];
velocities = new Vector3[totalParticles];
angularVelocities = new Vector3[totalParticles];
invMasses = new float[totalParticles];
invRotationalMasses = new float[totalParticles];
principalRadii = new Vector3[totalParticles];
phases = new int[totalParticles];
restPositions = new Vector4[totalParticles];
restOrientations = new Quaternion[totalParticles];
colors = new Color[totalParticles];
int numSegments = usedParticles - (closed ? 0:1);
if (numSegments > 0)
{
interParticleDistance = restLength / (float)numSegments;
}
else
{
interParticleDistance = 0;
}
float radius = interParticleDistance * resolution;
for (int i = 0; i < usedParticles; i++)
{
active[i] = true;
invMasses[i] = 1.0f / DEFAULT_PARTICLE_MASS;
invRotationalMasses[i] = 1.0f / DEFAULT_PARTICLE_ROTATIONAL_MASS;
float mu = ropePath.GetMuAtLenght(interParticleDistance * i);
positions[i] = transform.InverseTransformPoint(ropePath.transform.TransformPoint(ropePath.GetPositionAt(mu)));
principalRadii[i] = Vector3.one * radius;
phases[i] = Oni.MakePhase(1, selfCollisions?Oni.ParticlePhase.SelfCollide:0);
colors[i] = Color.white;
if (i % 100 == 0)
{
yield return(new CoroutineJob.ProgressInfo("ObiRod: generating particles...", i / (float)usedParticles));
}
}
StretchShearConstraints.Clear();
ObiStretchShearConstraintBatch stretchBatch = new ObiStretchShearConstraintBatch(false, false, MIN_YOUNG_MODULUS, MAX_YOUNG_MODULUS);
StretchShearConstraints.AddBatch(stretchBatch);
// rotation minimizing frame:
ObiCurveFrame frame = new ObiCurveFrame();
frame.Reset();
for (int i = 0; i < numSegments; i++)
{
int next = (i + 1) % (ropePath.closed ? usedParticles:usedParticles + 1);
float mu = ropePath.GetMuAtLenght(interParticleDistance * i);
Vector3 normal = transform.InverseTransformVector(ropePath.transform.TransformVector(ropePath.GetNormalAt(mu)));
frame.Transport(positions[i], (positions[next] - positions[i]).normalized, 0);
orientations[i] = Quaternion.LookRotation(frame.tangent, normal);
restOrientations[i] = orientations[i];
// Also set the orientation of the next particle. If it is not the last one, we will overwrite it.
// This makes sure that open rods provide an orientation for their last particle (or rather, a phantom segment past the last particle).
orientations[next] = orientations[i];
restOrientations[next] = orientations[i];
stretchBatch.AddConstraint(i, next, interParticleDistance, Quaternion.identity, Vector3.one);
if (i % 500 == 0)
{
yield return(new CoroutineJob.ProgressInfo("ObiRod: generating structural constraints...", i / (float)numSegments));
}
}
BendTwistConstraints.Clear();
ObiBendTwistConstraintBatch twistBatch = new ObiBendTwistConstraintBatch(false, false, MIN_YOUNG_MODULUS, MAX_YOUNG_MODULUS);
BendTwistConstraints.AddBatch(twistBatch);
// the last bend constraint couples the last segment and a phantom segment past the last particle.
for (int i = 0; i < numSegments; i++)
{
int next = (i + 1) % (ropePath.closed ? usedParticles:usedParticles + 1);
Quaternion darboux = keepInitialShape ? ObiUtils.RestDarboux(orientations[i], orientations[next]) : Quaternion.identity;
twistBatch.AddConstraint(i, next, darboux, Vector3.one);
if (i % 500 == 0)
{
yield return(new CoroutineJob.ProgressInfo("ObiRod: generating structural constraints...", i / (float)numSegments));
}
}
ChainConstraints.Clear();
ObiChainConstraintBatch chainBatch = new ObiChainConstraintBatch(false, false, MIN_YOUNG_MODULUS, MAX_YOUNG_MODULUS);
ChainConstraints.AddBatch(chainBatch);
int[] indices = new int[usedParticles + (closed ? 1:0)];
for (int i = 0; i < usedParticles; ++i)
{
indices[i] = i;
}
// Add the first particle as the last index of the chain, if closed.
if (closed)
{
indices[usedParticles] = 0;
}
chainBatch.AddConstraint(indices, interParticleDistance, 1, 1);
// Initialize tether constraints:
TetherConstraints.Clear();
// Initialize pin constraints:
PinConstraints.Clear();
ObiPinConstraintBatch pinBatch = new ObiPinConstraintBatch(false, false, MIN_YOUNG_MODULUS, MAX_YOUNG_MODULUS);
PinConstraints.AddBatch(pinBatch);
initializing = false;
initialized = true;
RegenerateRestPositions();
}
/**
* Generates the particle based physical representation of the cloth mesh. This is the initialization method for the cloth object
* and should not be called directly once the object has been created.
*/
protected override IEnumerator Initialize()
{
initialized = false;
initializing = false;
if (sharedTopology == null)
{
Debug.LogError("No ObiMeshTopology provided. Cannot initialize physical representation.");
yield break;
}
else if (!sharedTopology.Initialized)
{
Debug.LogError("The provided ObiMeshTopology contains no data. Cannot initialize physical representation.");
yield break;
}
initializing = true;
RemoveFromSolver(null);
GameObject.DestroyImmediate(topology);
topology = GameObject.Instantiate(sharedTopology);
active = new bool[topology.heVertices.Length];
positions = new Vector3[topology.heVertices.Length];
restPositions = new Vector4[topology.heVertices.Length];
velocities = new Vector3[topology.heVertices.Length];
invMasses = new float[topology.heVertices.Length];
principalRadii = new Vector3[topology.heVertices.Length];
phases = new int[topology.heVertices.Length];
areaContribution = new float[topology.heVertices.Length];
deformableTriangles = new int[topology.heFaces.Length * 3];
initialScaleMatrix.SetTRS(Vector3.zero, Quaternion.identity, transform.lossyScale);
// Create a particle for each vertex:
for (int i = 0; i < topology.heVertices.Length; i++)
{
Oni.Vertex vertex = topology.heVertices[i];
// Get the particle's area contribution.
areaContribution[i] = 0;
foreach (Oni.Face face in topology.GetNeighbourFacesEnumerator(vertex))
{
areaContribution[i] += topology.GetFaceArea(face) / 3;
}
// Get the shortest neighbour edge, particle radius will be half of its length.
float minEdgeLength = Single.MaxValue;
foreach (Oni.HalfEdge edge in topology.GetNeighbourEdgesEnumerator(vertex))
{
// vertices at each end of the edge:
Vector3 v1 = initialScaleMatrix * topology.heVertices[topology.GetHalfEdgeStartVertex(edge)].position;
Vector3 v2 = initialScaleMatrix * topology.heVertices[edge.endVertex].position;
minEdgeLength = Mathf.Min(minEdgeLength, Vector3.Distance(v1, v2));
}
active[i] = true;
invMasses[i] = (skinnedMeshRenderer == null && areaContribution[i] > 0) ? (1.0f / (DEFAULT_PARTICLE_MASS * areaContribution[i])) : 0;
positions[i] = initialScaleMatrix * vertex.position;
restPositions[i] = positions[i];
restPositions[i][3] = 1; // activate rest position.
principalRadii[i] = Vector3.one * minEdgeLength * 0.5f;
phases[i] = Oni.MakePhase(1, selfCollisions?Oni.ParticlePhase.SelfCollide:0);
if (i % 500 == 0)
{
yield return(new CoroutineJob.ProgressInfo("ObiCloth: generating particles...", i / (float)topology.heVertices.Length));
}
}
// Generate deformable triangles:
for (int i = 0; i < topology.heFaces.Length; i++)
{
Oni.Face face = topology.heFaces[i];
Oni.HalfEdge e1 = topology.heHalfEdges[face.halfEdge];
Oni.HalfEdge e2 = topology.heHalfEdges[e1.nextHalfEdge];
Oni.HalfEdge e3 = topology.heHalfEdges[e2.nextHalfEdge];
deformableTriangles[i * 3] = e1.endVertex;
deformableTriangles[i * 3 + 1] = e2.endVertex;
deformableTriangles[i * 3 + 2] = e3.endVertex;
if (i % 500 == 0)
{
yield return(new CoroutineJob.ProgressInfo("ObiCloth: generating deformable geometry...", i / (float)topology.heFaces.Length));
}
}
List <ObiMeshTopology.HEEdge> edges = topology.GetEdgeList();
DistanceConstraints.Clear();
ObiDistanceConstraintBatch distanceBatch = new ObiDistanceConstraintBatch(true, false);
DistanceConstraints.AddBatch(distanceBatch);
// Create distance springs:
for (int i = 0; i < edges.Count; i++)
{
Oni.HalfEdge hedge = topology.heHalfEdges[edges[i].halfEdgeIndex];
Oni.Vertex startVertex = topology.heVertices[topology.GetHalfEdgeStartVertex(hedge)];
Oni.Vertex endVertex = topology.heVertices[hedge.endVertex];
distanceBatch.AddConstraint(topology.GetHalfEdgeStartVertex(hedge), hedge.endVertex, Vector3.Distance(initialScaleMatrix * startVertex.position, initialScaleMatrix * endVertex.position), 1, 1);
if (i % 500 == 0)
{
yield return(new CoroutineJob.ProgressInfo("ObiCloth: generating structural constraints...", i / (float)topology.heHalfEdges.Length));
}
}
// Cook distance constraints, for better cache and SIMD use:
distanceBatch.Cook();
// Create aerodynamic constraints:
AerodynamicConstraints.Clear();
ObiAerodynamicConstraintBatch aeroBatch = new ObiAerodynamicConstraintBatch(false, false);
AerodynamicConstraints.AddBatch(aeroBatch);
for (int i = 0; i < topology.heVertices.Length; i++)
{
aeroBatch.AddConstraint(i,
areaContribution[i],
AerodynamicConstraints.dragCoefficient,
AerodynamicConstraints.liftCoefficient);
if (i % 500 == 0)
{
yield return(new CoroutineJob.ProgressInfo("ObiCloth: generating aerodynamic constraints...", i / (float)topology.heFaces.Length));
}
}
//Create skin constraints (if needed)
if (skinnedMeshRenderer != null)
{
SkinConstraints.Clear();
ObiSkinConstraintBatch skinBatch = new ObiSkinConstraintBatch(true, false);
SkinConstraints.AddBatch(skinBatch);
for (int i = 0; i < topology.heVertices.Length; ++i)
{
skinBatch.AddConstraint(i, initialScaleMatrix * topology.heVertices[i].position, Vector3.up, 0.05f, 0.1f, 0, 1);
if (i % 500 == 0)
{
yield return(new CoroutineJob.ProgressInfo("ObiCloth: generating skin constraints...", i / (float)topology.heVertices.Length));
}
}
for (int i = 0; i < topology.normals.Length; ++i)
{
skinBatch.skinNormals[topology.visualMap[i]] = topology.normals[i];
}
skinBatch.Cook();
}
//Create pressure constraints if the mesh is closed:
VolumeConstraints.Clear();
if (topology.IsClosed)
{
ObiVolumeConstraintBatch volumeBatch = new ObiVolumeConstraintBatch(false, false);
VolumeConstraints.AddBatch(volumeBatch);
float avgInitialScale = (initialScaleMatrix.m00 + initialScaleMatrix.m11 + initialScaleMatrix.m22) * 0.33f;
int[] triangleIndices = new int[topology.heFaces.Length * 3];
for (int i = 0; i < topology.heFaces.Length; i++)
{
Oni.Face face = topology.heFaces[i];
Oni.HalfEdge e1 = topology.heHalfEdges[face.halfEdge];
Oni.HalfEdge e2 = topology.heHalfEdges[e1.nextHalfEdge];
Oni.HalfEdge e3 = topology.heHalfEdges[e2.nextHalfEdge];
triangleIndices[i * 3] = e1.endVertex;
triangleIndices[i * 3 + 1] = e2.endVertex;
triangleIndices[i * 3 + 2] = e3.endVertex;
if (i % 500 == 0)
{
yield return(new CoroutineJob.ProgressInfo("ObiCloth: generating volume constraints...", i / (float)topology.heFaces.Length));
}
}
volumeBatch.AddConstraint(triangleIndices, topology.MeshVolume * avgInitialScale, 1, 1);
}
//Create bending constraints:
BendingConstraints.Clear();
ObiBendConstraintBatch bendBatch = new ObiBendConstraintBatch(true, false);
BendingConstraints.AddBatch(bendBatch);
Dictionary <int, int> cons = new Dictionary <int, int>();
for (int i = 0; i < topology.heVertices.Length; i++)
{
Oni.Vertex vertex = topology.heVertices[i];
foreach (Oni.Vertex n1 in topology.GetNeighbourVerticesEnumerator(vertex))
{
float cosBest = 0;
Oni.Vertex vBest = n1;
foreach (Oni.Vertex n2 in topology.GetNeighbourVerticesEnumerator(vertex))
{
float cos = Vector3.Dot((n1.position - vertex.position).normalized,
(n2.position - vertex.position).normalized);
if (cos < cosBest)
{
cosBest = cos;
vBest = n2;
}
}
if (!cons.ContainsKey(vBest.index) || cons[vBest.index] != n1.index)
{
cons[n1.index] = vBest.index;
Vector3 n1Pos = initialScaleMatrix * n1.position;
Vector3 bestPos = initialScaleMatrix * vBest.position;
Vector3 vertexPos = initialScaleMatrix * vertex.position;
float[] bendRestPositions = new float[] { n1Pos[0], n1Pos[1], n1Pos[2],
bestPos[0], bestPos[1], bestPos[2],
vertexPos[0], vertexPos[1], vertexPos[2] };
float restBend = Oni.BendingConstraintRest(bendRestPositions);
bendBatch.AddConstraint(n1.index, vBest.index, vertex.index, restBend, 0, 1);
}
}
if (i % 500 == 0)
{
yield return(new CoroutineJob.ProgressInfo("ObiCloth: adding bend constraints...", i / (float)sharedTopology.heVertices.Length));
}
}
bendBatch.Cook();
// Initialize tether constraints:
TetherConstraints.Clear();
// Initialize pin constraints:
PinConstraints.Clear();
ObiPinConstraintBatch pinBatch = new ObiPinConstraintBatch(false, false);
PinConstraints.AddBatch(pinBatch);
initializing = false;
initialized = true;
if (skinnedMeshRenderer == null)
{
InitializeWithRegularMesh();
}
else
{
InitializeWithSkinnedMesh();
}
}
/**
* Automatically generates tether constraints for the cloth.
* Partitions fixed particles into "islands", then generates up to maxTethers constraints for each
* particle, linking it to the closest point in each island.
*/
public override bool GenerateTethers(int maxTethers)
{
if (!Initialized)
{
return(false);
}
TetherConstraints.Clear();
if (maxTethers > 0)
{
ObiTetherConstraintBatch tetherBatch = new ObiTetherConstraintBatch(true, false);
TetherConstraints.AddBatch(tetherBatch);
List <HashSet <int> > islands = new List <HashSet <int> >();
// Partition fixed particles into islands:
for (int i = 0; i < topology.heVertices.Length; i++)
{
Oni.Vertex vertex = topology.heVertices[i];
if (invMasses[i] > 0 || !active[i])
{
continue;
}
int assignedIsland = -1;
// keep a list of islands to merge with ours:
List <int> mergeableIslands = new List <int>();
// See if any of our neighbors is part of an island:
foreach (Oni.Vertex n in topology.GetNeighbourVerticesEnumerator(vertex))
{
if (!active[n.index])
{
continue;
}
for (int k = 0; k < islands.Count; ++k)
{
if (islands[k].Contains(n.index))
{
// if we are not in an island yet, pick this one:
if (assignedIsland < 0)
{
assignedIsland = k;
islands[k].Add(i);
}
// if we already are in an island, we will merge this newfound island with ours:
else if (assignedIsland != k && !mergeableIslands.Contains(k))
{
mergeableIslands.Add(k);
}
}
}
}
// merge islands with the assigned one:
foreach (int merge in mergeableIslands)
{
islands[assignedIsland].UnionWith(islands[merge]);
}
// remove merged islands:
mergeableIslands.Sort();
mergeableIslands.Reverse();
foreach (int merge in mergeableIslands)
{
islands.RemoveAt(merge);
}
// If no adjacent particle is in an island, create a new one:
if (assignedIsland < 0)
{
islands.Add(new HashSet <int>()
{
i
});
}
}
// Generate tether constraints:
for (int i = 0; i < invMasses.Length; ++i)
{
if (invMasses[i] == 0 || !active[i])
{
continue;
}
List <KeyValuePair <float, int> > tethers = new List <KeyValuePair <float, int> >(islands.Count * maxTethers);
// Find the closest particle in each island, and add it to tethers.
foreach (HashSet <int> island in islands)
{
int closest = -1;
float minDistance = Mathf.Infinity;
foreach (int j in island)
{
float distance = (topology.heVertices[i].position - topology.heVertices[j].position).sqrMagnitude;
if (distance < minDistance)
{
minDistance = distance;
closest = j;
}
}
if (closest >= 0)
{
tethers.Add(new KeyValuePair <float, int>(minDistance, closest));
}
}
// Sort tether indices by distance:
tethers.Sort(
delegate(KeyValuePair <float, int> x, KeyValuePair <float, int> y)
{
return(x.Key.CompareTo(y.Key));
}
);
// Create constraints for "maxTethers" closest anchor particles:
for (int k = 0; k < Mathf.Min(maxTethers, tethers.Count); ++k)
{
tetherBatch.AddConstraint(i, tethers[k].Value, Mathf.Sqrt(tethers[k].Key),
TetherConstraints.tetherScale,
TetherConstraints.stiffness);
}
}
tetherBatch.Cook();
}
return(true);
}
