Files
HauntedBloodlines/Assets/Obi/Scripts/Common/Backends/Burst/Constraints/ParticleCollision/BurstParticleFrictionConstraintsBatch.cs
2025-05-29 22:31:40 +03:00

288 lines
15 KiB
C#

#if (OBI_BURST && OBI_MATHEMATICS && OBI_COLLECTIONS)
using UnityEngine;
using Unity.Jobs;
using Unity.Collections;
using Unity.Collections.LowLevel.Unsafe;
using Unity.Mathematics;
using Unity.Burst;
using System.Collections;
namespace Obi
{
public class BurstParticleFrictionConstraintsBatch : BurstConstraintsBatchImpl, IParticleFrictionConstraintsBatchImpl
{
public BatchData batchData;
public BurstParticleFrictionConstraintsBatch(BurstParticleFrictionConstraints constraints)
{
m_Constraints = constraints;
m_ConstraintType = Oni.ConstraintType.ParticleFriction;
}
public BurstParticleFrictionConstraintsBatch(BatchData batchData) : base()
{
this.batchData = batchData;
}
public override JobHandle Initialize(JobHandle inputDeps, float substepTime)
{
return inputDeps;
}
public override JobHandle Evaluate(JobHandle inputDeps, float stepTime, float substepTime, int substeps)
{
if (!((BurstSolverImpl)constraints.solver).particleContacts.IsCreated)
return inputDeps;
var projectConstraints = new ParticleFrictionConstraintsBatchJob()
{
positions = solverImplementation.positions,
prevPositions = solverImplementation.prevPositions,
orientations = solverImplementation.orientations,
prevOrientations = solverImplementation.prevOrientations,
invMasses = solverImplementation.invMasses,
invInertiaTensors = solverImplementation.invInertiaTensors,
radii = solverImplementation.principalRadii,
particleMaterialIndices = solverImplementation.collisionMaterials,
collisionMaterials = ObiColliderWorld.GetInstance().collisionMaterials.AsNativeArray<BurstCollisionMaterial>(),
simplices = solverImplementation.simplices,
simplexCounts = solverImplementation.simplexCounts,
deltas = solverImplementation.positionDeltas,
counts = solverImplementation.positionConstraintCounts,
orientationDeltas = solverImplementation.orientationDeltas,
orientationCounts = solverImplementation.orientationConstraintCounts,
contacts = ((BurstSolverImpl)constraints.solver).particleContacts,
batchData = batchData,
substepTime = substepTime,
};
int batchCount = batchData.isLast ? batchData.workItemCount : 1;
return projectConstraints.Schedule(batchData.workItemCount, batchCount, inputDeps);
}
public override JobHandle Apply(JobHandle inputDeps, float substepTime)
{
if (!((BurstSolverImpl)constraints.solver).particleContacts.IsCreated)
return inputDeps;
var parameters = solverAbstraction.GetConstraintParameters(m_ConstraintType);
var applyConstraints = new ApplyBatchedCollisionConstraintsBatchJob()
{
contacts = ((BurstSolverImpl)constraints.solver).particleContacts,
simplices = solverImplementation.simplices,
simplexCounts = solverImplementation.simplexCounts,
positions = solverImplementation.positions,
deltas = solverImplementation.positionDeltas,
counts = solverImplementation.positionConstraintCounts,
orientations = solverImplementation.orientations,
orientationDeltas = solverImplementation.orientationDeltas,
orientationCounts = solverImplementation.orientationConstraintCounts,
constraintParameters = parameters,
batchData = batchData
};
int batchCount = batchData.isLast ? batchData.workItemCount : 1;
return applyConstraints.Schedule(batchData.workItemCount, batchCount, inputDeps);
}
[BurstCompile]
public struct ParticleFrictionConstraintsBatchJob : IJobParallelFor
{
[ReadOnly] public NativeArray<float4> positions;
[ReadOnly] public NativeArray<float4> prevPositions;
[ReadOnly] public NativeArray<quaternion> orientations;
[ReadOnly] public NativeArray<quaternion> prevOrientations;
[ReadOnly] public NativeArray<float> invMasses;
[ReadOnly] public NativeArray<float4> invInertiaTensors;
[ReadOnly] public NativeArray<float4> radii;
[ReadOnly] public NativeArray<int> particleMaterialIndices;
[ReadOnly] public NativeArray<BurstCollisionMaterial> collisionMaterials;
// simplex arrays:
[ReadOnly] public NativeArray<int> simplices;
[ReadOnly] public SimplexCounts simplexCounts;
[NativeDisableContainerSafetyRestriction] [NativeDisableParallelForRestriction] public NativeArray<float4> deltas;
[NativeDisableContainerSafetyRestriction] [NativeDisableParallelForRestriction] public NativeArray<int> counts;
[NativeDisableContainerSafetyRestriction] [NativeDisableParallelForRestriction] public NativeArray<quaternion> orientationDeltas;
[NativeDisableContainerSafetyRestriction] [NativeDisableParallelForRestriction] public NativeArray<int> orientationCounts;
[NativeDisableContainerSafetyRestriction] [NativeDisableParallelForRestriction] public NativeArray<BurstContact> contacts;
[ReadOnly] public BatchData batchData;
[ReadOnly] public float substepTime;
public void Execute(int workItemIndex)
{
int start, end;
batchData.GetConstraintRange(workItemIndex, out start, out end);
for (int i = start; i < end; ++i)
{
var contact = contacts[i];
int simplexStartA = simplexCounts.GetSimplexStartAndSize(contact.bodyA, out int simplexSizeA);
int simplexStartB = simplexCounts.GetSimplexStartAndSize(contact.bodyB, out int simplexSizeB);
// Combine collision materials:
BurstCollisionMaterial material = CombineCollisionMaterials(simplices[simplexStartA], simplices[simplexStartB]);
float4 prevPositionA = float4.zero;
float4 linearVelocityA = float4.zero;
float4 angularVelocityA = float4.zero;
float4 invInertiaTensorA = float4.zero;
quaternion orientationA = new quaternion(0, 0, 0, 0);
float simplexRadiusA = 0;
float4 prevPositionB = float4.zero;
float4 linearVelocityB = float4.zero;
float4 angularVelocityB = float4.zero;
float4 invInertiaTensorB = float4.zero;
quaternion orientationB = new quaternion(0, 0, 0, 0);
float simplexRadiusB = 0;
for (int j = 0; j < simplexSizeA; ++j)
{
int particleIndex = simplices[simplexStartA + j];
prevPositionA += prevPositions[particleIndex] * contact.pointA[j];
linearVelocityA += BurstIntegration.DifferentiateLinear(positions[particleIndex], prevPositions[particleIndex], substepTime) * contact.pointA[j];
angularVelocityA += BurstIntegration.DifferentiateAngular(orientations[particleIndex], prevOrientations[particleIndex], substepTime) * contact.pointA[j];
invInertiaTensorA += invInertiaTensors[particleIndex] * contact.pointA[j];
orientationA.value += orientations[particleIndex].value * contact.pointA[j];
simplexRadiusA += BurstMath.EllipsoidRadius(contact.normal, prevOrientations[particleIndex], radii[particleIndex].xyz) * contact.pointA[j];
}
for (int j = 0; j < simplexSizeB; ++j)
{
int particleIndex = simplices[simplexStartB + j];
prevPositionB += prevPositions[particleIndex] * contact.pointB[j];
linearVelocityB += BurstIntegration.DifferentiateLinear(positions[particleIndex], prevPositions[particleIndex], substepTime) * contact.pointB[j];
angularVelocityB += BurstIntegration.DifferentiateAngular(orientations[particleIndex], prevOrientations[particleIndex], substepTime) * contact.pointB[j];
invInertiaTensorB += invInertiaTensors[particleIndex] * contact.pointB[j];
orientationB.value += orientations[particleIndex].value * contact.pointB[j];
simplexRadiusB += BurstMath.EllipsoidRadius(contact.normal, prevOrientations[particleIndex], radii[particleIndex].xyz) * contact.pointB[j];
}
float4 rA = float4.zero, rB = float4.zero;
// Consider angular velocities if rolling contacts are enabled:
if (material.rollingContacts > 0)
{
rA = -contact.normal * simplexRadiusA;
rB = contact.normal * simplexRadiusB;
linearVelocityA += new float4(math.cross(angularVelocityA.xyz, rA.xyz), 0);
linearVelocityB += new float4(math.cross(angularVelocityB.xyz, rB.xyz), 0);
}
// Calculate relative velocity:
float4 relativeVelocity = linearVelocityA - linearVelocityB;
// Calculate friction impulses (in the tangent and bitangent ddirections):
float2 impulses = contact.SolveFriction(relativeVelocity, material.staticFriction, material.dynamicFriction, substepTime);
// Apply friction impulses to both particles:
if (math.abs(impulses.x) > BurstMath.epsilon || math.abs(impulses.y) > BurstMath.epsilon)
{
float4 tangentImpulse = impulses.x * contact.tangent;
float4 bitangentImpulse = impulses.y * contact.bitangent;
float4 totalImpulse = tangentImpulse + bitangentImpulse;
float baryScale = BurstMath.BaryScale(contact.pointA);
for (int j = 0; j < simplexSizeA; ++j)
{
int particleIndex = simplices[simplexStartA + j];
deltas[particleIndex] += (tangentImpulse * contact.tangentInvMassA + bitangentImpulse * contact.bitangentInvMassA) * substepTime * contact.pointA[j] * baryScale;
counts[particleIndex]++;
}
baryScale = BurstMath.BaryScale(contact.pointB);
for (int j = 0; j < simplexSizeB; ++j)
{
int particleIndex = simplices[simplexStartB + j];
deltas[particleIndex] -= (tangentImpulse * contact.tangentInvMassB + bitangentImpulse * contact.bitangentInvMassB) * substepTime * contact.pointB[j] * baryScale;
counts[particleIndex]++;
}
// Rolling contacts:
if (material.rollingContacts > 0)
{
// Calculate angular velocity deltas due to friction impulse:
float4x4 solverInertiaA = BurstMath.TransformInertiaTensor(invInertiaTensorA, orientationA);
float4x4 solverInertiaB = BurstMath.TransformInertiaTensor(invInertiaTensorB, orientationB);
float4 angVelDeltaA = math.mul(solverInertiaA, new float4(math.cross(rA.xyz, totalImpulse.xyz), 0));
float4 angVelDeltaB = -math.mul(solverInertiaB, new float4(math.cross(rB.xyz, totalImpulse.xyz), 0));
// Final angular velocities, after adding the deltas:
angularVelocityA += angVelDeltaA;
angularVelocityB += angVelDeltaB;
// Calculate weights (inverse masses):
float invMassA = math.length(math.mul(solverInertiaA, math.normalizesafe(angularVelocityA)));
float invMassB = math.length(math.mul(solverInertiaB, math.normalizesafe(angularVelocityB)));
// Calculate rolling axis and angular velocity deltas:
float4 rollAxis = float4.zero;
float rollingImpulse = contact.SolveRollingFriction(angularVelocityA, angularVelocityB, material.rollingFriction, invMassA, invMassB, ref rollAxis);
angVelDeltaA += rollAxis * rollingImpulse * invMassA;
angVelDeltaB -= rollAxis * rollingImpulse * invMassB;
// Apply orientation deltas to particles:
quaternion orientationDeltaA = BurstIntegration.AngularVelocityToSpinQuaternion(orientationA, angVelDeltaA, substepTime);
quaternion orientationDeltaB = BurstIntegration.AngularVelocityToSpinQuaternion(orientationB, angVelDeltaB, substepTime);
for (int j = 0; j < simplexSizeA; ++j)
{
int particleIndex = simplices[simplexStartA + j];
quaternion qA = orientationDeltas[particleIndex];
qA.value += orientationDeltaA.value;
orientationDeltas[particleIndex] = qA;
orientationCounts[particleIndex]++;
}
for (int j = 0; j < simplexSizeB; ++j)
{
int particleIndex = simplices[simplexStartB+ j];
quaternion qB = orientationDeltas[particleIndex];
qB.value += orientationDeltaB.value;
orientationDeltas[particleIndex] = qB;
orientationCounts[particleIndex]++;
}
}
}
contacts[i] = contact;
}
}
private BurstCollisionMaterial CombineCollisionMaterials(int entityA, int entityB)
{
// Combine collision materials:
int aMaterialIndex = particleMaterialIndices[entityA];
int bMaterialIndex = particleMaterialIndices[entityB];
if (aMaterialIndex >= 0 && bMaterialIndex >= 0)
return BurstCollisionMaterial.CombineWith(collisionMaterials[aMaterialIndex], collisionMaterials[bMaterialIndex]);
else if (aMaterialIndex >= 0)
return collisionMaterials[aMaterialIndex];
else if (bMaterialIndex >= 0)
return collisionMaterials[bMaterialIndex];
return new BurstCollisionMaterial();
}
}
}
}
#endif