UniVRM/Assets/VRM10_Samples/ClothSample/ClothWarp/Runtime/Jobs/Collision.cs

319 lines
11 KiB
C#

using System;
using System.Collections.Generic;
using SphereTriangle;
using UniGLTF.SpringBoneJobs.Blittables;
using Unity.Collections;
using Unity.Jobs;
using UnityEngine;
using UnityEngine.Jobs;
namespace UniVRM10.ClothWarp.Jobs
{
public struct InputColliderJob : IJobParallelForTransform
{
[WriteOnly] public NativeArray<Matrix4x4> CurrentCollider;
public void Execute(int colliderIndex, TransformAccess transform)
{
CurrentCollider[colliderIndex] = transform.localToWorldMatrix;
}
}
public struct StrandCollisionJob : IJobParallelFor
{
// collider
[ReadOnly] public NativeArray<BlittableCollider> Colliders;
[ReadOnly] public NativeArray<Matrix4x4> CurrentColliders;
// particle
[ReadOnly] public NativeArray<TransformInfo> Info;
[ReadOnly] public NativeArray<Vector3> NextPositions;
[ReadOnly] public NativeArray<bool> ClothUsedParticles;
[WriteOnly] public NativeArray<Vector3> StrandCollision;
public void Execute(int particleIndex)
{
if (!ClothUsedParticles[particleIndex])
{
var info = Info[particleIndex];
var pos = NextPositions[particleIndex];
for (int colliderIndex = 0; colliderIndex < Colliders.Length; ++colliderIndex)
{
var c = Colliders[colliderIndex];
var m = CurrentColliders[colliderIndex];
if (c.colliderType == BlittableColliderType.Capsule)
{
if (TryCollideCapsuleAndSphere(m.MultiplyPoint(c.offset), m.MultiplyPoint(c.tailOrNormal), c.radius,
pos, info.Settings.radius, out var l))
{
pos += l.GetDelta(c.radius);
}
}
else
{
if (TryCollideSphereAndSphere(m.MultiplyPoint(c.offset), c.radius,
pos, info.Settings.radius, out var l))
{
pos += l.GetDelta(c.radius);
}
}
StrandCollision[particleIndex] = pos;
}
}
}
/// <summary>
/// collide sphere a and sphere b.
/// move sphere b to resolved if collide.
/// </summary>
/// <param name="from"></param>
/// <param name="ra"></param>
/// <param name="to"></param>
/// <param name="ba"></param>
/// <param name="resolved"></param>
/// <returns></returns>
static bool TryCollideSphereAndSphere(
in Vector3 from, float ra,
in Vector3 to, float rb,
out LineSegment resolved
)
{
var d = Vector3.Distance(from, to);
if (d > (ra + rb))
{
resolved = default;
return false;
}
Vector3 normal = (to - from).normalized;
resolved = new(from, from + normal * (d - rb));
return true;
}
/// <summary>
/// collide capsule and sphere b.
/// move sphere b to resolved if collide.
/// </summary>
/// <param name="capsuleHead"></param>
/// <param name="capsuleTail"></param>
/// <param name="capsuleRadius"></param>
/// <param name="b"></param>
/// <param name="rb"></param>
static bool TryCollideCapsuleAndSphere(
in Vector3 capsuleHead,
in Vector3 capsuleTail,
float capsuleRadius,
in Vector3 b,
float rb,
out LineSegment resolved
)
{
var P = (capsuleTail - capsuleHead).normalized;
var Q = b - capsuleHead;
var dot = Vector3.Dot(P, Q);
if (dot <= 0)
{
// head側半球の球判定
return TryCollideSphereAndSphere(capsuleHead, capsuleRadius, b, rb, out resolved);
}
var t = dot / P.magnitude;
if (t >= 1.0f)
{
// tail側半球の球判定
return TryCollideSphereAndSphere(capsuleTail, capsuleRadius, b, rb, out resolved);
}
// head-tail上の m_transform.position との最近点
var p = capsuleHead + P * t;
return TryCollideSphereAndSphere(p, capsuleRadius, b, rb, out resolved);
}
}
public struct ClothCollisionJob : IJobParallelFor
{
// collider
[ReadOnly] public NativeArray<BlittableCollider> Colliders;
[ReadOnly] public NativeArray<Matrix4x4> CurrentColliders;
// particle
[ReadOnly] public NativeArray<TransformInfo> Info;
[ReadOnly] public NativeArray<Vector3> NextPositions;
[NativeDisableParallelForRestriction] public NativeArray<int> CollisionCount;
[NativeDisableParallelForRestriction] public NativeArray<Vector3> CollisionDelta;
// cloth
[ReadOnly] public NativeArray<(SpringConstraint, ClothRect)> ClothRects;
private void CollisionMove(int particleIndex, Vector3 delta)
{
CollisionCount[particleIndex] += 1;
CollisionDelta[particleIndex] += delta;
}
public void Execute(int rectIndex)
{
var (spring, rect) = ClothRects[rectIndex];
// using (new ProfileSample("Rect: Prepare"))
// _s0.BeginFrame();
// _s1.BeginFrame();
var a = NextPositions[rect._a];
var b = NextPositions[rect._b];
var c = NextPositions[rect._c];
var d = NextPositions[rect._d];
var aabb = GetBoundsFrom4(a, b, c, d);
// d x-x c
// |/
// a x
var _triangle1 = new Triangle(c, d, a);
// x c
// /|
// a x-x b
var _triangle0 = new Triangle(a, b, c);
for (int colliderIndex = 0; colliderIndex < Colliders.Length; ++colliderIndex)
{
var collider = Colliders[colliderIndex];
var collider_matrix = CurrentColliders[colliderIndex];
if (!aabb.Intersects(GetBounds(collider, collider_matrix)))
{
continue;
}
// 面の片側だけにヒットさせる
// 行き過ぎて戻るときに素通りする
// var p = _triangle0.Plane.ClosestPointOnPlane(col_pos);
// var dot = Vector3.Dot(_triangle0.Plane.normal, col_pos - p);
// if (_initialColliderNormalSide[collider] * dot < 0)
// {
// // 片側
// continue;
// }
if (TryCollide(collider, collider_matrix, _triangle0, out var l0))
{
CollisionMove(rect._a, l0.GetDelta(collider.radius));
CollisionMove(rect._b, l0.GetDelta(collider.radius));
CollisionMove(rect._c, l0.GetDelta(collider.radius));
}
if (TryCollide(collider, collider_matrix, _triangle1, out var l1))
{
CollisionMove(rect._c, l1.GetDelta(collider.radius));
CollisionMove(rect._d, l1.GetDelta(collider.radius));
CollisionMove(rect._a, l1.GetDelta(collider.radius));
}
}
}
static bool TryCollide(BlittableCollider collider, in Matrix4x4 colliderMatrix, in Triangle t, out LineSegment l)
{
var col_pos = colliderMatrix.MultiplyPoint(collider.offset);
if (collider.colliderType == BlittableColliderType.Capsule)
{
// capsule
var tail_pos = colliderMatrix.MultiplyPoint(collider.tailOrNormal);
var result = TriangleCapsuleCollisionSolver.Collide(t, new LineSegment(col_pos, tail_pos), collider.radius);
var type = result.TryGetClosest(out l);
return type.HasValue;
}
else
{
// sphere
return TryCollideSphere(t, col_pos, collider.radius, out l);
}
}
/// <summary>
///
/// </summary>
/// <param name="triangle"></param>
/// <param name="collider"></param>
/// <param name="radius"></param>
/// <returns>collider => 衝突点 への線分を返す</returns>
static bool TryCollideSphere(in Triangle triangle, in Vector3 collider, float radius, out LineSegment l)
{
var p = triangle.Plane.ClosestPointOnPlane(collider);
var distance = Vector3.Distance(p, collider);
if (distance > radius)
{
l = default;
return false;
}
if (triangle.IsSameSide(p))
{
l = new LineSegment(collider, p);
return true;
}
var (closestPoint, d) = triangle.GetClosest(collider);
if (d > radius)
{
l = default;
return false;
}
l = new LineSegment(collider, closestPoint);
return true;
}
public static Bounds GetBoundsFrom4(in Vector3 a, in Vector3 b, in Vector3 c, in Vector3 d)
{
var aabb = new Bounds(a, Vector3.zero);
aabb.Encapsulate(b);
aabb.Encapsulate(c);
aabb.Encapsulate(d);
return aabb;
}
public static Bounds GetBounds(BlittableCollider collider, Matrix4x4 m)
{
switch (collider.colliderType)
{
case BlittableColliderType.Capsule:
{
var h = m.MultiplyPoint(collider.offset);
var t = m.MultiplyPoint(collider.tailOrNormal);
var d = h - t;
var aabb = new Bounds((h + t) * 0.5f, new Vector3(Mathf.Abs(d.x), Mathf.Abs(d.y), Mathf.Abs(d.z)));
aabb.Expand(collider.radius * 2);
return aabb;
}
case BlittableColliderType.Sphere:
return new Bounds(m.MultiplyPoint(collider.offset), new Vector3(collider.radius, collider.radius, collider.radius));
default:
throw new NotImplementedException();
}
}
}
public struct CollisionApplyJob : IJobParallelFor
{
[ReadOnly] public NativeArray<bool> ClothUsedParticles;
[ReadOnly] public NativeArray<Vector3> StrandCollision;
[ReadOnly] public NativeArray<int> ClothCollisionCount;
[ReadOnly] public NativeArray<Vector3> ClothCollisionDelta;
[NativeDisableParallelForRestriction] public NativeArray<Vector3> NextPosition;
public void Execute(int particleIndex)
{
if (ClothUsedParticles[particleIndex])
{
if (ClothCollisionCount[particleIndex] > 0)
{
NextPosition[particleIndex] += (ClothCollisionDelta[particleIndex] / ClothCollisionCount[particleIndex]);
}
}
else
{
NextPosition[particleIndex] = StrandCollision[particleIndex];
}
}
}
}