bounce/examples/testbed/tests/cloth_tearing.h

571 lines
12 KiB
C++

/*
* Copyright (c) 2016-2019 Irlan Robson https://irlanrobson.github.io
*
* This software is provided 'as-is', without any express or implied
* warranty. In no event will the authors be held liable for any damages
* arising from the use of this software.
* Permission is granted to anyone to use this software for any purpose,
* including commercial applications, and to alter it and redistribute it
* freely, subject to the following restrictions:
* 1. The origin of this software must not be misrepresented; you must not
* claim that you wrote the original software. If you use this software
* in a product, an acknowledgment in the product documentation would be
* appreciated but is not required.
* 2. Altered source versions must be plainly marked as such, and must not be
* misrepresented as being the original software.
* 3. This notice may not be removed or altered from any source distribution.
*/
#ifndef CLOTH_TEARING_H
#define CLOTH_TEARING_H
class ClothTearing : public Test
{
public:
enum
{
e_w = 10,
e_h = 10
};
ClothTearing()
{
g_camera->m_zoom = 20.0f;
b3GridClothMesh<e_w, e_h> m;
b3ClothParticle** particles = (b3ClothParticle * *)b3Alloc(m.vertexCount * sizeof(b3ClothParticle*));
for (u32 i = 0; i < m.vertexCount; ++i)
{
b3ClothParticleDef pd;
pd.type = e_dynamicClothParticle;
pd.position = m.vertices[i];
b3ClothParticle* p = m_cloth.CreateParticle(pd);
particles[i] = p;
b3ClothSphereShapeDef sd;
sd.p = p;
sd.radius = 0.2f;
sd.friction = 0.4f;
m_cloth.CreateSphereShape(sd);
}
for (u32 i = 0; i < m.triangleCount; ++i)
{
u32 v1 = m.triangles[i].v1;
u32 v2 = m.triangles[i].v2;
u32 v3 = m.triangles[i].v3;
b3ClothParticle* p1 = particles[v1];
b3ClothParticle* p2 = particles[v2];
b3ClothParticle* p3 = particles[v3];
b3ClothTriangleShapeDef tsd;
tsd.p1 = p1;
tsd.p2 = p2;
tsd.p3 = p3;
tsd.v1 = m.vertices[v1];
tsd.v2 = m.vertices[v2];
tsd.v3 = m.vertices[v3];
tsd.density = 0.1f;
m_cloth.CreateTriangleShape(tsd);
{
b3SpringForceDef sfd;
sfd.Initialize(p1, p2, 1000.0f, 10.0f);
CreateSpringForce(sfd);
}
{
b3SpringForceDef sfd;
sfd.Initialize(p2, p3, 1000.0f, 10.0f);
CreateSpringForce(sfd);
}
{
b3SpringForceDef sfd;
sfd.Initialize(p3, p1, 1000.0f, 10.0f);
CreateSpringForce(sfd);
}
}
for (u32 i = 0; i < e_w + 1; ++i)
{
u32 vertex = m.GetVertex(0, i);
particles[vertex]->SetType(e_staticClothParticle);
}
b3Free(particles);
m_cloth.SetGravity(b3Vec3(0.0f, -9.8f, 0.0f));
m_clothDragger = new b3ClothDragger(&m_ray, &m_cloth);
m_clothDragger->SetStaticDrag(false);
}
~ClothTearing()
{
delete m_clothDragger;
}
b3SpringForce* FindSpringForce(b3ClothParticle* p1, b3ClothParticle* p2)
{
for (b3Force* f = m_cloth.GetForceList().m_head; f; f = f->GetNext())
{
if (f->GetType() != e_springForce)
{
continue;
}
b3SpringForce* sf = (b3SpringForce*)f;
b3ClothParticle* sp1 = sf->GetParticle1();
b3ClothParticle* sp2 = sf->GetParticle2();
if (sp1 == p1 && sp2 == p2)
{
return sf;
}
if (sp1 == p2 && sp2 == p1)
{
return sf;
}
}
return nullptr;
}
b3SpringForce* CreateSpringForce(const b3SpringForceDef& def)
{
b3SpringForce* sf = FindSpringForce(def.p1, def.p2);
if (sf != nullptr)
{
return sf;
}
return (b3SpringForce*)m_cloth.CreateForce(def);
}
void DrawSpringForces()
{
for (b3Force* f = m_cloth.GetForceList().m_head; f; f = f->GetNext())
{
if (f->GetType() != e_springForce)
{
continue;
}
b3SpringForce* s = (b3SpringForce*)f;
b3ClothParticle* p1 = s->GetParticle1();
b3ClothParticle* p2 = s->GetParticle2();
g_draw->DrawSegment(p1->GetPosition(), p2->GetPosition(), b3Color_black);
}
}
void Partition(b3ClothParticle* p, const b3Plane& plane,
b3Array<b3ClothTriangleShape*>& above,
b3Array<b3ClothTriangleShape*>& below)
{
for (b3ClothTriangleShape* t = m_cloth.GetTriangleShapeList().m_head; t; t = t->GetNext())
{
b3ClothParticle* p1 = t->GetParticle1();
b3ClothParticle* p2 = t->GetParticle2();
b3ClothParticle* p3 = t->GetParticle3();
if (p1 != p && p2 != p && p3 != p)
{
continue;
}
b3Vec3 x1 = p1->GetPosition();
b3Vec3 x2 = p2->GetPosition();
b3Vec3 x3 = p3->GetPosition();
b3Vec3 center = (x1 + x2 + x3) / 3.0f;
scalar distance = b3Distance(center, plane);
if (distance > 0.0f)
{
above.PushBack(t);
}
else
{
below.PushBack(t);
}
}
}
bool HasSpring(const b3Array<b3ClothTriangleShape*>& triangles,
b3ClothParticle* pOld, b3ClothParticle* pOther)
{
for (u32 i = 0; i < triangles.Count(); ++i)
{
b3ClothTriangleShape* triangle = triangles[i];
b3ClothParticle* tp1 = triangle->GetParticle1();
b3ClothParticle* tp2 = triangle->GetParticle2();
b3ClothParticle* tp3 = triangle->GetParticle3();
// 1, 2
if (tp1 == pOld && tp2 == pOther)
{
return true;
}
// 2, 1
if (tp2 == pOld && tp1 == pOther)
{
return true;
}
// 2, 3
if (tp2 == pOld && tp3 == pOther)
{
return true;
}
// 3, 2
if (tp3 == pOld && tp2 == pOther)
{
return true;
}
// 3, 1
if (tp3 == pOld && tp1 == pOther)
{
return true;
}
// 1, 3
if (tp1 == pOld && tp3 == pOther)
{
return true;
}
}
return false;
}
bool SplitParticle(b3ClothParticle* pOld, const b3Plane& plane)
{
// Collect triangles.
b3StackArray<b3ClothTriangleShape*, 32> trianglesAbove, trianglesBelow;
Partition(pOld, plane, trianglesAbove, trianglesBelow);
// There must be at least one triangle on each side of the plane.
if (trianglesAbove.Count() == 0 || trianglesBelow.Count() == 0)
{
return false;
}
b3ClothParticleDef pdNew;
pdNew.type = pOld->GetType();
pdNew.position = pOld->GetPosition() - 0.2f * plane.normal;
b3ClothParticle* pNew = m_cloth.CreateParticle(pdNew);
b3ClothSphereShapeDef ssdNew;
ssdNew.p = pNew;
ssdNew.radius = 0.2f;
ssdNew.friction = 0.4f;
m_cloth.CreateSphereShape(ssdNew);
for (u32 i = 0; i < trianglesBelow.Count(); ++i)
{
b3ClothTriangleShape* triangle = trianglesBelow[i];
b3ClothParticle* p1 = triangle->GetParticle1();
b3ClothParticle* p2 = triangle->GetParticle2();
b3ClothParticle* p3 = triangle->GetParticle3();
m_cloth.DestroyTriangleShape(triangle);
if (p1 == pOld)
{
b3ClothTriangleShapeDef tdNew;
tdNew.p1 = pNew;
tdNew.p2 = p2;
tdNew.p3 = p3;
tdNew.v1 = pNew->GetPosition();
tdNew.v2 = p2->GetPosition();
tdNew.v3 = p3->GetPosition();
m_cloth.CreateTriangleShape(tdNew);
b3SpringForce* sf1 = FindSpringForce(p1, p2);
if (sf1)
{
b3SpringForceDef sNew;
sNew.p1 = pNew;
sNew.p2 = p2;
sNew.restLength = sf1->GetRestLenght();
sNew.structural = sf1->GetStructuralStiffness();
sNew.damping = sf1->GetDampingStiffness();
m_cloth.CreateForce(sNew);
if (HasSpring(trianglesAbove, p1, p2) == false)
{
m_cloth.DestroyForce(sf1);
}
}
b3SpringForce* sf2 = FindSpringForce(p3, p1);
if (sf2)
{
b3SpringForceDef sNew;
sNew.p1 = p3;
sNew.p2 = pNew;
sNew.restLength = sf2->GetRestLenght();
sNew.structural = sf2->GetStructuralStiffness();
sNew.damping = sf2->GetDampingStiffness();
m_cloth.CreateForce(sNew);
if (HasSpring(trianglesAbove, p3, p1) == false)
{
m_cloth.DestroyForce(sf2);
}
}
}
if (p2 == pOld)
{
b3ClothTriangleShapeDef tdNew;
tdNew.p1 = p1;
tdNew.p2 = pNew;
tdNew.p3 = p3;
tdNew.v1 = p1->GetPosition();
tdNew.v2 = pNew->GetPosition();
tdNew.v3 = p3->GetPosition();
m_cloth.CreateTriangleShape(tdNew);
b3SpringForce* sf1 = FindSpringForce(p1, p2);
if (sf1)
{
b3SpringForceDef sNew;
sNew.p1 = p1;
sNew.p2 = pNew;
sNew.restLength = sf1->GetRestLenght();
sNew.structural = sf1->GetStructuralStiffness();
sNew.damping = sf1->GetDampingStiffness();
m_cloth.CreateForce(sNew);
if (HasSpring(trianglesAbove, p1, p2) == false)
{
m_cloth.DestroyForce(sf1);
}
}
b3SpringForce* sf2 = FindSpringForce(p2, p3);
if (sf2)
{
b3SpringForceDef sNew;
sNew.p1 = pNew;
sNew.p2 = p3;
sNew.restLength = sf2->GetRestLenght();
sNew.structural = sf2->GetStructuralStiffness();
sNew.damping = sf2->GetDampingStiffness();
m_cloth.CreateForce(sNew);
if (HasSpring(trianglesAbove, p2, p3) == false)
{
m_cloth.DestroyForce(sf2);
}
}
}
if (p3 == pOld)
{
b3ClothTriangleShapeDef tdNew;
tdNew.p1 = p1;
tdNew.p2 = p2;
tdNew.p3 = pNew;
tdNew.v1 = p1->GetPosition();
tdNew.v2 = p2->GetPosition();
tdNew.v3 = pNew->GetPosition();
m_cloth.CreateTriangleShape(tdNew);
b3SpringForce* sf1 = FindSpringForce(p2, p3);
if (sf1)
{
b3SpringForceDef sNew;
sNew.p1 = p2;
sNew.p2 = pNew;
sNew.restLength = sf1->GetRestLenght();
sNew.structural = sf1->GetStructuralStiffness();
sNew.damping = sf1->GetDampingStiffness();
m_cloth.CreateForce(sNew);
if (HasSpring(trianglesAbove, p2, p3) == false)
{
m_cloth.DestroyForce(sf1);
}
}
b3SpringForce* sf2 = FindSpringForce(p3, p1);
if (sf2)
{
b3SpringForceDef sNew;
sNew.p1 = pNew;
sNew.p2 = p1;
sNew.restLength = sf2->GetRestLenght();
sNew.structural = sf2->GetStructuralStiffness();
sNew.damping = sf2->GetDampingStiffness();
m_cloth.CreateForce(sNew);
if (HasSpring(trianglesAbove, p3, p1) == false)
{
m_cloth.DestroyForce(sf2);
}
}
}
}
return true;
}
bool Tear()
{
b3Force* f = m_cloth.GetForceList().m_head;
while (f)
{
if (f->GetType() != e_springForce)
{
f = f->GetNext();
continue;
}
b3SpringForce* s = (b3SpringForce*)f;
f = f->GetNext();
b3Vec3 tension = s->GetActionForce();
const scalar kMaxTension = 1000.0f;
if (b3LengthSquared(tension) <= kMaxTension * kMaxTension)
{
continue;
}
b3ClothParticle* p1 = s->GetParticle1();
b3ClothParticle* p2 = s->GetParticle2();
b3Vec3 x1 = p1->GetPosition();
b3Vec3 x2 = p2->GetPosition();
if (p1->GetType() == e_dynamicClothParticle)
{
b3Vec3 n = b3Normalize(x2 - x1);
b3Plane plane(n, x1);
bool wasSplit = SplitParticle(p1, plane);
if (wasSplit)
{
return true;
}
}
if (p2->GetType() == e_dynamicClothParticle)
{
b3Vec3 n = b3Normalize(x1 - x2);
b3Plane plane(n, x2);
bool wasSplit = SplitParticle(p2, plane);
if (wasSplit)
{
return true;
}
}
}
return false;
}
void Step()
{
Test::Step();
m_cloth.Step(g_testSettings->inv_hertz, g_testSettings->velocityIterations, g_testSettings->positionIterations);
while (Tear());
m_cloth.Draw();
DrawSpringForces();
if (m_clothDragger->IsDragging())
{
b3Vec3 pA = m_clothDragger->GetPointA();
b3Vec3 pB = m_clothDragger->GetPointB();
g_draw->DrawPoint(pA, 4.0f, b3Color_green);
g_draw->DrawPoint(pB, 4.0f, b3Color_green);
g_draw->DrawSegment(pA, pB, b3Color_white);
}
extern u32 b3_clothSolverIterations;
g_draw->DrawString(b3Color_white, "Iterations = %d", b3_clothSolverIterations);
scalar E = m_cloth.GetEnergy();
g_draw->DrawString(b3Color_white, "E = %f", E);
}
void MouseMove(const b3Ray3& pw)
{
Test::MouseMove(pw);
if (m_clothDragger->IsDragging() == true)
{
m_clothDragger->Drag();
}
}
void MouseLeftDown(const b3Ray3& pw)
{
Test::MouseLeftDown(pw);
if (m_clothDragger->IsDragging() == false)
{
m_clothDragger->StartDragging();
}
}
void MouseLeftUp(const b3Ray3& pw)
{
Test::MouseLeftUp(pw);
if (m_clothDragger->IsDragging() == true)
{
m_clothDragger->StopDragging();
}
}
static Test* Create()
{
return new ClothTearing();
}
b3Cloth m_cloth;
b3ClothDragger* m_clothDragger;
};
#endif