public AngleConstraint2D makeAngleConstraint(Spring2D s1, Spring2D s2)
{
AngleConstraint2D angle = new AngleConstraint2D(this, s1, s2);
angles.Add(angle);
return(angle);
}
public Spring2D makeSpring(Particle2D a, Particle2D b)
{
float r = Vector2.Distance(a.Position, b.Position);
Spring2D s = new Spring2D(this, a, b, r);
springs.Add(s);
return(s);
}
void applyConstraints()
{
//gravity
if (setting.gravity != Vector2.zero)
{
for (int i = 0; i < sim.numberOfParticles(); ++i)
{
p = sim.getParticle(i);
if (p.IsFree)
{
p.Position += setting.gravity;
}
}
}
//iterations
for (int iter = 0; iter < setting.iteration; iter++)
{
if (setting.applyString)
{
for (int p = 1; p <= sim.maxSpringConvergenceID; p++)
{
for (int i = 0; i < sim.numberOfSprings(); i++)
{
Spring2D sp = sim.getSpring(i);
if (sp.convergenceGroupID == p)
{
sp.apply();
}
}
}
}
if (setting.applyAngle)
{
for (int p = 1; p <= sim.maxAngleConvergenceID; p++)
{
for (int i = 0; i < sim.numberOfAngleConstraints(); i++)
{
AngleConstraint2D ag = sim.getAngleConstraint(i);
if (ag.convergenceGroupID == p)
{
ag.GetDelta();
}
}
for (int i = 0; i < sim.numberOfAngleConstraints(); i++)
{
AngleConstraint2D ag = sim.getAngleConstraint(i);
if (ag.convergenceGroupID == p)
{
ag.apply();
}
}
}
}
}
}
public void removeSpring(Spring2D a)
{
for (int i = angles.Count - 1; i >= 0; i--)
{
if (angles[i].ContainSpring(a))
{
angles.RemoveAt(i);
}
}
springs.Remove(a);
}
public void removeParticle(Particle2D p)
{
for (int i = springs.Count - 1; i >= 0; i--)
{
if (springs[i].ParticleA == p || springs[i].ParticleB == p)
{
Spring2D s = springs[i];
removeSpring(s);
}
}
particles.Remove(p);
}
//setup by sticks
//only b rotates around m, if you need a rotate around m, just make another angle constraint
public AngleConstraint2D(Simulation sim, Spring2D _spring1, Spring2D _spring2)
{
this.on = true;
this.sim = sim;
if (_spring1.ParticleA == _spring2.ParticleA)
{
SetTopology(_spring1.ParticleB, _spring1.ParticleA, _spring2.ParticleB); return;
}
if (_spring1.ParticleA == _spring2.ParticleB)
{
SetTopology(_spring1.ParticleB, _spring1.ParticleA, _spring2.ParticleA); return;
}
if (_spring1.ParticleB == _spring2.ParticleA)
{
SetTopology(_spring1.ParticleA, _spring1.ParticleB, _spring2.ParticleB); return;
}
if (_spring1.ParticleB == _spring2.ParticleB)
{
SetTopology(_spring1.ParticleA, _spring1.ParticleB, _spring2.ParticleA); return;
}
}
public SimBuffer_Spring(Simulation sim, Vector2[] particleUV, int width, int height)
{
this.sim = sim;
rt = new RenderTexture[sim.maxSpringConvergenceID];
int parNum = sim.numberOfParticles();
ID_SpringParamRT = Shader.PropertyToID("_SpringParamRT");
ID_SpringConstant = Shader.PropertyToID("_SpringConstant");
ID_PositionRT = Shader.PropertyToID("_PositionRT");
//rg = the other end point's uv, b = restlength, a = state
Color[] tempColor = new Color[width * height];
Texture2D tempTex = new Texture2D(width, height, TextureFormat.RGBAFloat, false, false);
for (int i = 0; i < sim.maxSpringConvergenceID; i++)
{
//init rt
rt[i] = new RenderTexture(width, height, 0, RTFormat.ARGB);
rt[i].Create();
//prepare temp color
for (int k = 0; k < width * height; k++)
{
if (k < parNum)
{
Vector2 uv = particleUV[k];
tempColor[k] = new Color(uv.x, uv.y, 1f, (sim.getParticle(k).IsFree) ? 1f : 0f);
}
else
{
tempColor[k] = new Color(0f, 0f, 1f, 0f);
}
}
//get info
for (int j = 0; j < sim.numberOfSprings(); j++)
{
Spring2D sp = sim.getSpring(j);
if (sp.convergenceGroupID == i + 1)
{
int a = sim.getParticleIndex(sp.ParticleA);
int b = sim.getParticleIndex(sp.ParticleB);
tempColor[a].r = particleUV[b].x;
tempColor[a].g = particleUV[b].y;
tempColor[a].b = sp.restLength2;
tempColor[a].a = (sp.ParticleA.IsFree) ? 1f : 0f;
tempColor[b].r = particleUV[a].x;
tempColor[b].g = particleUV[a].y;
tempColor[b].b = sp.restLength2;
tempColor[b].a = (sp.ParticleB.IsFree) ? 1f : 0f;
}
}
//blit
tempTex.SetPixels(tempColor);
tempTex.Apply();
Graphics.Blit(tempTex, rt[i]);
}
Extension.ObjDestroy(tempTex);
//mpb
mpb = new MaterialPropertyBlock[sim.maxSpringConvergenceID];
for (int i = 0; i < sim.maxSpringConvergenceID; i++)
{
mpb[i] = new MaterialPropertyBlock();
mpb[i].SetTexture(ID_SpringParamRT, rt[i]);
mpb[i].SetFloat(ID_SpringConstant, sim.Settings.springConstant);
}
//tempRT
tempRT = new RenderTexture[sim.maxSpringConvergenceID - 1];
}
/// <summary>
/// Calculates the convergence ID of the springs and angles that are connected to particle specified by particleIndex
/// </summary>
/// <param name="particleIndex">Particle index.</param>
private void CalcConvergenceID(int particleIndex)
{
Particle2D pp = this.getParticle(particleIndex);
//Spring
List <Spring2D> sp = new List <Spring2D> (10); //the conencted spring for particle index
int springNum = this.numberOfSprings();
//get the connected spring
for (int i = 0; i < springNum; i++)
{
Spring2D s = this.getSpring(i);
Particle2D a = s.ParticleA;
Particle2D b = s.ParticleB;
if (a == pp || b == pp)
{
sp.Add(s);
}
}
//calc the convergence id for the springs which connects to this particle
List <int> IDinUse = new List <int> (10);
for (int i = 0; i < sp.Count; i++)
{
if (sp[i].convergenceGroupID != 0)
{
IDinUse.Add(sp[i].convergenceGroupID);
}
}
for (int i = 0; i < sp.Count; i++)
{
if (sp[i].convergenceGroupID == 0)
{
int id = 1;
while (IDinUse.Contains(id))
{
id++;
}
sp[i].convergenceGroupID = id;
IDinUse.Add(id);
if (id > this.maxSpringConvergenceID)
{
this.maxSpringConvergenceID = id;
}
}
}
//angle
List <AngleConstraint2D> ag = new List <AngleConstraint2D> (10);
int angleNum = this.numberOfAngleConstraints();
//get the connected angles
for (int i = 0; i < angleNum; i++)
{
AngleConstraint2D angle = this.getAngleConstraint(i);
Particle2D b = angle.ParticleB;
Particle2D m = angle.ParticleM;
if (b == pp || m == pp)
{
ag.Add(angle);
}
}
//recalc the convergence id for the angles that are connected to this particle
IDinUse.Clear();
for (int i = 0; i < ag.Count; i++)
{
if (ag[i].convergenceGroupID != 0)
{
IDinUse.Add(ag[i].convergenceGroupID);
}
}
for (int i = 0; i < ag.Count; i++)
{
if (ag[i].convergenceGroupID == 0)
{
int id = 1;
while (IDinUse.Contains(id))
{
id++;
}
ag[i].convergenceGroupID = id;
IDinUse.Add(id);
if (id > this.maxAngleConvergenceID)
{
this.maxAngleConvergenceID = id;
}
}
}
}
public bool ContainSpring(Spring2D spring)
{
return(ContainParticle(spring.ParticleA) && ContainParticle(spring.ParticleB));
}