public static Matrix MatrixFromParticle(Particle particle)
{
Matrix rot = Matrix.CreateRotationZ(particle.Angle);
Matrix bill = Matrix.CreateBillboard(particle.Position, _camera.Position, _camera.UpVector, null);
Matrix noTransBill = bill;
noTransBill.Translation = Vector3.Zero;
Matrix worldRot = Matrix.CreateScale(particle.Scale) * rot * noTransBill;
worldRot.Translation = bill.Translation;
return worldRot;
}
public void Trigger(int num, Vector3 origin, Color tint)
{
for(int i = 0; i < num; i++)
{
if(Particles.Count < Data.MaxParticles)
{
Particle toAdd = new Particle();
bool sampleFound = false;
Vector3 sample = new Vector3(99999, 99999, 9999);
while(!sampleFound)
{
sample = RandVec(Data.EmissionRadius);
if(sample.Length() < Data.EmissionRadius)
{
sampleFound = true;
}
}
toAdd.Position = sample + origin;
toAdd.Velocity = (sample);
toAdd.Velocity.Normalize();
toAdd.Velocity *= Data.EmissionSpeed;
toAdd.Scale = Rand(Data.MinScale, Data.MaxScale);
toAdd.Angle = Rand(Data.MinAngle, Data.MaxAngle);
toAdd.AngularVelocity = Rand(Data.MinAngular, Data.MaxAngular);
toAdd.LifeRemaining = 1.0f;
toAdd.Tint = tint;
toAdd.InstanceData = new InstanceData(Matrix.Identity, toAdd.Tint, true);
Particles.Add(toAdd);
if(toAdd.InstanceData != null)
{
Sprites.Add(toAdd.InstanceData);
}
}
}
}
public static int CompareZDepth(Particle A, Particle B)
{
if(A == B)
{
return 0;
}
if((_camera.Position - A.Position).LengthSquared() < (_camera.Position - B.Position).LengthSquared())
{
return 1;
}
else
{
return -1;
}
}