private bool InitializeParticle(Particle p)
{
Color4 color;
Matrix32 transform;
CalcInitialColorAndTransform(out color, out transform);
float emitterScaleAmount = 1;
Vector2 emitterScale = new Vector2();
emitterScale.X = transform.U.Length;
emitterScale.Y = transform.V.Length;
float crossProduct = Vector2.CrossProduct(transform.U, transform.V);
if (crossProduct < 0.0f)
{
emitterScale.Y = -emitterScale.Y;
}
emitterScaleAmount = Mathf.Sqrt(Math.Abs(crossProduct));
float emitterAngle = transform.U.Atan2Deg;
NumericRange aspectRatioVariationPair = new NumericRange(0, Math.Max(0.0f, AspectRatio.Dispersion));
float zoom = Zoom.NormalRandomNumber(Rng);
float aspectRatio = AspectRatio.Median *
(1 + Math.Abs(aspectRatioVariationPair.NormalRandomNumber(Rng))) /
(1 + Math.Abs(aspectRatioVariationPair.NormalRandomNumber(Rng)));
p.TextureIndex = 0.0f;
p.Velocity = Velocity.NormalRandomNumber(Rng) * emitterScaleAmount;
p.ScaleInitial = emitterScale * ApplyAspectRatio(zoom, aspectRatio);
p.ScaleCurrent = p.ScaleInitial;
p.WindDirection = WindDirection.UniformRandomNumber(Rng);
p.WindAmount = WindAmount.NormalRandomNumber(Rng) * emitterScaleAmount;
p.GravityVelocity = 0.0f;
p.GravityAcceleration = 0.0f;
p.GravityAmount = GravityAmount.NormalRandomNumber(Rng) * emitterScaleAmount;
p.GravityDirection = GravityDirection.NormalRandomNumber(Rng);
p.MagnetAmountInitial = MagnetAmount.NormalRandomNumber(Rng);
p.Lifetime = Math.Max(Lifetime.NormalRandomNumber(Rng), 0.1f);
p.Age = 0.0f;
p.AngularVelocity = AngularVelocity.NormalRandomNumber(Rng);
p.Angle = Orientation.UniformRandomNumber(Rng) + emitterAngle;
p.Spin = Spin.NormalRandomNumber(Rng);
p.ColorInitial = color;
p.ColorCurrent = color;
p.RandomRayDirection = (new NumericRange(0, 360)).UniformRandomNumber(Rng);
p.RandomSplineVertex0 = GenerateRandomMotionControlPoint(ref p.RandomRayDirection);
p.RandomSplineVertex1 = Vector2.Zero;
p.RandomSplineVertex2 = GenerateRandomMotionControlPoint(ref p.RandomRayDirection);
p.RandomSplineVertex3 = GenerateRandomMotionControlPoint(ref p.RandomRayDirection);
p.RandomMotionSpeed = RandomMotionSpeed.NormalRandomNumber(Rng);
p.RandomSplineOffset = 0;
Vector2 position;
switch (Shape)
{
case EmitterShape.Point:
position = 0.5f * Size;
p.RegularDirection = Direction.UniformRandomNumber(Rng) + emitterAngle - 90.0f;
break;
case EmitterShape.Line:
position = new Vector2(Rng.RandomFloat() * Size.X, Size.Y * 0.5f);
p.RegularDirection = Direction.UniformRandomNumber(Rng) + emitterAngle - 90.0f;
break;
case EmitterShape.Ellipse:
float angle = Rng.RandomFloat(0, 360);
Vector2 sincos = Vector2.CosSinRough(angle * Mathf.DegToRad);
position = 0.5f * ((sincos + Vector2.One) * Size);
p.RegularDirection = Direction.UniformRandomNumber(Rng) + emitterAngle - 90 + angle;
break;
case EmitterShape.Area:
position.X = Rng.RandomFloat() * Size.X;
position.Y = Rng.RandomFloat() * Size.Y;
p.RegularDirection = Direction.UniformRandomNumber(Rng) + emitterAngle - 90.0f;
break;
case EmitterShape.Custom:
position = GetPointInCustomShape();
p.RegularDirection = Direction.UniformRandomNumber(Rng) + emitterAngle - 90.0f;
break;
default:
throw new Lime.Exception("Invalid particle emitter shape");
}
p.RegularPosition = transform.TransformVector(position);
if (!TryGetRandomModifier(out p.Modifier))
{
return(false);
}
var animationDuration = AnimationUtils.FramesToSeconds(p.Modifier.Animators.GetOverallDuration());
p.AgeToAnimationTime = (float)(animationDuration / p.Lifetime);
if (EmissionType == EmissionType.Inner)
{
p.RegularDirection += 180;
}
else if ((EmissionType & EmissionType.Inner) != 0)
{
if (Rng.RandomInt(2) == 0)
{
p.RegularDirection += 180;
}
}
else if (EmissionType == 0)
{
return(false);
}
p.FullDirection = p.RegularDirection;
p.FullPosition = p.RegularPosition;
return(true);
}