private static ParticleData UpdateVelocity(ParticleData particle, float relAge)
{
if (relAge < 0.25f)
{
if (particle.Velocity.Y < 0.0f)
{
particle.Velocity.Y += -0.5f;
}
else
{
particle.Velocity.Y += 0.5f;
}
if (particle.Velocity.X < 0.0f)
{
particle.Velocity.X += -0.05f;
}
else
{
particle.Velocity.X += 0.05f;
}
}
else if (relAge >= 0.25f && relAge < 0.75f)
{
if (particle.Velocity.Y < 0.0f)
{
particle.Velocity.Y += -0.25f;
}
else
{
particle.Velocity.Y += 0.25f;
}
if (particle.Velocity.X < 0.0f)
{
particle.Velocity.X += 0.25f;
}
else
{
particle.Velocity.X += -0.25f;
}
}
else if (relAge >= 0.75f)
{
if (particle.PlayerCollision)
{
particle.Velocity.X += -0.5f;
}
else
{
particle.Velocity.X += 0.5f;
}
}
particle.Position += particle.Velocity;
return particle;
}
public static ParticleData UpdateParticle(ParticleData particle, GameTime gameTime)
{
float now = (float)gameTime.TotalGameTime.TotalMilliseconds;
float timeAlive = now - particle.BirthTime;
float relAge = timeAlive / particle.MaxAge;
// TODO: Need to figure out here how to manipulate velocity to get desired shape and speed, and later on, color
return UpdateColor(UpdateVelocity(particle, relAge), relAge);
}
private static ParticleData UpdateColor(ParticleData particle, float relAge)
{
if (relAge < 0.25f)
{
particle.ModColor = Color.White;
}
else if (relAge >= 0.25f && relAge < 0.75f)
{
particle.ModColor.G -= 6;
particle.ModColor.B -= 9;
}
return particle;
}
private void AddExplosionParticle(Vector2 explosionPos, float maxAge, bool playerCollision, GameTime gameTime)
{
var particle = new ParticleData();
particle.OriginalPosition = explosionPos;
particle.Position = particle.OriginalPosition;
//particle.BirthTime = (float)gameTime.TotalGameTime.TotalMilliseconds;
particle.MaxAge = maxAge;
particle.Scaling = 1.0f;
particle.ModColor = Color.White;
particle.Angle = 0.0f;
// generate random angle in a range (or set of ranges) to be determined later
float baseAngle = (float)_rng.NextDouble() * 20.0f + 32.5f;
Vector2 baseVelocity = new Vector2(10.0f, 0.0f);
bool upDirection = _rng.Next() % 2 == 0;
if (upDirection && playerCollision)
{
particle.Velocity = Vector2.Transform(baseVelocity, Matrix.CreateRotationZ(MathHelper.ToRadians(baseAngle)));
}
else if (playerCollision)
{
particle.Velocity = Vector2.Transform(baseVelocity, Matrix.CreateRotationZ(MathHelper.ToRadians(-baseAngle)));
}
else if (!upDirection && !playerCollision)
{
particle.Velocity = Vector2.Transform(baseVelocity, Matrix.CreateRotationZ(MathHelper.ToRadians(180.0f - baseAngle)));
}
else
{
particle.Velocity = Vector2.Transform(baseVelocity, Matrix.CreateRotationZ(MathHelper.ToRadians(180.0f + baseAngle)));
}
particle.PlayerCollision = playerCollision;
ParticleQueue.Enqueue(particle);
}