public void Dispose()
{
if (surfaceLoaded && bitmap != null)
{
bitmap.Dispose();
surfaceLoaded = false;
}
freeParticles.Clear();
ActiveParticles.Clear();
}
//===========================================================
// Particle System Update Functions
//===========================================================
/// <summary>
/// Sorts the particles to draw particles furthest from the camera first, in order to achieve proper depth perspective.
///
/// <para>NOTE: This operation is very expensive and should only be used when you are
/// drawing particles with both opaque and semi-transparent portions, and not using additive blending.</para>
/// <para>Merge Sort is the sorting algorithm used, as it tends to be best for linked lists.
/// TODO - WHILE MERGE SORT SHOULD BE USED, DUE TO TIME CONSTRAINTS A (PROBABLY) SLOWER METHOD (QUICK-SORT)
/// IS BEING USED INSTEAD. THIS FUNCTION NEEDS TO BE UPDATED TO USE MERGE SORT STILL.
/// THE LINKED LIST MERGE SORT ALGORITHM CAN BE FOUND AT http://www.chiark.greenend.org.uk/~sgtatham/algorithms/listsort.html</para>
/// </summary>
/// <param name="fElapsedTimeInSeconds">How long it has been since the last update</param>
protected void UpdateParticleSystemToSortParticlesByDistanceFromCamera(float fElapsedTimeInSeconds)
{
// Store the Number of Active Particles to sort
int iNumberOfActiveParticles = ActiveParticles.Count;
// If there is nothing to sort
if (iNumberOfActiveParticles <= 1)
{
// Exit without sorting
return;
}
// Create a List to put the Active Particles in to be sorted
List <Particle> cActiveParticleList = new List <Particle>(iNumberOfActiveParticles);
// Add all of the Particles to the List
LinkedListNode <Particle> cNode = ActiveParticles.First;
while (cNode != null)
{
// Copy this Particle into the Array
cActiveParticleList.Add(cNode.Value);
// Move to the next Active Particle
cNode = cNode.Next;
}
// Now that the List is full, sort it
cActiveParticleList.Sort(delegate(Particle Particle1, Particle Particle2)
{
DefaultSprite3DBillboardParticle cParticle1 = (DefaultSprite3DBillboardParticle)(DPSFParticle)Particle1;
DefaultSprite3DBillboardParticle cParticle2 = (DefaultSprite3DBillboardParticle)(DPSFParticle)Particle2;
return(cParticle1.DistanceFromCameraSquared.CompareTo(cParticle2.DistanceFromCameraSquared));
});
// Now that the List is sorted, add the Particles into the Active Particles Linked List in sorted order
ActiveParticles.Clear();
for (int iIndex = 0; iIndex < iNumberOfActiveParticles; iIndex++)
{
// Add this Particle to the Active Particles Linked List.
// List is sorted from smallest to largest, but we want
// our Linked List sorted from largest to smallest, since
// the Particles at the end of the Linked List are drawn last.
ActiveParticles.AddFirst(cActiveParticleList[iIndex]);
}
}