private void Init(Type[] types)
{
this.types = types;
usageIndices = new byte[types.Length];
int index = 0;
VertexElement[] vertexElements = new VertexElement[types.Length];
semantics = new Semantic[types.Length];
SortedList usages = new SortedList( );
foreach (Type type in types)
{
VertexElement element = StreamFactory.Instance.VertexElement(type);
element.Stream = (short)index;
element.Offset = 0;
if (!usages.Contains(element.DeclarationUsage))
{
usages[element.DeclarationUsage] = (byte)0;
}
element.UsageIndex = usageIndices[index] = (byte)usages[element.DeclarationUsage];
usages[element.DeclarationUsage] = (byte)((byte)usages[element.DeclarationUsage] + 1);
vertexElements[index] = element;
semantics[index] = new Semantic(element.DeclarationUsage, element.UsageIndex);
index++;
}
vertexDeclaration = Device.Instance.CreateVertexDeclaration(vertexElements);
}
/// <summary>
/// Returns the index of the <see cref="IVertexStream"/> for a given <see cref="Semantic"/> description.
/// </summary>
/// <param name="sem">The <see cref="Semantic"/> to get stream for.</param>
/// <returns>The index of the <see cref="IVertexStream"/> for a given <see cref="Semantic"/> description.</returns>
public int GetIndex(Semantic sem)
{
int counter = 0;
for (int i = 0; i < types.Length; i++)
{
if (StreamFactory.Instance.VertexElement(types[i]).DeclarationUsage == sem.Usage)
{
if (counter == sem.UsageIndex)
{
return(i);
}
counter++;
}
}
throw new System.IndexOutOfRangeException("The number of streams of " + sem.ToString() + " are less then the requested number!");
}
/// <summary>
/// Returns an <see cref="IVertexStream"/> via its semantic.
/// </summary>
public IVertexStream this[Semantic sem] {
get {
return(this[format.GetIndex(sem)]);
}
}
/// <summary>
/// Returns true if a stream with the given semantic is contained by this <see cref="VertexFormat"/>.
/// </summary>
/// <param name="sem"><see cref="Semantic"/> to test for.</param>
/// <returns>True if a stream with the given semantic is contained by this <see cref="VertexFormat"/>.</returns>
public bool Contains(Semantic sem)
{
return(Count(sem.Usage) > sem.UsageIndex);
}
