/// <summary>
/// Creates a dynamic mesh based of the description.
/// This type of mesh can be modified later.
/// </summary>
/// <param name="description"></param>
/// <param name="usage"></param>
/// <returns></returns>
public DynamicMesh CreateDynamicMesh <T>(IMeshDescription <T> description, DynamicMeshUsage usage) where T : struct, IVertexType
{
if (description == null)
{
throw new ArgumentNullException(nameof(description));
}
return(CreateDynamicMesh(description.PrimitiveType, description.Vertices, usage));
}
public DynamicMesh CreateDynamicMesh(IMeshDescription description, DynamicMeshUsage usage)
{
if (description == null)
{
throw new ArgumentNullException(nameof(description));
}
return(CreateDynamicMesh(description.PrimitiveType, description.Vertices, usage));
}
public DynamicMesh CreateDynamicMesh <T>(PrimitiveType type, T[] vertices, DynamicMeshUsage usage)
where T : struct, IVertexType
{
if (vertices == null)
{
throw new ArgumentNullException();
}
if (vertices.Length == 0)
{
throw new ArgumentException();
}
var vertexType = typeof(T);
var decl = vertices[0].VertexDeclaration;
var mesh = CreateDynamicMesh(type, vertexType, decl, usage);
mesh.Update(vertices);
return(mesh);
}
/// <summary>
/// Creates a dynamic mesh based on the provided raw vertices.
/// This type of mesh can be modified later.
/// </summary>
/// <typeparam name="T"></typeparam>
/// <param name="type"></param>
/// <param name="vertices"></param>
/// <param name="usage"></param>
/// <returns></returns>
public DynamicMesh CreateDynamicMesh <T>(PrimitiveType type, List <T> vertices, DynamicMeshUsage usage)
where T : struct, IVertexType
{
if (vertices == null)
{
throw new ArgumentNullException();
}
if (vertices.Count == 0)
{
throw new ArgumentException("For dynamic meshes at least one vertex must be provided to get the vertex decleration type to use.");
}
var vertexType = typeof(T);
var decl = vertices[0].VertexDeclaration;
var mesh = CreateDynamicMesh(type, vertexType, decl, usage);
mesh.Update(vertices.ToArray());
return(mesh);
}
/// <summary>
/// Creates an empty dynamic mesh of the given type that allows data to be added to it later.
/// This type of mesh can be modified later.
/// </summary>
/// <param name="type"></param>
/// <param name="vertexType"></param>
/// <param name="declaration"></param>
/// <param name="usage"></param>
/// <returns></returns>
public DynamicMesh CreateDynamicMesh(PrimitiveType type, Type vertexType, VertexDeclaration declaration, DynamicMeshUsage usage)
{
// according to shawnhar (http://xboxforums.create.msdn.com/forums/t/5136.aspx)
//
// ''For persistent geometry (data that is drawn many times without changing), DrawPrimitives with a vertex buffer is dramatically faster.
// For dynamic geometry(which is created on the fly each time it is drawn), you should use DrawUserPrimitives, however.
// This is able to do the copy in a more efficient way than if you manually created a vertex buffer, SetData into it, and then drew from that.''
//
// However for DynamicMeshUsage.UpdateOften we use our appendingmesh which uses circlular buffer/appends the data to the buffer, it is even faster than DrawUserPrimitives
switch (usage)
{
case DynamicMeshUsage.UpdateOften:
return(new CircularBufferMesh(_device, vertexType, declaration, type));
case DynamicMeshUsage.UpdateSeldom:
return(new UpdatableDynamicMesh(_device, type));
default:
throw new ArgumentOutOfRangeException(nameof(usage), usage, null);
}
}
