/// <summary>
/// Function to create a vertex buffer and its binding.
/// </summary>
/// <typeparam name="T">The type of data representing a vertex, must be an unmanaged value type.</typeparam>
/// <param name="graphics">The graphics interface that will create the buffer.</param>
/// <param name="vertexCount">The total number vertices that the buffer can hold.</param>
/// <param name="usage">[Optional] The intended usage for the buffer.</param>
/// <param name="binding">[Optional] The binding options for the buffer.</param>
/// <param name="initialData">[Optional] An initial set of vertex data to send to the buffer.</param>
/// <param name="bindingIndex">[Optional] The index, in vertices, inside the buffer where binding is to begin.</param>
/// <param name="bufferName">[Optional] A name for the buffer.</param>
/// <returns>A new <see cref="GorgonVertexBufferBinding"/>.</returns>
/// <exception cref="ArgumentNullException">Thrown when the <paramref name="graphics"/> parameter is <b>null</b>.</exception>
/// <remarks>
/// <para>
/// Use this to quickly create a vertex buffer and its binding based on a known vertex data type.
/// </para>
/// <para>
/// Be aware that the <see cref="VertexBuffer"/> created by this method must be disposed manually after it is no longer of any use.
/// </para>
/// </remarks>
/// <seealso cref="GorgonVertexBuffer"/>
public static GorgonVertexBufferBinding CreateVertexBuffer <T>(GorgonGraphics graphics,
int vertexCount,
ResourceUsage usage = ResourceUsage.Default,
VertexIndexBufferBinding binding = VertexIndexBufferBinding.None,
GorgonNativeBuffer <T> initialData = null,
int bindingIndex = 0,
string bufferName = null)
where T : unmanaged
{
if (graphics == null)
{
throw new ArgumentNullException(nameof(graphics));
}
int vertexSize = Unsafe.SizeOf <T>();
var buffer = new GorgonVertexBuffer(graphics,
new GorgonVertexBufferInfo(bufferName)
{
SizeInBytes = vertexCount * vertexSize,
Binding = binding,
Usage = usage
},
initialData?.Cast <byte>());
return(new GorgonVertexBufferBinding(buffer, vertexSize, bindingIndex * vertexSize));
}
/// <summary>
/// Function to validate the bindings for a given buffer.
/// </summary>
/// <param name="usage">The usage flags for the buffer.</param>
/// <param name="binding">The bindings to apply to the buffer, pass <b>null</b> to skip usage and binding check.</param>
internal static void ValidateBufferBindings(ResourceUsage usage, VertexIndexBufferBinding binding)
{
switch (usage)
{
case ResourceUsage.Dynamic:
case ResourceUsage.Immutable:
if ((binding & VertexIndexBufferBinding.StreamOut) == VertexIndexBufferBinding.StreamOut)
{
throw new GorgonException(GorgonResult.CannotCreate, string.Format(Resources.GORGFX_ERR_BUFFER_NO_SO, usage));
}
if ((binding & VertexIndexBufferBinding.UnorderedAccess) == VertexIndexBufferBinding.UnorderedAccess)
{
throw new GorgonException(GorgonResult.CannotCreate, string.Format(Resources.GORGFX_ERR_BUFFER_NO_UAV, usage));
}
break;
case ResourceUsage.Staging:
if (binding != VertexIndexBufferBinding.None)
{
throw new GorgonException(GorgonResult.CannotCreate, string.Format(Resources.GORGFX_ERR_BUFFER_STAGING_CANNOT_BE_BOUND_TO_GPU, binding));
}
break;
}
}
