protected SwapChain(ref Descriptor desc, Device device, string label) : base(ref desc, device, label)
{
Assert.Debug(desc.MaxFramesInFlight > 0, "Invalid in-flight framecount!");
Assert.Debug(desc.BufferCount > 0, "Invalid backbuffer count!");
Assert.Debug(desc.AssociatedGraphicsQueue != null, "No graphics queue passed!");
Assert.Debug(desc.AssociatedGraphicsQueue.Desc.Type == CommandListType.Graphics, "Passed command queue needs to be a graphics queue!");
var fenceDesc = new Fence.Descriptor {
InitialValue = 0
};
FrameFence = device.Create(ref fenceDesc);
FrameFence.AddRef();
Create();
BackbufferResources = new Resource[desc.BufferCount];
var resourceDesc = new Resource.Descriptor
{
Type = Resource.Descriptor.Types.Backbuffer,
DataDimension = Dimension.Texture2D
};
for (uint i = 0; i < BackbufferResources.Length; ++i)
{
BackbufferResources[i] = device.Create(ref resourceDesc, "Backbuffer");
BackbufferResources[i].CreateFromSwapChain(this, i);
}
}
/// <summary>
/// Waits until all prepared frames are renderd and the GPU has no more tasks.
/// Use this method carefully since it will usually come with a huge stall!
/// </summary>
public void WaitUntilAllFramesCompleted()
{
if (NumCompletedFramesGPU != NumCompletedFramesCPU)
{
FrameFence.WaitForCompletion(NumCompletedFramesCPU, TimeSpan.MaxValue);
}
}
/// <summary>
/// Swaps backbuffer. If syncInterval is bigger than zero, this function must wait until the GPU is able to perform the swap. (TODO: Is that correct?)
/// </summary>
/// <remarks>
/// Signals the internal frameFence that is used to determine how many frames are inflight.
/// Does not call any additional wait function (like WaitForFreeInflightFrame).
/// </remarks>
/// <param name="syncInterval">Synchronize presentation after the nth vertical blank. 0 means no synchronization.</param>
public void EndFrame(uint syncInterval = 1)
{
// Present and mark end of frame with fence signal.
Present(syncInterval);
++NumCompletedFramesCPU;
FrameFence.Signal(NumCompletedFramesCPU);
activeInFlightFrameIndex = (activeInFlightFrameIndex + 1) % Desc.MaxFramesInFlight;
}
/// <summary>
/// Waits until only Desc.MaxFramesInFlight-1 frames are inflight and will then trigger the OnBeginRendering event.
/// If an application is highly GPU bound, it will wait for the GPU to complete the rendering for this swapChain in this function.
/// </summary>
public void BeginFrame()
{
// Fullfill the MaxFramesInFlight constraint.
Assert.Debug(NumFramesInFlight <= Desc.MaxFramesInFlight, "It should be impossible to have more than Desc.MaxFramesInFlight frames in flight.");
if (NumFramesInFlight == Desc.MaxFramesInFlight)
{
FrameFence.WaitForCompletion(NumCompletedFramesGPU + 1, TimeSpan.MaxValue);
}
// Anounce frame start to all listeners.
OnBeginFrame?.Invoke(activeInFlightFrameIndex);
}
internal override void Destroy()
{
WaitUntilAllFramesCompleted();
FrameFence.RemoveRef();
FrameFence.Destroy();
foreach (var resource in BackbufferResources)
{
resource.RemoveRef();
resource.Dispose();
}
BackbufferResources = null;
base.Destroy();
}
