private void Update(object sender, EventArgs e)
{
swapChain.BeginFrame();
commandList.StartRecording();
commandList.PerformResourceTransition(CommandList.BarrierType.Immediate, swapChain.ActiveBackBuffer, ResourceUsage.ReadWriteUsage.Present, ResourceUsage.ReadWriteUsage.RenderTargetColor);
commandList.SetRenderTargets(descHeapRenderTargets, swapChain.ActiveSwapChainBufferIndex, null, 0);
commandList.ClearRenderTargetView(CommandList.ClearTarget.Color, new Vector4(1.0f, 0.0f, 1.0f, 1.0f));
commandList.PerformResourceTransition(CommandList.BarrierType.Immediate, swapChain.ActiveBackBuffer, ResourceUsage.ReadWriteUsage.RenderTargetColor, ResourceUsage.ReadWriteUsage.Present);
commandList.EndRecording();
commandQueue.ExecuteCommandList(commandList);
swapChain.EndFrame();
}