From 7d221b1fd6194e59bc0783740a2a17ac71fa4da5 Mon Sep 17 00:00:00 2001
From: Mikko Rasa <tdb@tdb.fi>
Date: Mon, 20 Dec 2021 23:03:33 +0200
Subject: [PATCH] Reset staging buffers in TransferQueue once the transfers are
 done

---
 source/backends/vulkan/transferqueue.cpp | 11 +++++++++++
 source/backends/vulkan/transferqueue.h   |  3 +++
 2 files changed, 14 insertions(+)

diff --git a/source/backends/vulkan/transferqueue.cpp b/source/backends/vulkan/transferqueue.cpp
index 8db81020..9fc94140 100644
--- a/source/backends/vulkan/transferqueue.cpp
+++ b/source/backends/vulkan/transferqueue.cpp
@@ -28,6 +28,7 @@ void TransferQueue::allocate_staging(PendingTransfer &transfer, size_t size)
 	transfer.staging_address = static_cast<char *>(i->mapped_address)+transfer.offset;
 
 	i->used += size;
+	++i->async_count;
 }
 
 TransferQueue::PendingTransfer &TransferQueue::prepare_transfer(const void *object, bool ordered, size_t size)
@@ -53,6 +54,8 @@ void TransferQueue::finalize_transfer(void *staging)
 	if(i==async_transfers.end() || i->staging_address!=staging)
 		throw key_error(staging);
 
+	if(i->buffer_index>=0)
+		--buffers[i->buffer_index].async_count;
 	insert_transfer(move(*i));
 	async_transfers.erase(i);
 }
@@ -79,6 +82,7 @@ void TransferQueue::dispatch_transfers(VkCommandBuffer command_buffer)
 	if(transfers.empty())
 		return;
 
+	++current_frame;
 	for(auto i=transfers.begin(); i!=transfers.end(); )
 	{
 		auto j = i;
@@ -91,11 +95,18 @@ void TransferQueue::dispatch_transfers(VkCommandBuffer command_buffer)
 		{
 			VkBuffer buffer = (i->buffer_index>=0 ? buffers[i->buffer_index].buffer : 0);
 			i->transfer(command_buffer, buffer, i->offset);
+			if(i->buffer_index>=0)
+				buffers[i->buffer_index].last_frame = current_frame;
 		}
 	}
 
 	transfers.clear();
 	next_orders.clear();
+
+	unsigned n_frames_in_flight = device.get_n_frames_in_flight();
+	for(StagingBuffer &b: buffers)
+		if(!b.async_count && b.last_frame+n_frames_in_flight<current_frame)
+			b.used = 0;
 }
 
 
diff --git a/source/backends/vulkan/transferqueue.h b/source/backends/vulkan/transferqueue.h
index 592bb69e..e78137fc 100644
--- a/source/backends/vulkan/transferqueue.h
+++ b/source/backends/vulkan/transferqueue.h
@@ -22,6 +22,8 @@ private:
 		std::size_t size = 0;
 		std::size_t used = 0;
 		void *mapped_address = 0;
+		unsigned async_count = 0;
+		unsigned last_frame = 0;
 
 		StagingBuffer(Device &, std::size_t);
 		StagingBuffer(StagingBuffer &&);
@@ -46,6 +48,7 @@ private:
 	std::vector<PendingTransfer> transfers;
 	std::vector<PendingTransfer> async_transfers;
 	std::map<const void *, unsigned> next_orders;
+	unsigned current_frame = 0;
 
 public:
 	TransferQueue(Device &);
-- 
2.43.0