pke: HACK: avoid modifying in-use vulkan buffers

Replace me with a memory barrier helper fn.

1 files changed, 44 insertions, 0 deletions

diff --git a/src/window.cpp b/src/window.cpp
index fa28e34..0c7f281 100644
--- a/src/window.cpp
+++ b/src/window.cpp
@@ -74,6 +74,13 @@ VkExtent2D Extent;
 VkSampler global_sampler;
 VkSampleCountFlagBits global_sample_count;
 
+struct pkvk_queued_actions {
+	struct pkvk_queued_actions_delete {
+		pk_arr_t<VkBuffer> buffers{};
+		pk_arr_t<VkDeviceMemory> memory{};
+	} destroy;
+} pkvk_actn_queue;
+
 // pkvk_shared.descr_set_layout.single_sampler
 // 	the pke default, works for:
 // 	2025-01-28 - present
@@ -705,6 +712,14 @@ void pkvk_texture_upload(pkvk_texture_upload_data *data, pkvk_texture_upload_dat
 	PKVK_EndBuffer(tmpBufferDetails);
 }
 
+void pkvk_queue_vk_buffer_destroy(VkBuffer buffer) {
+	pk_arr_append_t(&pkvk_actn_queue.destroy.buffers, buffer);
+}
+
+void pkvk_queue_vk_memory_free(VkDeviceMemory memory) {
+	pk_arr_append_t(&pkvk_actn_queue.destroy.memory, memory);
+}
+
 unsigned int FindQueueFamilyIndex(VkPhysicalDevice device, char hasPresentSupport = -1, VkQueueFlagBits includeBits = (VkQueueFlagBits)0U, VkQueueFlagBits excludeBits = (VkQueueFlagBits)0U) {
 
 	if (hasPresentSupport == -1 && includeBits == 0 && excludeBits == 0) {
@@ -3845,6 +3860,8 @@ void DestroyWindow() {
 		fprintf(stderr, "VkAllocator has '%u' outstanding allocations!", vulkanAllocs.next);
 	}
 	pk_arr_reset(&vulkanAllocs);
+	pk_arr_reset(&pkvk_actn_queue.destroy.buffers);
+	pk_arr_reset(&pkvk_actn_queue.destroy.memory);
 	// TODO there's un-freed vulkan stuff in the bucket
 	// comment this out to see it in the debug printout
 	pk_mem_bucket_destroy(MemBkt_Vulkan);
@@ -3909,6 +3926,33 @@ void CalculateCombinedMemReqs(uint64_t memReqsCount, VkMemoryRequirements *memRe
 	}
 }
 
+/* 2025-08-07 - JCB DEBT
+ * This function was a result of buffer synchronization issues.
+ * Specifically, the UI module was trying to reallocate its instance buffer.
+ * Vulkan was emitting an error that the buffer was in use by a command buffer.
+ * Processing these actions after the graphics queue is idle solved that specific issue.
+ * This is a stop-gap measure so I can keep working and is not intended to be permanent.
+ * PERF
+ * This will block the main thread until all in-flight renders are no longer using any of the resources needed to render a scene.
+ * Move this to a fire-and-forget background thread that uses a memory barrier and a semaphore specifically for the target resource.
+ */
+void window_tick_late(double delta) {
+	(void)delta;
+	uint32_t i;
+	if (pkvk_actn_queue.destroy.buffers.next > 0
+			|| pkvk_actn_queue.destroy.memory.next > 0) {
+		vkQueueWaitIdle(pkvk_shared.queue.graphics);
+	}
+	for (i = 0; i < pkvk_actn_queue.destroy.buffers.next; ++i) {
+		vkDestroyBuffer(vkDevice, pkvk_actn_queue.destroy.buffers[i], vkAllocator);
+	}
+	for (i = 0; i < pkvk_actn_queue.destroy.memory.next; ++i) {
+		vkFreeMemory(vkDevice, pkvk_actn_queue.destroy.memory[i], vkAllocator);
+	}
+	pk_arr_clear(&pkvk_actn_queue.destroy.buffers);
+	pk_arr_clear(&pkvk_actn_queue.destroy.memory);
+}
+
 void Render() {
 	vkWaitForFences(vkDevice, 1, &pkvk_present.fences_in_flight[CURRENT_FRAME], VK_TRUE, UINT64_MAX);