From 7a86595a1b7b558e4742bc7911932b5271c14118 Mon Sep 17 00:00:00 2001
From: Wunkolo <Wunkolo@gmail.com>
Date: Sun, 20 Aug 2023 23:35:52 -0700
Subject: [PATCH] Add vulkan sampler cache

---
 CMakeLists.txt                            |  2 ++
 include/renderer_vk/vk_sampler_cache.hpp  | 28 ++++++++++++++++++++
 src/core/renderer_vk/vk_sampler_cache.cpp | 31 +++++++++++++++++++++++
 3 files changed, 61 insertions(+)
 create mode 100644 include/renderer_vk/vk_sampler_cache.hpp
 create mode 100644 src/core/renderer_vk/vk_sampler_cache.cpp

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 1218b97b..b953175e 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -242,6 +242,7 @@ if(ENABLE_VULKAN)
 		include/renderer_vk/vk_api.hpp include/renderer_vk/vk_debug.hpp
 		include/renderer_vk/vk_descriptor_heap.hpp
 		include/renderer_vk/vk_descriptor_update_batch.hpp
+		include/renderer_vk/vk_sampler_cache.hpp
 		include/renderer_vk/vk_memory.hpp include/renderer_vk/vk_pica.hpp
 	)
 
@@ -249,6 +250,7 @@ if(ENABLE_VULKAN)
 		src/core/renderer_vk/vk_api.cpp src/core/renderer_vk/vk_debug.cpp
 		src/core/renderer_vk/vk_descriptor_heap.cpp
 		src/core/renderer_vk/vk_descriptor_update_batch.cpp
+		src/core/renderer_vk/vk_sampler_cache.cpp
 		src/core/renderer_vk/vk_memory.cpp src/core/renderer_vk/vk_pica.cpp
 	)
 
diff --git a/include/renderer_vk/vk_sampler_cache.hpp b/include/renderer_vk/vk_sampler_cache.hpp
new file mode 100644
index 00000000..8cb27689
--- /dev/null
+++ b/include/renderer_vk/vk_sampler_cache.hpp
@@ -0,0 +1,28 @@
+#pragma once
+
+#include <optional>
+#include <unordered_map>
+
+#include "helpers.hpp"
+#include "vk_api.hpp"
+
+namespace Vulkan {
+	// Implements a simple pool of reusable sampler objects
+	class SamplerCache {
+	  private:
+		const vk::Device device;
+
+		std::unordered_map<std::size_t, vk::UniqueSampler> samplerMap;
+
+		explicit SamplerCache(vk::Device device);
+
+	  public:
+		~SamplerCache() = default;
+
+		SamplerCache(SamplerCache&&) = default;
+
+		const vk::Sampler& getSampler(const vk::SamplerCreateInfo& samplerInfo);
+
+		static std::optional<SamplerCache> create(vk::Device device);
+	};
+}  // namespace Vulkan
\ No newline at end of file
diff --git a/src/core/renderer_vk/vk_sampler_cache.cpp b/src/core/renderer_vk/vk_sampler_cache.cpp
new file mode 100644
index 00000000..884264b1
--- /dev/null
+++ b/src/core/renderer_vk/vk_sampler_cache.cpp
@@ -0,0 +1,31 @@
+#include "renderer_vk/vk_sampler_cache.hpp"
+
+#include <vulkan/vulkan_hash.hpp>
+
+#include "helpers.hpp"
+
+namespace Vulkan {
+
+	SamplerCache::SamplerCache(vk::Device device) : device(device) {}
+
+	const vk::Sampler& SamplerCache::getSampler(const vk::SamplerCreateInfo& samplerInfo) {
+		const std::size_t samplerHash = std::hash<vk::SamplerCreateInfo>()(samplerInfo);
+
+		// Cache hit
+		if (samplerMap.contains(samplerHash)) {
+			return samplerMap.at(samplerHash).get();
+		}
+
+		if (auto createResult = device.createSamplerUnique(samplerInfo); createResult.result == vk::Result::eSuccess) {
+			return (samplerMap[samplerHash] = std::move(createResult.value)).get();
+		} else {
+			Helpers::panic("Error creating sampler: %s\n", vk::to_string(createResult.result).c_str());
+		}
+	}
+
+	std::optional<SamplerCache> SamplerCache::create(vk::Device device) {
+		SamplerCache newSamplerCache(device);
+
+		return {std::move(newSamplerCache)};
+	}
+}  // namespace Vulkan
\ No newline at end of file