Initial commit

src/graphics/host_gpu/renderer/streamBuffer.h

@@ -0,0 +1,48 @@
+#ifndef EMULATOR_SRC_GRAPHICS_HOST_GPU_RENDERER_STREAMBUFFER_H_
+#define EMULATOR_SRC_GRAPHICS_HOST_GPU_RENDERER_STREAMBUFFER_H_
+
+#include "common/abi.h"
+#include "common/common.h"
+
+#include <cstdint>
+#include <memory>
+#include <mutex>
+
+namespace Libs::Graphics {
+
+struct GraphicContext;
+struct VulkanBuffer;
+
+// Host-only mapped stream mechanism. BufferCache owns the upload policy/API; one backend remains
+// attached to each CommandBuffer so Reset is provably after that command's fence. Replacing this
+// backend with scheduler watches will not change descriptor/render call sites.
+class HostStreamBuffer final {
+public:
+	HostStreamBuffer();
+	~HostStreamBuffer();
+	KYTY_CLASS_NO_COPY(HostStreamBuffer);
+
+	[[nodiscard]] bool Copy(GraphicContext* ctx, const void* src, uint64_t size,
+	                        uint64_t alignment, VulkanBuffer** out_buffer, uint64_t* out_offset,
+	                        uint64_t* out_range);
+	void Reset() noexcept;
+	void Release() noexcept;
+
+private:
+	void EnsureBuffer(GraphicContext* ctx);
+
+	// Interim fence-scoped backend: one command processor's eight live command buffers reserve up
+	// to 128 MiB lazily. Additional active processors scale that aggregate until this backend is
+	// replaced by a single 64 MiB scheduler-watched ring; the BufferCache seam stays fixed.
+	static constexpr uint64_t CAPACITY = 16ull * 1024ull * 1024ull;
+
+	mutable std::mutex m_mutex;
+	GraphicContext*    m_ctx        = nullptr;
+	std::unique_ptr<VulkanBuffer> m_buffer;
+	void*              m_mapped     = nullptr;
+	uint64_t           m_offset     = 0;
+};
+
+} // namespace Libs::Graphics
+
+#endif // EMULATOR_SRC_GRAPHICS_HOST_GPU_RENDERER_STREAMBUFFER_H_