libretro: Vulkan renderer support

src/duckstation-libretro/libretro_vulkan_host_display.h

@@ -0,0 +1,42 @@
+#pragma once
+#include "common/vulkan/texture.h"
+#include "frontend-common/vulkan_host_display.h"
+#include "libretro.h"
+
+#define HAVE_VULKAN
+#include "libretro_vulkan.h"
+
+class LibretroVulkanHostDisplay final : public FrontendCommon::VulkanHostDisplay
+{
+public:
+  LibretroVulkanHostDisplay();
+  ~LibretroVulkanHostDisplay();
+
+  static bool RequestHardwareRendererContext(retro_hw_render_callback* cb);
+
+  bool CreateRenderDevice(const WindowInfo& wi, std::string_view adapter_name, bool debug_device) override;
+  void DestroyRenderDevice() override;
+
+  void ResizeRenderWindow(s32 new_window_width, s32 new_window_height) override;
+
+  void SetVSync(bool enabled) override;
+
+  bool Render() override;
+
+protected:
+  bool CreateResources() override;
+  void DestroyResources() override;
+  VkRenderPass GetRenderPassForDisplay() const override;
+
+private:
+  static constexpr VkFormat FRAMEBUFFER_FORMAT = VK_FORMAT_R8G8B8A8_UNORM;
+
+  bool CheckFramebufferSize(u32 width, u32 height);
+
+  const retro_hw_render_interface_vulkan* m_ri = nullptr;
+
+  Vulkan::Texture m_frame_texture;
+  retro_vulkan_image m_frame_view = {};
+  VkFramebuffer m_frame_framebuffer = VK_NULL_HANDLE;
+  VkRenderPass m_frame_render_pass = VK_NULL_HANDLE;
+};