dc-terrain / src / dc_vulkan_ext.h

#ifndef DC_VULKAN_EXT_H
#define DC_VULKAN_EXT_H

// Vulkan extension loader for CLAS (VK_NV_cluster_acceleration_structure)
// and mesh shaders (VK_NV_mesh_shader).
//
// Loads VkDevice and extension function pointers from Godot's RenderingDevice
// via get_driver_resource() + dlsym(libvulkan.so).
//
// This is separate from Godot's rendering pipeline — we create our own
// command pool for acceleration structure operations.

#include <cstdint>
#include <vulkan/vulkan.h>

struct DCVulkanContext {
	VkInstance instance = VK_NULL_HANDLE;
	VkPhysicalDevice physical_device = VK_NULL_HANDLE;
	VkDevice device = VK_NULL_HANDLE;
	VkQueue queue = VK_NULL_HANDLE;
	uint32_t queue_family = 0;
	VkCommandPool command_pool = VK_NULL_HANDLE;

	// CLAS function pointers (VK_NV_cluster_acceleration_structure)
	PFN_vkGetClusterAccelerationStructureBuildSizesNV
		GetClusterAccelerationStructureBuildSizesNV = nullptr;
	PFN_vkCmdBuildClusterAccelerationStructureIndirectNV
		CmdBuildClusterAccelerationStructureIndirectNV = nullptr;

	// KHR RT function pointers (VK_KHR_acceleration_structure)
	PFN_vkCreateAccelerationStructureKHR CreateAccelerationStructureKHR = nullptr;
	PFN_vkDestroyAccelerationStructureKHR DestroyAccelerationStructureKHR = nullptr;
	PFN_vkGetAccelerationStructureDeviceAddressKHR GetAccelerationStructureDeviceAddressKHR = nullptr;
	PFN_vkGetAccelerationStructureBuildSizesKHR GetAccelerationStructureBuildSizesKHR = nullptr;
	PFN_vkCmdBuildAccelerationStructuresKHR CmdBuildAccelerationStructuresKHR = nullptr;

	bool rt_supported = false;

	// Core function pointers (loaded via dlsym)
	PFN_vkAllocateCommandBuffers AllocateCommandBuffers = nullptr;
	PFN_vkFreeCommandBuffers FreeCommandBuffers = nullptr;
	PFN_vkBeginCommandBuffer BeginCommandBuffer = nullptr;
	PFN_vkEndCommandBuffer EndCommandBuffer = nullptr;
	PFN_vkQueueSubmit QueueSubmit = nullptr;
	PFN_vkQueueWaitIdle QueueWaitIdle = nullptr;
	PFN_vkCreateCommandPool CreateCommandPool = nullptr;
	PFN_vkDestroyCommandPool DestroyCommandPool = nullptr;
	PFN_vkCreateBuffer CreateBuffer = nullptr;
	PFN_vkDestroyBuffer DestroyBuffer = nullptr;
	PFN_vkAllocateMemory AllocateMemory = nullptr;
	PFN_vkFreeMemory FreeMemory = nullptr;
	PFN_vkBindBufferMemory BindBufferMemory = nullptr;
	PFN_vkGetBufferMemoryRequirements GetBufferMemoryRequirements = nullptr;
	PFN_vkGetBufferDeviceAddress GetBufferDeviceAddress = nullptr;
	PFN_vkGetPhysicalDeviceMemoryProperties GetPhysicalDeviceMemoryProperties = nullptr;
	PFN_vkCmdPipelineBarrier CmdPipelineBarrier = nullptr;
	PFN_vkMapMemory MapMemory = nullptr;
	PFN_vkUnmapMemory UnmapMemory = nullptr;
	PFN_vkDeviceWaitIdle DeviceWaitIdle = nullptr;

	bool clas_supported = false;

	// Initialize from Godot's RenderingDevice.
	// Must be called from the main thread (before workers start).
	bool initialize();

	// Clean up command pool and any allocated resources.
	void cleanup();

	// Check if CLAS extension is available and loaded.
	bool has_clas() const { return clas_supported; }
	bool has_rt() const { return rt_supported; }
};

#endif // DC_VULKAN_EXT_H