"Vertex buffers: Staging buffer"

TODO: "Vertex buffers: Index buffer"
https://vulkan-tutorial.com/Vertex_buffers/Index_buffer

src/main.rs

@@ -1609,84 +1609,61 @@ impl VulkanApp {
     }
 
     fn create_vertex_buffer(&mut self) -> Result<(), String> {
-        let mut buffer_info: ffi::VkBufferCreateInfo = unsafe { std::mem::zeroed() };
+        let buffer_size: ffi::VkDeviceSize =
+            (std::mem::size_of::<Vertex>() * VERTICES.len()) as u64;
 
-        buffer_info.sType = ffi::VkStructureType_VK_STRUCTURE_TYPE_BUFFER_CREATE_INFO;
-        buffer_info.size = (std::mem::size_of::<Vertex>() * VERTICES.len()) as u64;
-        buffer_info.usage = ffi::VkBufferUsageFlagBits_VK_BUFFER_USAGE_VERTEX_BUFFER_BIT;
-        buffer_info.sharingMode = ffi::VkSharingMode_VK_SHARING_MODE_EXCLUSIVE;
-
-        let result = unsafe {
-            ffi::vkCreateBuffer(
-                self.device,
-                std::ptr::addr_of!(buffer_info),
-                std::ptr::null(),
-                std::ptr::addr_of_mut!(self.vertex_buffer),
-            )
-        };
-        if result != ffi::VkResult_VK_SUCCESS {
-            return Err(String::from("Failed to create vertex buffer!"));
-        }
-
-        let mut mem_reqs: ffi::VkMemoryRequirements = unsafe { std::mem::zeroed() };
-        unsafe {
-            ffi::vkGetBufferMemoryRequirements(
-                self.device,
-                self.vertex_buffer,
-                std::ptr::addr_of_mut!(mem_reqs),
-            );
-        }
-
-        let mut alloc_info: ffi::VkMemoryAllocateInfo = unsafe { std::mem::zeroed() };
-        alloc_info.sType = ffi::VkStructureType_VK_STRUCTURE_TYPE_MEMORY_ALLOCATE_INFO;
-        alloc_info.allocationSize = mem_reqs.size;
-        alloc_info.memoryTypeIndex = self.find_memory_type(
-            mem_reqs.memoryTypeBits,
+        let (staging_buffer, staging_buffer_mem) = self.create_buffer(
+            buffer_size,
+            ffi::VkBufferUsageFlagBits_VK_BUFFER_USAGE_TRANSFER_SRC_BIT,
             ffi::VkMemoryPropertyFlagBits_VK_MEMORY_PROPERTY_HOST_VISIBLE_BIT
                 | ffi::VkMemoryPropertyFlagBits_VK_MEMORY_PROPERTY_HOST_COHERENT_BIT,
         )?;
 
-        let result = unsafe {
-            ffi::vkAllocateMemory(
-                self.device,
-                std::ptr::addr_of!(alloc_info),
-                std::ptr::null(),
-                std::ptr::addr_of_mut!(self.vertex_buffer_memory),
-            )
+        struct CleanupStaging {
+            device: ffi::VkDevice,
+            staging_buf: ffi::VkBuffer,
+            staging_buf_mem: ffi::VkDeviceMemory,
+        }
+        impl Drop for CleanupStaging {
+            fn drop(&mut self) {
+                unsafe {
+                    ffi::vkDestroyBuffer(self.device, self.staging_buf, std::ptr::null());
+                    ffi::vkFreeMemory(self.device, self.staging_buf_mem, std::ptr::null());
+                }
+            }
+        }
+        let _cleanup_staging = CleanupStaging {
+            device: self.device,
+            staging_buf: staging_buffer,
+            staging_buf_mem: staging_buffer_mem,
         };
-        if result != ffi::VkResult_VK_SUCCESS {
-            return Err(String::from("Failed to allocate vertex buffer memory!"));
-        }
-
-        unsafe {
-            ffi::vkBindBufferMemory(
-                self.device,
-                self.vertex_buffer,
-                self.vertex_buffer_memory,
-                0,
-            );
-        }
 
         let mut data_ptr: *mut c_void = unsafe { std::mem::zeroed() };
         unsafe {
             ffi::vkMapMemory(
                 self.device,
-                self.vertex_buffer_memory,
+                staging_buffer_mem,
                 0,
-                buffer_info.size,
+                buffer_size,
                 0,
                 std::ptr::addr_of_mut!(data_ptr),
             );
-        }
-
-        unsafe {
             let data_ptr_vertices: *mut [Vertex; 3] = std::mem::transmute(data_ptr);
             *data_ptr_vertices = VERTICES;
+            ffi::vkUnmapMemory(self.device, staging_buffer_mem);
         }
 
-        unsafe {
-            ffi::vkUnmapMemory(self.device, self.vertex_buffer_memory);
-        }
+        let (buffer, buffer_mem) = self.create_buffer(
+            buffer_size,
+            ffi::VkBufferUsageFlagBits_VK_BUFFER_USAGE_TRANSFER_DST_BIT
+                | ffi::VkBufferUsageFlagBits_VK_BUFFER_USAGE_VERTEX_BUFFER_BIT,
+            ffi::VkMemoryPropertyFlagBits_VK_MEMORY_PROPERTY_DEVICE_LOCAL_BIT,
+        )?;
+
+        self.vertex_buffer = buffer;
+        self.vertex_buffer_memory = buffer_mem;
+
+        self.copy_buffer(staging_buffer, self.vertex_buffer, buffer_size)?;
 
         Ok(())
     }
@@ -1746,6 +1723,137 @@ impl VulkanApp {
 
         Ok((vertex_input_info, bind_desc, attr_descs))
     }
+
+    fn create_buffer(
+        &mut self,
+        size: ffi::VkDeviceSize,
+        usage: ffi::VkBufferUsageFlags,
+        properties: ffi::VkMemoryPropertyFlags,
+    ) -> Result<(ffi::VkBuffer, ffi::VkDeviceMemory), String> {
+        let mut buffer_info: ffi::VkBufferCreateInfo = unsafe { std::mem::zeroed() };
+        buffer_info.sType = ffi::VkStructureType_VK_STRUCTURE_TYPE_BUFFER_CREATE_INFO;
+        buffer_info.size = size;
+        buffer_info.usage = usage;
+        buffer_info.sharingMode = ffi::VkSharingMode_VK_SHARING_MODE_EXCLUSIVE;
+
+        let mut buffer: ffi::VkBuffer = std::ptr::null_mut();
+        let result = unsafe {
+            ffi::vkCreateBuffer(
+                self.device,
+                std::ptr::addr_of!(buffer_info),
+                std::ptr::null(),
+                std::ptr::addr_of_mut!(buffer),
+            )
+        };
+        if result != ffi::VkResult_VK_SUCCESS {
+            return Err(String::from("Failed to create buffer!"));
+        }
+
+        let mut mem_req: ffi::VkMemoryRequirements = unsafe { std::mem::zeroed() };
+        unsafe {
+            ffi::vkGetBufferMemoryRequirements(
+                self.device,
+                buffer,
+                std::ptr::addr_of_mut!(mem_req),
+            );
+        }
+
+        let mut alloc_info: ffi::VkMemoryAllocateInfo = unsafe { std::mem::zeroed() };
+        alloc_info.sType = ffi::VkStructureType_VK_STRUCTURE_TYPE_MEMORY_ALLOCATE_INFO;
+        alloc_info.allocationSize = mem_req.size;
+        alloc_info.memoryTypeIndex = self.find_memory_type(mem_req.memoryTypeBits, properties)?;
+
+        let mut buffer_mem: ffi::VkDeviceMemory = std::ptr::null_mut();
+
+        let result = unsafe {
+            ffi::vkAllocateMemory(
+                self.device,
+                std::ptr::addr_of!(alloc_info),
+                std::ptr::null(),
+                std::ptr::addr_of_mut!(buffer_mem),
+            )
+        };
+        if result != ffi::VkResult_VK_SUCCESS {
+            return Err(String::from("Failed to allocate buffer memory"));
+        }
+
+        unsafe {
+            ffi::vkBindBufferMemory(self.device, buffer, buffer_mem, 0);
+        }
+
+        Ok((buffer, buffer_mem))
+    }
+
+    fn copy_buffer(
+        &mut self,
+        src_buffer: ffi::VkBuffer,
+        dst_buffer: ffi::VkBuffer,
+        size: ffi::VkDeviceSize,
+    ) -> Result<(), String> {
+        let mut alloc_info: ffi::VkCommandBufferAllocateInfo = unsafe { std::mem::zeroed() };
+        alloc_info.sType = ffi::VkStructureType_VK_STRUCTURE_TYPE_COMMAND_BUFFER_ALLOCATE_INFO;
+        alloc_info.level = ffi::VkCommandBufferLevel_VK_COMMAND_BUFFER_LEVEL_PRIMARY;
+        alloc_info.commandPool = self.command_pool;
+        alloc_info.commandBufferCount = 1;
+
+        let mut command_buffer: ffi::VkCommandBuffer = std::ptr::null_mut();
+
+        unsafe {
+            ffi::vkAllocateCommandBuffers(
+                self.device,
+                std::ptr::addr_of!(alloc_info),
+                std::ptr::addr_of_mut!(command_buffer),
+            );
+        }
+
+        let mut begin_info: ffi::VkCommandBufferBeginInfo = unsafe { std::mem::zeroed() };
+        begin_info.sType = ffi::VkStructureType_VK_STRUCTURE_TYPE_COMMAND_BUFFER_BEGIN_INFO;
+        begin_info.flags =
+            ffi::VkCommandBufferUsageFlagBits_VK_COMMAND_BUFFER_USAGE_ONE_TIME_SUBMIT_BIT;
+
+        unsafe {
+            ffi::vkBeginCommandBuffer(command_buffer, std::ptr::addr_of!(begin_info));
+        }
+
+        let mut copy_region: ffi::VkBufferCopy = unsafe { std::mem::zeroed() };
+        copy_region.srcOffset = 0;
+        copy_region.dstOffset = 0;
+        copy_region.size = size;
+
+        unsafe {
+            ffi::vkCmdCopyBuffer(
+                command_buffer,
+                src_buffer,
+                dst_buffer,
+                1,
+                std::ptr::addr_of!(copy_region),
+            );
+            ffi::vkEndCommandBuffer(command_buffer);
+        }
+
+        let mut submit_info: ffi::VkSubmitInfo = unsafe { std::mem::zeroed() };
+        submit_info.sType = ffi::VkStructureType_VK_STRUCTURE_TYPE_SUBMIT_INFO;
+        submit_info.commandBufferCount = 1;
+        submit_info.pCommandBuffers = std::ptr::addr_of!(command_buffer);
+
+        unsafe {
+            ffi::vkQueueSubmit(
+                self.graphics_queue,
+                1,
+                std::ptr::addr_of!(submit_info),
+                std::ptr::null_mut(),
+            );
+            ffi::vkQueueWaitIdle(self.graphics_queue);
+            ffi::vkFreeCommandBuffers(
+                self.device,
+                self.command_pool,
+                1,
+                std::ptr::addr_of!(command_buffer),
+            );
+        }
+
+        Ok(())
+    }
 }
 
 impl Drop for VulkanApp {