use staging buffer

Author: Piasy

README.md

@@ -2,5 +2,5 @@
 
 Step by step tutorial of Vulkan on Android, follow https://vulkan-tutorial.com.
 
-+ We need [`vulkan_wrappe`](https://developer.android.com/ndk/guides/graphics/getting-started.html#using) on Android, which could be [download from GitHub](https://github.com/LunarG/VulkanSamples/tree/master/common).
++ We need [`vulkan_wrapper`](https://developer.android.com/ndk/guides/graphics/getting-started.html#using) on Android, which could be [download from GitHub](https://github.com/LunarG/VulkanSamples/tree/master/common).
 + In Android Studio, just put shader code under `src/main/shaders` folder, they will be compiled into `.spv` files, and packaged as assets.

app/src/main/cpp/vulkan_triangle.cpp

@@ -27,9 +27,9 @@ const std::vector<const char *> deviceExtensions = {
 };
 
 const std::vector<Vertex> vertices = {
-        {{0.0f, -0.5f}, {1.0f, 1.0f, 1.0f}},
-        {{0.5f, 0.5f}, {0.0f, 1.0f, 0.0f}},
-        {{-0.5f, 0.5f}, {0.0f, 0.0f, 1.0f}}
+        {{0.0f,  -0.5f}, {1.0f, 1.0f, 1.0f}},
+        {{0.5f,  0.5f},  {0.0f, 1.0f, 0.0f}},
+        {{-0.5f, 0.5f},  {0.0f, 0.0f, 1.0f}}
 };
 
 #ifdef NDEBUG
@@ -666,37 +666,97 @@ void HelloTriangleApplication::createFramebuffers() {
     }
 }
 
-void HelloTriangleApplication::createVertexBuffer() {
+void HelloTriangleApplication::createBuffer(VkDeviceSize size, VkBufferUsageFlags usage,
+                                            VkMemoryPropertyFlags properties, VkBuffer &buffer,
+                                            VkDeviceMemory &bufferMemory) {
     VkBufferCreateInfo bufferInfo = {
             .sType = VK_STRUCTURE_TYPE_BUFFER_CREATE_INFO,
-            .size = sizeof(vertices[0]) * vertices.size(),
-            .usage = VK_BUFFER_USAGE_VERTEX_BUFFER_BIT,
+            .size = size,
+            .usage = usage,
             .sharingMode = VK_SHARING_MODE_EXCLUSIVE,
     };
-
-    if (vkCreateBuffer(device, &bufferInfo, nullptr, &vertexBuffer) != VK_SUCCESS) {
-        throw std::runtime_error("failed to create vertex buffer!");
+    if (vkCreateBuffer(device, &bufferInfo, nullptr, &buffer) != VK_SUCCESS) {
+        throw std::runtime_error("failed to create buffer!");
     }
 
     VkMemoryRequirements memRequirements;
-    vkGetBufferMemoryRequirements(device, vertexBuffer, &memRequirements);
+    vkGetBufferMemoryRequirements(device, buffer, &memRequirements);
 
     VkMemoryAllocateInfo allocInfo = {
             .sType = VK_STRUCTURE_TYPE_MEMORY_ALLOCATE_INFO,
             .allocationSize = memRequirements.size,
-            .memoryTypeIndex = findMemoryType(memRequirements.memoryTypeBits,
-                                              VK_MEMORY_PROPERTY_HOST_VISIBLE_BIT
-                                              | VK_MEMORY_PROPERTY_HOST_COHERENT_BIT),
+            .memoryTypeIndex = findMemoryType(memRequirements.memoryTypeBits, properties),
     };
-    if (vkAllocateMemory(device, &allocInfo, nullptr, &vertexBufferMemory) != VK_SUCCESS) {
-        throw std::runtime_error("failed to allocate vertex buffer memory!");
+
+    if (vkAllocateMemory(device, &allocInfo, nullptr, &bufferMemory) != VK_SUCCESS) {
+        throw std::runtime_error("failed to allocate buffer memory!");
     }
-    vkBindBufferMemory(device, vertexBuffer, vertexBufferMemory, 0);
 
-    void* data;
-    vkMapMemory(device, vertexBufferMemory, 0, bufferInfo.size, 0, &data);
-    memcpy(data, vertices.data(), (size_t) bufferInfo.size);
-    vkUnmapMemory(device, vertexBufferMemory);
+    vkBindBufferMemory(device, buffer, bufferMemory, 0);
+}
+
+void HelloTriangleApplication::createVertexBuffer() {
+    VkDeviceSize bufferSize = sizeof(vertices[0]) * vertices.size();
+
+    VkBuffer stagingBuffer;
+    VkDeviceMemory stagingBufferMemory;
+    createBuffer(bufferSize,
+                 VK_BUFFER_USAGE_TRANSFER_SRC_BIT,
+                 VK_MEMORY_PROPERTY_HOST_VISIBLE_BIT | VK_MEMORY_PROPERTY_HOST_COHERENT_BIT,
+                 stagingBuffer,
+                 stagingBufferMemory);
+
+    void *data;
+    vkMapMemory(device, stagingBufferMemory, 0, bufferSize, 0, &data);
+    memcpy(data, vertices.data(), (size_t) bufferSize);
+    vkUnmapMemory(device, stagingBufferMemory);
+
+    createBuffer(bufferSize,
+                 VK_BUFFER_USAGE_TRANSFER_DST_BIT | VK_BUFFER_USAGE_VERTEX_BUFFER_BIT,
+                 VK_MEMORY_PROPERTY_DEVICE_LOCAL_BIT,
+                 vertexBuffer,
+                 vertexBufferMemory);
+
+    copyBuffer(stagingBuffer, vertexBuffer, bufferSize);
+
+    vkDestroyBuffer(device, stagingBuffer, nullptr);
+    vkFreeMemory(device, stagingBufferMemory, nullptr);
+}
+
+void HelloTriangleApplication::copyBuffer(
+        VkBuffer srcBuffer, VkBuffer dstBuffer, VkDeviceSize size) {
+    VkCommandBufferAllocateInfo allocInfo = {
+            .sType = VK_STRUCTURE_TYPE_COMMAND_BUFFER_ALLOCATE_INFO,
+            .level = VK_COMMAND_BUFFER_LEVEL_PRIMARY,
+            .commandPool = commandPool,
+            .commandBufferCount = 1,
+    };
+
+    VkCommandBuffer commandBuffer;
+    vkAllocateCommandBuffers(device, &allocInfo, &commandBuffer);
+
+    VkCommandBufferBeginInfo beginInfo = {
+            .sType = VK_STRUCTURE_TYPE_COMMAND_BUFFER_BEGIN_INFO,
+            .flags = VK_COMMAND_BUFFER_USAGE_ONE_TIME_SUBMIT_BIT,
+    };
+    vkBeginCommandBuffer(commandBuffer, &beginInfo);
+
+    VkBufferCopy copyRegion = {
+            .size = size
+    };
+    vkCmdCopyBuffer(commandBuffer, srcBuffer, dstBuffer, 1, &copyRegion);
+
+    vkEndCommandBuffer(commandBuffer);
+
+    VkSubmitInfo submitInfo = {
+            .sType = VK_STRUCTURE_TYPE_SUBMIT_INFO,
+            .commandBufferCount = 1,
+            .pCommandBuffers = &commandBuffer,
+    };
+    vkQueueSubmit(graphicsQueue, 1, &submitInfo, VK_NULL_HANDLE);
+    vkQueueWaitIdle(graphicsQueue);
+
+    vkFreeCommandBuffers(device, commandPool, 1, &commandBuffer);
 }
 
 uint32_t HelloTriangleApplication::findMemoryType(

app/src/main/cpp/vulkan_triangle.h

@@ -125,10 +125,15 @@ class HelloTriangleApplication {
 
     void createFramebuffers();
 
+    void createBuffer(VkDeviceSize size, VkBufferUsageFlags usage, VkMemoryPropertyFlags properties,
+                      VkBuffer &buffer, VkDeviceMemory &bufferMemory);
+
     void createCommandPool();
 
     void createVertexBuffer();
 
+    void copyBuffer(VkBuffer srcBuffer, VkBuffer dstBuffer, VkDeviceSize size);
+
     uint32_t findMemoryType(uint32_t typeFilter, VkMemoryPropertyFlags properties);
 
     void createCommandBuffers();