Use initializer methods for Vulkan structs.

[IAmNotHanni]

@yeetari already demonstrated:

template <>
VkApplicationInfo make_info() {
    VkApplicationInfo ret{};
    ret.sType = VK_STRUCTURE_TYPE_APPLICATION_INFO;
    return ret;
}

So we can fill out the missing fields:

auto app_info = make_info<VkApplicationInfo>();
app_info.pApplicationName = application_name.c_str();
app_info.applicationVersion = application_version;
app_info.pEngineName = engine_name.c_str();
app_info.engineVersion = engine_version;
app_info.apiVersion = vulkan_api_version;

We should use this for every Vulkan struct.

---

Sascha Willems example repository uses this as well:

/** @brief Initialize a buffer memory barrier with no image transfer ownership */
inline VkBufferMemoryBarrier bufferMemoryBarrier()
{
    VkBufferMemoryBarrier bufferMemoryBarrier {};
    bufferMemoryBarrier.sType = VK_STRUCTURE_TYPE_BUFFER_MEMORY_BARRIER;
    bufferMemoryBarrier.srcQueueFamilyIndex = VK_QUEUE_FAMILY_IGNORED;
    bufferMemoryBarrier.dstQueueFamilyIndex = VK_QUEUE_FAMILY_IGNORED;
    return bufferMemoryBarrier;
}

Which is used like this:

VkBufferMemoryBarrier bufferBarrier = vks::initializers::bufferMemoryBarrier();
bufferBarrier.srcAccessMask = VK_ACCESS_VERTEX_ATTRIBUTE_READ_BIT;
bufferBarrier.dstAccessMask = VK_ACCESS_SHADER_WRITE_BIT;
bufferBarrier.srcQueueFamilyIndex = vulkanDevice->queueFamilyIndices.graphics;
bufferBarrier.dstQueueFamilyIndex = vulkanDevice->queueFamilyIndices.compute;
bufferBarrier.size = VK_WHOLE_SIZE;

[IAmNotHanni]

Btw reading through Sascha Willem's code: Should we inline our code as well ?

[IAmNotHanni]

Would it be possible to change the templates so they take the values of the structures as arguments?

So instead of

auto descriptor_set_ai = wrapper::make_info<VkDescriptorSetAllocateInfo>();
descriptor_set_ai.descriptorPool = m_descriptor_pool;
descriptor_set_ai.descriptorSetCount = static_cast<std::uint32_t>(swapchain_image_count);
descriptor_set_ai.pSetLayouts = descriptor_set_layouts.data();

we would use

auto descriptor_set_ai = wrapper::make_info<VkDescriptorSetAllocateInfo>(m_descriptor_pool,
    static_cast<std::uint32_t>(swapchain_image_count),
    descriptor_set_layouts.data());

This would have the advantage that we can't ignore or forget an argument in the structure because we have to specify it directly when calling make_info. So mistakes like this can't happen:

auto descriptor_set_ai = wrapper::make_info<VkDescriptorSetAllocateInfo>();
// descriptor_set_ai.descriptorPool = m_descriptor_pool; Oops we forgot to specify this value!
descriptor_set_ai.descriptorSetCount = static_cast<std::uint32_t>(swapchain_image_count);
descriptor_set_ai.pSetLayouts = descriptor_set_layouts.data();

[IAmNotHanni]

I will close this issue because we are using this in the codebase already together with designated initializers. See pull request 487 for example.