Made it possible to specify the desired queue priorities.

If none are provided, it will use 1.0f for everything.

src/VkBootstrap.cpp

@@ -560,11 +560,11 @@ PhysicalDeviceSelector::Suitable PhysicalDeviceSelector::is_device_suitable (VkP
 
 	VkPhysicalDeviceProperties device_properties;
 	vkGetPhysicalDeviceProperties (phys_device, &device_properties);
-	if ((criteria.preferred_type == PreferredDevice::discrete &&
+	if ((criteria.preferred_type == PreferredDeviceType::discrete &&
 	        device_properties.deviceType != VK_PHYSICAL_DEVICE_TYPE_DISCRETE_GPU) ||
-	    (criteria.preferred_type == PreferredDevice::integrated &&
+	    (criteria.preferred_type == PreferredDeviceType::integrated &&
 	        device_properties.deviceType != VK_PHYSICAL_DEVICE_TYPE_INTEGRATED_GPU) ||
-	    (criteria.preferred_type == PreferredDevice::virtual_gpu &&
+	    (criteria.preferred_type == PreferredDeviceType::virtual_gpu &&
 	        device_properties.deviceType != VK_PHYSICAL_DEVICE_TYPE_VIRTUAL_GPU)) {
 		if (criteria.allow_fallback)
 			suitable = Suitable::partial;
@@ -598,8 +598,14 @@ detail::Expected<PhysicalDevice, VkResult> PhysicalDeviceSelector::select () {
 	if (!physical_devices.has_value ()) {
 		return detail::Error{ physical_devices.error ().error_code, "Failed to find physical devices" };
 	}
+	if (physical_devices.value ().size () == 0) {
+		return detail::Error{ VK_ERROR_INITIALIZATION_FAILED, "No physical devices found" };
+	}
 
 	PhysicalDevice physical_device;
+	if (criteria.use_first_gpu_unconditionally) {
+		physical_device.phys_device = physical_devices.value ().at (0);
+	} else {
 		for (const auto& device : physical_devices.value ()) {
 			auto suitable = is_device_suitable (device);
 			if (suitable == Suitable::yes) {
@@ -609,6 +615,7 @@ detail::Expected<PhysicalDevice, VkResult> PhysicalDeviceSelector::select () {
 				physical_device.phys_device = device;
 			}
 		}
+	}
 
 	if (physical_device.phys_device == VK_NULL_HANDLE) {
 		return detail::Error{ VK_ERROR_INITIALIZATION_FAILED, "Failed to find a suitable GPU!" };
@@ -638,19 +645,11 @@ PhysicalDeviceSelector& PhysicalDeviceSelector::set_surface (VkSurfaceKHR surfac
 	info.headless = false;
 	return *this;
 }
-PhysicalDeviceSelector& PhysicalDeviceSelector::prefer_discrete () {
+PhysicalDeviceSelector& PhysicalDeviceSelector::prefer_gpu_device_type (PreferredDeviceType type) {
-	criteria.preferred_type = PreferredDevice::discrete;
+	criteria.preferred_type = type;
 	return *this;
 }
-PhysicalDeviceSelector& PhysicalDeviceSelector::prefer_integrated () {
+PhysicalDeviceSelector& PhysicalDeviceSelector::allow_fallback_gpu (bool fallback) {
-	criteria.preferred_type = PreferredDevice::integrated;
-	return *this;
-}
-PhysicalDeviceSelector& PhysicalDeviceSelector::prefer_virtual_gpu () {
-	criteria.preferred_type = PreferredDevice::virtual_gpu;
-	return *this;
-}
-PhysicalDeviceSelector& PhysicalDeviceSelector::allow_fallback (bool fallback) {
 	criteria.allow_fallback = fallback;
 	return *this;
 }
@@ -678,10 +677,20 @@ PhysicalDeviceSelector& PhysicalDeviceSelector::add_required_extension (std::str
 	criteria.required_extensions.push_back (extension);
 	return *this;
 }
+PhysicalDeviceSelector& PhysicalDeviceSelector::add_required_extensions (std::vector<std::string> extensions) {
+	criteria.required_extensions.insert (
+	    criteria.required_extensions.end (), extensions.begin (), extensions.end ());
+	return *this;
+}
 PhysicalDeviceSelector& PhysicalDeviceSelector::add_desired_extension (std::string extension) {
 	criteria.desired_extensions.push_back (extension);
 	return *this;
 }
+PhysicalDeviceSelector& PhysicalDeviceSelector::add_desired_extensions (std::vector<std::string> extensions) {
+	criteria.desired_extensions.insert (
+	    criteria.desired_extensions.end (), extensions.begin (), extensions.end ());
+	return *this;
+}
 PhysicalDeviceSelector& PhysicalDeviceSelector::set_minimum_version (uint32_t major, uint32_t minor) {
 	criteria.required_version = VK_MAKE_VERSION (major, minor, 0);
 	return *this;
@@ -694,6 +703,14 @@ PhysicalDeviceSelector& PhysicalDeviceSelector::set_required_features (VkPhysica
 	criteria.required_features = features;
 	return *this;
 }
+PhysicalDeviceSelector& PhysicalDeviceSelector::set_desired_features (VkPhysicalDeviceFeatures features) {
+	criteria.desired_features = features;
+	return *this;
+}
+PhysicalDeviceSelector& PhysicalDeviceSelector::select_first_device_unconditionally (bool unconditionally) {
+	criteria.use_first_gpu_unconditionally = unconditionally;
+	return *this;
+}
 
 // ---- Device ---- //
 
@@ -711,16 +728,33 @@ DeviceBuilder::DeviceBuilder (PhysicalDevice phys_device) {
 detail::Expected<Device, VkResult> DeviceBuilder::build () {
 	auto& queue_properties = info.physical_device.queue_family_properties;
 	std::vector<QueueFamily> families;
-	families.push_back ({ queue_properties.graphics, std::vector<float> (queue_properties.count_graphics) });
+
-	if (queue_properties.compute != -1 && queue_properties.compute != queue_properties.graphics)
+	families.push_back ({ queue_properties.graphics,
-		families.push_back ({ queue_properties.compute, std::vector<float> (queue_properties.count_compute) });
+	    info.graphics_queue_priorities.size () == 0 ?
+	        std::vector<float> (info.use_multiple_queues_per_family ? queue_properties.count_graphics : 1, 1.0f) :
+	        info.graphics_queue_priorities });
+
+	if (queue_properties.compute != -1 && queue_properties.compute != queue_properties.graphics) {
+		families.push_back ({ queue_properties.compute,
+		    info.compute_queue_priorities.size () == 0 ?
+		        std::vector<float> (info.use_multiple_queues_per_family ? queue_properties.count_compute : 1, 1.0f) :
+		        info.compute_queue_priorities });
+	}
+
 	if (queue_properties.transfer != -1 && queue_properties.transfer != queue_properties.graphics &&
 	    queue_properties.transfer != queue_properties.compute)
-		families.push_back ({ queue_properties.transfer, std::vector<float> (queue_properties.count_transfer) });
+		families.push_back ({ queue_properties.transfer,
+		    info.transfer_queue_priorities.size () == 0 ?
+		        std::vector<float> (info.use_multiple_queues_per_family ? queue_properties.count_transfer : 1, 1.0f) :
+		        info.transfer_queue_priorities });
+
 	if (queue_properties.sparse != -1 && queue_properties.sparse != queue_properties.graphics &&
 	    queue_properties.sparse != queue_properties.compute &&
 	    queue_properties.sparse != queue_properties.transfer)
-		families.push_back ({ queue_properties.sparse, std::vector<float> (queue_properties.count_sparse) });
+		families.push_back ({ queue_properties.sparse,
+		    info.sparse_queue_priorities.size () == 0 ?
+		        std::vector<float> (info.use_multiple_queues_per_family ? queue_properties.count_sparse : 1, 1.0f) :
+		        info.sparse_queue_priorities });
 
 	std::vector<VkDeviceQueueCreateInfo> queueCreateInfos;
 	for (auto& queue : families) {
@@ -763,6 +797,31 @@ template <typename T> DeviceBuilder& DeviceBuilder::add_pNext (T* structure) {
 	info.pNext_chain.push_back (reinterpret_cast<VkBaseOutStructure*> (structure));
 	return *this;
 }
+DeviceBuilder& DeviceBuilder::use_multiple_queues_per_family (bool multi_queue) {
+	info.use_multiple_queues_per_family = true;
+	return *this;
+}
+DeviceBuilder& DeviceBuilder::set_graphics_queue_priorities (std::vector<float> priorities) {
+	if (info.physical_device.queue_family_properties.count_graphics >= priorities.size ())
+		info.graphics_queue_priorities = priorities;
+	return *this;
+}
+DeviceBuilder& DeviceBuilder::set_compute_queue_priorities (std::vector<float> priorities) {
+	if (info.physical_device.queue_family_properties.count_compute >= priorities.size ())
+		info.compute_queue_priorities = priorities;
+	return *this;
+}
+DeviceBuilder& DeviceBuilder::set_transfer_queue_priorities (std::vector<float> priorities) {
+	if (info.physical_device.queue_family_properties.count_transfer >= priorities.size ())
+		info.transfer_queue_priorities = priorities;
+	return *this;
+}
+DeviceBuilder& DeviceBuilder::set_sparse_queue_priorities (std::vector<float> priorities) {
+	if (info.physical_device.queue_family_properties.count_sparse >= priorities.size ())
+		info.sparse_queue_priorities = priorities;
+	return *this;
+}
+
 
 // ---- Queue ---- //
 

src/VkBootstrap.h

@@ -236,11 +236,9 @@ struct PhysicalDeviceSelector {
 
 	PhysicalDeviceSelector& set_surface (VkSurfaceKHR instance);
 
-	PhysicalDeviceSelector& prefer_discrete ();
+	enum PreferredDeviceType { discrete, integrated, virtual_gpu, cpu, dont_care };
-	PhysicalDeviceSelector& prefer_integrated ();
+	PhysicalDeviceSelector& prefer_gpu_device_type (PreferredDeviceType type = PreferredDeviceType::discrete);
-	PhysicalDeviceSelector& prefer_virtual_gpu ();
+	PhysicalDeviceSelector& allow_fallback_gpu (bool fallback = true);
-
-	PhysicalDeviceSelector& allow_fallback (bool fallback = true);
 
 	PhysicalDeviceSelector& require_present (bool require = true);
 	PhysicalDeviceSelector& require_dedicated_transfer_queue ();
@@ -250,12 +248,18 @@ struct PhysicalDeviceSelector {
 	PhysicalDeviceSelector& desired_device_memory_size (VkDeviceSize size);
 
 	PhysicalDeviceSelector& add_required_extension (std::string extension);
+	PhysicalDeviceSelector& add_required_extensions (std::vector<std::string> extensions);
+
 	PhysicalDeviceSelector& add_desired_extension (std::string extension);
+	PhysicalDeviceSelector& add_desired_extensions (std::vector<std::string> extensions);
 
 	PhysicalDeviceSelector& set_desired_version (uint32_t major, uint32_t minor);
 	PhysicalDeviceSelector& set_minimum_version (uint32_t major = 1, uint32_t minor = 0);
 
 	PhysicalDeviceSelector& set_required_features (VkPhysicalDeviceFeatures features);
+	PhysicalDeviceSelector& set_desired_features (VkPhysicalDeviceFeatures features);
+
+	PhysicalDeviceSelector& select_first_device_unconditionally (bool unconditionally = true);
 
 	private:
 	struct PhysicalDeviceInfo {
@@ -264,10 +268,8 @@ struct PhysicalDeviceSelector {
 		bool headless = false;
 	} info;
 
-	enum PreferredDevice { discrete, integrated, virtual_gpu, cpu, dont_care };
-
 	struct SelectionCriteria {
-		PreferredDevice preferred_type = PreferredDevice::discrete;
+		PreferredDeviceType preferred_type = PreferredDeviceType::discrete;
 		bool allow_fallback = true;
 		bool require_present = true;
 		bool require_dedicated_transfer_queue = false;
@@ -284,6 +286,7 @@ struct PhysicalDeviceSelector {
 		VkPhysicalDeviceFeatures required_features{};
 		VkPhysicalDeviceFeatures desired_features{};
 
+		bool use_first_gpu_unconditionally = false;
 	} criteria;
 
 	enum class Suitable { yes, partial, no };
@@ -308,12 +311,27 @@ class DeviceBuilder {
 
 	template <typename T> DeviceBuilder& add_pNext (T* structure);
 
+	DeviceBuilder& use_multiple_queues_per_family (bool multi_queue = true);
+
+	DeviceBuilder& set_graphics_queue_priorities (std::vector<float> priorities);
+	DeviceBuilder& set_compute_queue_priorities (std::vector<float> priorities);
+	DeviceBuilder& set_transfer_queue_priorities (std::vector<float> priorities);
+	DeviceBuilder& set_sparse_queue_priorities (std::vector<float> priorities);
+
+
 	private:
 	struct DeviceInfo {
 		VkDeviceCreateFlags flags;
 		std::vector<VkBaseOutStructure*> pNext_chain;
 		PhysicalDevice physical_device;
 		std::vector<std::string> extensions;
+
+		bool use_multiple_queues_per_family = false;
+		std::vector<float> graphics_queue_priorities;
+		std::vector<float> compute_queue_priorities;
+		std::vector<float> transfer_queue_priorities;
+		std::vector<float> sparse_queue_priorities;
+
 	} info;
 };