feature(vulkan): back transient attachments with lazily allocated memory

examples/vulkan/CarControlDemo/main.cpp

@@ -91,8 +91,9 @@ int main() {
   // Manually-managed depth image for dynamic rendering.
   core::vulkan::VulkanImage depth_image(
       &context, swap_chain->swapchain_extent.width, swap_chain->swapchain_extent.height,
-      kDepthFormat, VK_IMAGE_USAGE_DEPTH_STENCIL_ATTACHMENT_BIT, VK_IMAGE_ASPECT_DEPTH_BIT,
-      VK_MEMORY_PROPERTY_DEVICE_LOCAL_BIT, VK_IMAGE_TILING_OPTIMAL);
+      kDepthFormat,
+      VK_IMAGE_USAGE_TRANSIENT_ATTACHMENT_BIT | VK_IMAGE_USAGE_DEPTH_STENCIL_ATTACHMENT_BIT,
+      VK_IMAGE_ASPECT_DEPTH_BIT, VK_MEMORY_PROPERTY_DEVICE_LOCAL_BIT, VK_IMAGE_TILING_OPTIMAL);
   depth_image.TransitionDepthImageLayout(
       VK_IMAGE_LAYOUT_UNDEFINED, VK_IMAGE_LAYOUT_DEPTH_STENCIL_ATTACHMENT_OPTIMAL, kDepthFormat);
 

examples/vulkan/FPSShooterDemo/main.cpp

@@ -95,8 +95,9 @@ int main() {
   // Manually-managed depth image for the dynamic rendering path.
   core::vulkan::VulkanImage depth_image(
       &context, swap_chain->swapchain_extent.width, swap_chain->swapchain_extent.height,
-      kDepthFormat, VK_IMAGE_USAGE_DEPTH_STENCIL_ATTACHMENT_BIT, VK_IMAGE_ASPECT_DEPTH_BIT,
-      VK_MEMORY_PROPERTY_DEVICE_LOCAL_BIT, VK_IMAGE_TILING_OPTIMAL);
+      kDepthFormat,
+      VK_IMAGE_USAGE_TRANSIENT_ATTACHMENT_BIT | VK_IMAGE_USAGE_DEPTH_STENCIL_ATTACHMENT_BIT,
+      VK_IMAGE_ASPECT_DEPTH_BIT, VK_MEMORY_PROPERTY_DEVICE_LOCAL_BIT, VK_IMAGE_TILING_OPTIMAL);
   depth_image.TransitionDepthImageLayout(
       VK_IMAGE_LAYOUT_UNDEFINED, VK_IMAGE_LAYOUT_DEPTH_STENCIL_ATTACHMENT_OPTIMAL, kDepthFormat);
 

examples/vulkan/MultiSamplingDemo/main.cpp

@@ -60,8 +60,10 @@ int main() {
 
   core::vulkan::VulkanImage depth_image(
       &context, swap_chain->swapchain_extent.width, swap_chain->swapchain_extent.height,
-      kDepthFormat, VK_IMAGE_USAGE_DEPTH_STENCIL_ATTACHMENT_BIT, VK_IMAGE_ASPECT_DEPTH_BIT,
-      VK_MEMORY_PROPERTY_DEVICE_LOCAL_BIT, VK_IMAGE_TILING_OPTIMAL, 1, msaa_samples);
+      kDepthFormat,
+      VK_IMAGE_USAGE_TRANSIENT_ATTACHMENT_BIT | VK_IMAGE_USAGE_DEPTH_STENCIL_ATTACHMENT_BIT,
+      VK_IMAGE_ASPECT_DEPTH_BIT, VK_MEMORY_PROPERTY_DEVICE_LOCAL_BIT, VK_IMAGE_TILING_OPTIMAL, 1,
+      msaa_samples);
   depth_image.TransitionDepthImageLayout(
       VK_IMAGE_LAYOUT_UNDEFINED, VK_IMAGE_LAYOUT_DEPTH_STENCIL_ATTACHMENT_OPTIMAL, kDepthFormat);
 

examples/vulkan/PhysicsDemo/main.cpp

@@ -79,8 +79,9 @@ int main() {
   // rendering we own the depth attachment here.
   core::vulkan::VulkanImage depth_image(
       &context, swap_chain->swapchain_extent.width, swap_chain->swapchain_extent.height,
-      kDepthFormat, VK_IMAGE_USAGE_DEPTH_STENCIL_ATTACHMENT_BIT, VK_IMAGE_ASPECT_DEPTH_BIT,
-      VK_MEMORY_PROPERTY_DEVICE_LOCAL_BIT, VK_IMAGE_TILING_OPTIMAL);
+      kDepthFormat,
+      VK_IMAGE_USAGE_TRANSIENT_ATTACHMENT_BIT | VK_IMAGE_USAGE_DEPTH_STENCIL_ATTACHMENT_BIT,
+      VK_IMAGE_ASPECT_DEPTH_BIT, VK_MEMORY_PROPERTY_DEVICE_LOCAL_BIT, VK_IMAGE_TILING_OPTIMAL);
   depth_image.TransitionDepthImageLayout(
       VK_IMAGE_LAYOUT_UNDEFINED, VK_IMAGE_LAYOUT_DEPTH_STENCIL_ATTACHMENT_OPTIMAL, kDepthFormat);
 

tests/vulkan/CMakeLists.txt

@@ -48,3 +48,6 @@ target_include_directories(vulkan_gaussian_benchmark PRIVATE
   ${CMAKE_CURRENT_BINARY_DIR}/shaders)
 add_dependencies(vulkan_gaussian_benchmark vulkan_shaders)
 target_link_libraries(vulkan_gaussian_benchmark PRIVATE mat vulkan)
+
+add_executable(vulkan_transient_attachment_benchmark benchmarks/TransientAttachmentBenchmark.cpp)
+target_link_libraries(vulkan_transient_attachment_benchmark PRIVATE vulkan)

tests/vulkan/TransientAttachment.frag

@@ -0,0 +1,10 @@
+#version 450
+
+layout(push_constant) uniform Draw {
+  vec4 color;
+  float depth;
+} draw;
+
+layout(location = 0) out vec4 out_color;
+
+void main() { out_color = draw.color; }

tests/vulkan/TransientAttachment.vert

@@ -0,0 +1,11 @@
+#version 450
+
+layout(push_constant) uniform Draw {
+  vec4 color;
+  float depth;
+} draw;
+
+void main() {
+  const vec2 positions[3] = vec2[](vec2(-1.0, -1.0), vec2(3.0, -1.0), vec2(-1.0, 3.0));
+  gl_Position = vec4(positions[gl_VertexIndex], draw.depth, 1.0);
+}