Explicit swapchain interface in `gfx`. (#1726)

* Explicit swapchain interface in `gfx`.

* Correctly return nullptr when `IRenderer` creation failed.

* Fix crashes on CUDA tests.

* Cleanups.

1 files changed, 70 insertions, 0 deletions

diff --git a/tools/gfx/vulkan/vk-descriptor-allocator.cpp b/tools/gfx/vulkan/vk-descriptor-allocator.cpp
new file mode 100644
index 000000000..c01e37642
--- /dev/null
+++ b/tools/gfx/vulkan/vk-descriptor-allocator.cpp
@@ -0,0 +1,70 @@
+#include "vk-descriptor-allocator.h"
+#include "vk-util.h"
+
+namespace gfx
+{
+VkDescriptorPool DescriptorSetAllocator::newPool()
+{
+    VkDescriptorPoolCreateInfo descriptorPoolInfo = {VK_STRUCTURE_TYPE_DESCRIPTOR_POOL_CREATE_INFO};
+    VkDescriptorPoolSize poolSizes[] = {
+        VkDescriptorPoolSize{VK_DESCRIPTOR_TYPE_SAMPLER, 1024},
+        VkDescriptorPoolSize{VK_DESCRIPTOR_TYPE_COMBINED_IMAGE_SAMPLER, 1024},
+        VkDescriptorPoolSize{VK_DESCRIPTOR_TYPE_SAMPLED_IMAGE, 4096},
+        VkDescriptorPoolSize{VK_DESCRIPTOR_TYPE_STORAGE_IMAGE, 1024},
+        VkDescriptorPoolSize{VK_DESCRIPTOR_TYPE_UNIFORM_TEXEL_BUFFER, 256},
+        VkDescriptorPoolSize{VK_DESCRIPTOR_TYPE_STORAGE_TEXEL_BUFFER, 256},
+        VkDescriptorPoolSize{VK_DESCRIPTOR_TYPE_UNIFORM_BUFFER, 4096},
+        VkDescriptorPoolSize{VK_DESCRIPTOR_TYPE_STORAGE_BUFFER, 4096},
+        VkDescriptorPoolSize{VK_DESCRIPTOR_TYPE_UNIFORM_BUFFER_DYNAMIC, 4096},
+        VkDescriptorPoolSize{VK_DESCRIPTOR_TYPE_STORAGE_BUFFER_DYNAMIC, 4096},
+        VkDescriptorPoolSize{VK_DESCRIPTOR_TYPE_INPUT_ATTACHMENT, 16},
+        VkDescriptorPoolSize{VK_DESCRIPTOR_TYPE_INLINE_UNIFORM_BLOCK_EXT, 16},
+        VkDescriptorPoolSize{VK_DESCRIPTOR_TYPE_ACCELERATION_STRUCTURE_KHR, 256}};
+    descriptorPoolInfo.maxSets = 4096;
+    descriptorPoolInfo.poolSizeCount = sizeof(poolSizes) / sizeof(VkDescriptorPoolSize);
+    descriptorPoolInfo.pPoolSizes = poolSizes;
+    descriptorPoolInfo.flags = VK_DESCRIPTOR_POOL_CREATE_FREE_DESCRIPTOR_SET_BIT;
+
+    VkDescriptorPool descriptorPool = VK_NULL_HANDLE;
+    SLANG_VK_CHECK(m_api->vkCreateDescriptorPool(
+        m_api->m_device, &descriptorPoolInfo, nullptr, &descriptorPool));
+    pools.add(descriptorPool);
+    return descriptorPool;
+}
+
+VulkanDescriptorSet DescriptorSetAllocator::allocate(VkDescriptorSetLayout layout)
+{
+    VulkanDescriptorSet rs = {};
+    VkDescriptorSetAllocateInfo allocInfo = {};
+    allocInfo.sType = VK_STRUCTURE_TYPE_DESCRIPTOR_SET_ALLOCATE_INFO;
+    allocInfo.descriptorPool = getPool();
+    allocInfo.descriptorSetCount = 1;
+    allocInfo.pSetLayouts = &layout;
+    if (m_api->vkAllocateDescriptorSets(m_api->m_device, &allocInfo, &rs.handle) == VK_SUCCESS)
+    {
+        rs.pool = allocInfo.descriptorPool;
+        return rs;
+    }
+    // If allocation from last pool fails, try all existing pools.
+    for (Slang::Index i = 0; i < pools.getCount() - 1; i++)
+    {
+        allocInfo.descriptorPool = pools[i];
+        if (m_api->vkAllocateDescriptorSets(m_api->m_device, &allocInfo, &rs.handle) == VK_SUCCESS)
+        {
+            rs.pool = allocInfo.descriptorPool;
+            return rs;
+        }
+    }
+    // If we still cannot allocate the descriptor set, add a new pool.
+    auto pool = newPool();
+    allocInfo.descriptorPool = pool;
+    if (m_api->vkAllocateDescriptorSets(m_api->m_device, &allocInfo, &rs.handle) == VK_SUCCESS)
+    {
+        rs.pool = allocInfo.descriptorPool;
+        return rs;
+    }
+    // Failed to allocate from a new pool, we are in trouble.
+    assert(!"descriptor set allocation failed.");
+    return rs;
+}
+}