Merge pull request 'feat(vulkan-rt): Mesh::BuildProcedural — AABB (procedural) BLAS build path (#33)' (#35) from claude/issue-33 into master

interfaces/Crafter.Graphics-Mesh.cppm

@@ -31,12 +31,27 @@ import Crafter.Asset;
 import :VulkanBuffer;
 
 export namespace Crafter {
+    // One procedural primitive's axis-aligned bounding box, in object
+    // space. Layout-compatible with VkAabbPositionsKHR (24-byte stride),
+    // so a span of these uploads directly as a
+    // VK_GEOMETRY_TYPE_AABBS_KHR build input. Mirrors the DOM-side
+    // definition below so portable user code compiles unchanged.
+    struct RTAabb {
+        float min[3];
+        float max[3];
+    };
+    static_assert(sizeof(RTAabb) == sizeof(VkAabbPositionsKHR));
+
     class Mesh {
         public:
         VulkanBuffer<char, false> scratchBuffer;
         VulkanBuffer<char, false> blasBuffer;
         VulkanBuffer<Vector<float, 3, 3>, true> vertexBuffer;
         VulkanBuffer<std::uint32_t, true> indexBuffer;
+        // AABB build input for the procedural path (BuildProcedural).
+        // Lifetime contract matches vertexBuffer/indexBuffer: must stay
+        // alive until the build submitted on `cmd` completes.
+        VulkanBuffer<RTAabb, true> aabbBuffer;
         // Lives until the cmd buffer issued by the compressed Build path
         // completes execution. Kept as a member so the recorded
         // vkCmdDecompressMemoryEXT references valid memory until the queue
@@ -57,6 +72,18 @@ export namespace Crafter {
         // Region 2 (data) is not consumed here — the caller decompresses it
         // into their own buffer if needed (or uses Compression::DecompressCPU).
         void Build(const ::Crafter::CompressedMeshAsset& asset, VkCommandBuffer cmd);
+        // Build an AABB (procedural) BLAS from a list of object-space
+        // boxes (VK_GEOMETRY_TYPE_AABBS_KHR). The hit group bound to
+        // instances of this mesh must be a
+        // VK_RAY_TRACING_SHADER_GROUP_TYPE_PROCEDURAL_HIT_GROUP_KHR group
+        // carrying an intersection shader; that shader is invoked for
+        // each box the ray enters and reports the surface hit via
+        // reportIntersectionEXT. `opaque` maps to
+        // VK_GEOMETRY_OPAQUE_BIT_KHR: pass false (the WebGPU-path
+        // default) to let any-hit shaders run. Same scratch/lifetime
+        // handling as the triangle Build; instances reference blasAddr
+        // exactly like a triangle BLAS.
+        void BuildProcedural(std::span<const RTAabb> aabbs, bool opaque, VkCommandBuffer cmd);
     };
 }
 #endif // !CRAFTER_GRAPHICS_WINDOW_DOM