//! The toolkit's raw-Vulkan (ash) renderer — the workspace-wide replacement for
 //! the wgpu backend, grown in cce-designer (milestones 1–3 + cutover) and moved
 //! here for general use.
 //!
 //! `VkRenderer` owns the whole stack: instance (+ validation layers in debug
 //! builds or with `CCE_VK_VALIDATION=1`), `VK_KHR_wayland_surface`, sRGB
 //! swapchain (premultiplied alpha, FIFO), gpu-allocator memory, and three
 //! pipelines compiled from WGSL through naga at startup:
 //!
 //! - **2D** (`shader2d.wgsl`): the union of the engine and designer dialects —
 //!   quads with circle clipping, the wavy-blob sentinel, window-corner
 //!   rounding (radius 0 disables), and blur-behind plates (negative alpha)
 //!   sampling the renderer-managed backdrop.
 //! - **Text** (`glyph.wgsl` + [`TextSpan`]): cosmic-text shaping (a direct dependency since the
 //!   wgpu path retired) + swash rasterization into a self-managed glyph atlas, with
 //!   per-span bounds clipping, rotation, and circle clipping.
 //! - **3D** (`scene3d.wgsl` + [`SceneDraw`]): handle-based [`Vertex3D`] meshes
 //!   with a depth buffer, rendered into the full-size backdrop image
 //!   (scissored to a pane) and copied beneath the UI pass — the same image is
 //!   the blur-behind source.
 //!
 //! A fourth pipeline is built lazily on first use:
 //!
 //! - **RT** (`rt.wgsl` + [`RtTriangle`]/[`RtMaterial`]/[`RtCamera`]): the
 //!   tier-1 compute path tracer — CPU-built SAH BVH in storage buffers,
 //!   progressive accumulation, blitted into the backdrop's viewport-pane
 //!   region as a drop-in alternative to the raster 3D pass. Plain compute:
 //!   no `VK_KHR_ray_*` needed.
 //!
 //! And beside the pipelines, one seam that is not a pipeline:
 //!
 //! - **Compute jobs** ([`ComputeDevice`] + [`Kernel`] + [`Binding`]): upload
 //!   buffers, dispatch a WGSL compute entry point on a headless device, read
 //!   back. The RT pass's machinery with a general face, for consumers with
 //!   arrays to transform (cce-designer's solver operators).
 //!
 //! The wgpu↔Vulkan Y-flip is a negative-height viewport (like wgpu-hal), NOT
 //! naga's ADJUST_COORDINATE_SPACE — a shader-side flip would reverse winding
 //! and break the 3D pipeline's back-face culling.
 
 mod compute;
 mod core;
 pub mod image;
 mod renderer;
 mod rt;
 mod scene;
 mod text;
 
 pub use compute::{workgroups, BindKind, Binding, ComputeDevice, Kernel, MAX_BINDINGS};
 pub use core::VkCore;
 pub use image::{
     free_image, recycle_buffer, renderer_epoch, update_pixels, upload_pixels, upload_rgba, ImageQuad,
     PixelFormat,
 };
 pub use renderer::{Batch2D, Frame2D, PlatePush, VkRenderer, MAX_PLATE_FEATURES};
 pub use rt::{RtCamera, RtMaterial, RtOffscreen, RtTriangle};
 pub use scene::{MeshId, SceneDraw, Vertex3D};
 pub use text::TextSpan;
 
 /// Pay the process-wide, window-independent renderer costs up front: the
 /// shared Vulkan instance (ICD enumeration + driver init), one throwaway
 /// device (loads the driver's device-level libraries), and the naga WGSL
 /// compiles. For daemon-style processes (cce-cloud) that build a renderer per
 /// window: called at daemon startup, it moves the multi-second cold-cache hit
 /// off the first window's critical path.
 pub fn prewarm() {
     renderer::shader2d_spirv();
     renderer::glyph_spirv();
     renderer::scene3d_spirv();
     drop(VkCore::new_headless());
 }