Struct ViewportRenderer 

pub struct ViewportRenderer { /* private fields */ }

High-level renderer wrapping all GPU resources and providing framework-agnostic prepare() and paint() methods.

Implementations

impl ViewportRenderer

pub fn new(device: &Device, target_format: TextureFormat) -> Self

Create a new renderer with default settings (no MSAA). Call once at application startup.

pub fn with_sample_count( device: &Device, target_format: TextureFormat, sample_count: u32, ) -> Self

Create a new renderer with the specified MSAA sample count (1, 2, or 4).

When using MSAA (sample_count > 1), the caller must create multisampled color and depth textures and use them as render pass attachments with the final surface texture as the resolve target.

pub fn resources(&self) -> &ViewportGpuResources

Access the underlying GPU resources (e.g. for mesh uploads).

pub fn last_frame_stats(&self) -> FrameStats

Performance counters from the last completed frame.

pub fn resources_mut(&mut self) -> &mut ViewportGpuResources

Mutable access to the underlying GPU resources (e.g. for mesh uploads).

pub fn prepare(&mut self, device: &Device, queue: &Queue, frame: &FrameData)

Upload per-frame data to GPU buffers and render the shadow pass. Call before paint().

pub fn paint(&self, render_pass: &mut RenderPass<'static>, frame: &FrameData)

Issue draw calls for the viewport. Call inside a wgpu::RenderPass.

This method requires a 'static render pass (as provided by egui’s CallbackTrait). For non-static render passes (iced, manual wgpu), use paint_to.

pub fn paint_to<'rp>( &'rp self, render_pass: &mut RenderPass<'rp>, frame: &FrameData, )

Issue draw calls into a render pass with any lifetime.

Identical to paint but accepts a render pass with a non-'static lifetime, making it usable from iced, raw wgpu, or any framework that creates its own render pass.

pub fn render( &mut self, device: &Device, queue: &Queue, output_view: &TextureView, frame: &FrameData, ) -> CommandBuffer

High-level HDR render method. Handles the full post-processing pipeline: scene → HDR texture → (bloom) → (SSAO) → tone map → output_view.

When frame.post_process.enabled is false, falls back to a simple LDR render pass targeting output_view directly.

Returns a CommandBuffer ready to submit.

pub fn render_offscreen( &mut self, device: &Device, queue: &Queue, frame: &FrameData, width: u32, height: u32, ) -> Vec<u8>

Render a frame to an offscreen texture and return raw RGBA bytes.

Creates a temporary wgpu::Texture render target of the given dimensions, runs all render passes (shadow, scene, post-processing) into it via render(), then copies the result back to CPU memory.

No OS window or wgpu::Surface is required. The caller is responsible for initialising the wgpu adapter with compatible_surface: None and for constructing a valid FrameData (including viewport_size matching width/height).

Returns width * height * 4 bytes in RGBA8 layout. The caller encodes to PNG/EXR independently — no image codec dependency in this crate.

pub fn pick_scene_gpu( &mut self, device: &Device, queue: &Queue, cursor: Vec2, frame: &FrameData, ) -> Option<GpuPickHit>

GPU object-ID pick: renders the scene to an offscreen R32Uint texture and reads back the single pixel under cursor.

This is O(1) in mesh complexity — every object is rendered with a flat u32 ID, and only one pixel is read back. For triangle-level queries (barycentric scalar probe, exact world position), use the CPU crate::interaction::picking::pick_scene path instead.

The pipeline is lazily initialized on first call — zero overhead when this method is never invoked.

Arguments

• device — wgpu device
• queue — wgpu queue
• cursor — cursor position in viewport-local pixels (top-left origin)
• frame — current frame data (camera, scene_items, viewport_size)

Returns

Some(GpuPickHit) if an object is under the cursor, None if empty space.