minigpu_view library

Zero-copy Flutter rendering for minigpu / miniav GPU resources.

Provides a MiniavGpuPreview widget that displays a PreviewSource without any CPU readback on every frame.

TWO WAYS IN, and the difference is who owns the destination texture.

You already have a texture — present it directly. No copies:

final controller = MinigpuPreviewController();
final shared = gpu.createSharedOutputTexture(W, H);
// ... write to `shared` via minigpu pipeline ...
await controller.present(shared.asPreviewSource());

MiniavGpuPreview(controller: controller)   // in your widget tree

You have frames in whatever shape a producer gave you — use a GpuPane, which owns the destination and takes any of them:

final pane = GpuPane(gpu);
await pane.showSharedHandle(handle, width: w, height: h);  // capture/decode
await pane.showBuffer(buffer, width: w, height: h);        // compute output
await pane.showBytes(rgba, width: w, height: h);           // host memory

MiniavGpuPreview(controller: pane.controller)

A pane costs one GPU-to-GPU blit per displayed frame and buys two things: it accepts every source shape without the caller writing a display path per producer, and — because the caller drives GpuPane.flush — it makes the pane's update rate something you control rather than something the producer decides. Host-memory frames are uploaded and composited on the GPU, never decoded into an image on the UI isolate.

Classes

BufferGpuFrame

A frame already resident in a minigpu Buffer as packed RGBA8 — one u32 per pixel, row major. The cheapest case: no import, no upload, a GPU-to-GPU blit.

CpuBytesGpuFrame

Packed RGBA8 bytes in host memory — a CPU capture fallback, a software decoder, a generator.

GpuFrame

Something that can become the contents of a pane.

GpuPane

One displayable pane: a destination texture, the controller that shows it, and a pooled upload buffer for host-memory frames.

GpuPaneTarget

The destination a frame copies itself into, plus scratch it may borrow.

MiniavGpuPreview

Renders the current GPU frame from a MinigpuPreviewController.

MinigpuPreviewController

Listenable controller backing a MiniavGpuPreview widget.

PlanarCpuGpuFrame

Planar or subsampled bytes in host memory — NV12, I420, YUY2, BGRA.

PlanarPlane

One plane of a host-memory frame.

PreviewSource

A presentable frame source. Lifetime is owned by the producer; the preview controller borrows the underlying GPU resource until the next PreviewController.present call or until disposal.

RawGpuBufferPreviewSource

Web/storage-buffer flavour of RawSharedTexturePreviewSource: a WGPUBuffer integer handle of packed RGBA8.

RawSharedTexturePreviewSource

A present source built from RAW HANDLES, for producers that publish their surface as integers rather than as a SharedOutputTexture.

SharedHandleGpuFrame

A frame behind a platform shared handle: a D3D11 shared NT handle on Windows, as produced by screen/camera capture and by GPU video decoders.

Enums

PlanarColorRange

Whether luma/chroma use the studio-swing subset or the full 0..255 range.

PlanarFormat

Host-memory layouts this can unpack.

PreviewSourceKind

Discriminator for PreviewSource subtypes — used by the platform plugin to dispatch to the correct host-side handler.

Extensions

MiniavBufferPreviewSourceAdapter on MiniAVBuffer

Adapts a GPU-backed MiniAVBuffer into a PreviewSource.

MiniavGpuFrameAdapter on MiniAVBuffer

MinigpuPreviewSourceAdapter on SharedOutputTexture

Adapts a minigpu SharedOutputTexture into a PreviewSource.

PlanarFormatCode on PlanarFormat

Constants

kPlanarCfgWords → const int

Number of cfg words the kernel reads.

kPlanarToRgbaWgsl → const String

The conversion kernel.

Exceptions / Errors

PreviewPresentException

Thrown when the platform plugin reports an error wiring the GPU resource into Flutter's texture registry (e.g. handle is invalid, device was lost, format mismatch).

UnsupportedPreviewException

Thrown when the current platform cannot present a given source.