Struct DissolveTransitionNode 

pub struct DissolveTransitionNode {
    pub mask: Vec<u8>,
    pub to_rgba: Vec<u8>,
    pub to_width: u32,
    pub to_height: u32,
}

Per-pixel dissolve: clip B shows through wherever the supplied mask is set.

This is FFmpeg’s xfade=transition=dissolve. Unlike FadeTransitionNode every output pixel is fully clip A or fully clip B, never a mixture of them — the node selects, it does not blend.

It takes no progress of its own: which pixels have turned over is entirely the mask’s decision, and ff_filter::dissolve_mask is what turns a progress into one.

Like its siblings this node renders to an Rgba8Unorm target (the shared build_pipeline hard-codes that format), so it does not run in an Rgba16Float graph.

Fields

mask: Vec<u8>

Per-pixel selection as an RGBA mask: 255 shows clip B, 0 shows clip A.

Supplied rather than computed. FFmpeg’s dissolve keys off fract(sinf(x*12.9898 + y*78.233) * 43758.545), whose argument reaches ~110 000 at 1080p – past where f32 holds it steadily, so the value is not reproducible across implementations and a WGSL copy would reveal a different set of pixels than the CPU reference. ff_filter::dissolve_mask builds this once and both paths read it (#1732).

to_rgba: Vec<u8>

Clip B as RGBA bytes (to_width × to_height × 4).

to_width: u32

Width of to_rgba.

to_height: u32

Height of to_rgba.

Implementations

impl DissolveTransitionNode

pub fn new( mask: Vec<u8>, to_rgba: Vec<u8>, to_width: u32, to_height: u32, ) -> Self

Creates a dissolve from clip A (the node input) to clip B (to_rgba), revealing B wherever mask is set. Build mask with ff_filter::dissolve_mask.

Trait Implementations

impl RenderNode for DissolveTransitionNode

Available on crate feature wgpu only.

fn input_count(&self) -> usize

Number of input textures required by this node (default: 1).

fn process( &self, inputs: &[&Texture], outputs: &[&Texture], ctx: &RenderContext, )

Run the GPU render pass.

fn pass_count(&self) -> usize

Number of render passes (default: 1). Multi-pass nodes (e.g. gaussian blur) return 2 or more.

fn output_dimensions(&self, in_w: u32, in_h: u32) -> (u32, u32)

Output dimensions this node produces given its input dimensions.

fn set_param(&self, _param: NodeParam) -> bool

Applies param to this node in place, returning whether it was taken.

impl RenderNodeCpu for DissolveTransitionNode

fn process_cpu(&self, rgba: &mut [u8], _w: u32, _h: u32)

Process rgba in-place.