Clip + spotlight on vector masks

Linear: AUT-58

Output is pixel-identical to the M-MASK.1 / M-MASK.6 equivalents — the vector path lets you drive both off the same Vector value, and adds freehand-polygon variants of each.

Closes the M-VEC.4..6 refactor zone. apply_clip (the rounded-crop foundation from M-MASK.1) and apply_spotlight (M-MASK.6) now route through the shared mask + compose path. Path-driven variants of both land here.

#![allow(unused)]
fn main() {
use glam::Vec2;
use wisp::{Color, Vector, VectorShape};

// Path-driven crop (impossible before M-VEC.6):
let diamond = Vector::new(VectorShape::path(vec![
    Vec2::new( 0.0,  0.6),
    Vec2::new( 0.6,  0.0),
    Vec2::new( 0.0, -0.6),
    Vec2::new(-0.6,  0.0),
]));
renderer.apply_clip_vector(&app, &diamond, &foreground, &output);

// Path-driven spotlight (impossible before M-VEC.6):
renderer.apply_spotlight_vector(
    &app,
    &diamond,
    Color::rgba(0.0, 0.0, 0.0, 0.7),
    &base,
    &output,
);
}

Architecture

• apply_clip (and the new apply_clip_vector) — uses cached_vector_mask_texture + apply_mask_to_texture. Output is byte-equivalent to the previous ClipPipeline path.
• apply_spotlight_vector — same pattern but with the inverted mask. Analytic shapes use cached_mask_texture_inverted; the path variant routes through path_clip.apply in invert: true mode (the cached path-mask doesn't have an inverted form yet — straightforward future extension).

Auto-dispatch path NOT refactored

render_stage auto-dispatches Container::clip = Some(MaskShape) through the inline ClipPipeline directly. That path is hot — called per dispatched node every frame — and the existing single- shader implementation already optimizes it. The vector-mask refactor adds an extra render pass per call which is fine for explicit primitives (offset by mask cache hits) but would be a regression on the hot path. The auto-dispatch keeps using the inline clip pipeline; explicit apply_clip calls go through the new path.

API

• wisp::Renderer::apply_clip
• wisp::Renderer::apply_clip_vector
• wisp::Renderer::apply_spotlight
• wisp::Renderer::apply_spotlight_vector