// PETAL FOLD — the frame folds around the centre into LEAVES angular
// wedges, each a mirror of one reference sector, like an opening flower.
{
    name: "Petal Fold"
    engine: "screen"
    input0: "test"

    p0: 0.5  p1: 0.5  p2: 0.5
    dials: [
        {name: "LEAVES", bind: "p0", default: 0.5},
        {name: "FOLD", bind: "p1", default: 0.5},
        {name: "SPIN", bind: "p2", default: 0.5}
    ]

    stages: [
        {kind: "bloom", threshold: 0.6, strength: 1.05, levels: 2}
    ]

    shader: draw.DrawVjFxScreen {
        fx_color: fn(uv: vec2, content: vec4, cmix: float) -> vec4 {
            let center = vec2(0.5, 0.5)
            let d = uv - center
            let r = length(d)
            let ang = atan2(d.y, d.x)
            let leaves = floor(3.0 + 9.0 * self.user.x)
            let sector = 6.2831853 / leaves
            let spin = modf(self.time_beat.y * 0.02 * (0.2 + 1.6 * self.user.z), sector)
            let raw = modf(ang + 3.14159265 + spin, sector)
            let mirrored = mix(raw, sector - raw, clamp(self.user.y, 0.0, 1.0))
            let w = center + vec2(cos(mirrored), sin(mirrored)) * r
            let tex = self.tex0.sample_as_bgra(clamp(w, vec2(0.0, 0.0), vec2(1.0, 1.0)))
            return vec4(tex.xyz, 1.0)
        }
    }
}