// BEAM FAN — twelve thin video beams pivoting through one centre like a
// folding hand of cards: each slat carries its own horizontal band of the
// clip (`uv_split: "bands_y"`), the fan opens and closes on slow sines and
// the whole hand swings, so the picture keeps almost assembling and then
// shearing into rays of light. Pattern taught here: thin `grid` slats +
// band windows + a rotation-only fx_place with per-slat z offsets to keep
// the crossing beams from fighting.
{
    name: "Beam Fan"
    engine: "videomesh"
    shape: "grid"
    seed: 12

    instances: 12
    uv_split: "bands_y"
    size: 2.6
    aspect: 0.085
    spread: 0.6
    fly: 0.4
    alt: 0.3

    beat_pulse: 0.45
    input0: "test"

    color_bg: #x05040c
    color_a: #x40c8f0
    color_b: #xb04ff0
    color_c: #xe8f4ff

    fog: 0.0
    glow: 1.0

    stages: [
        {kind: "bloom", threshold: 0.6, strength: 1.1, levels: 3}
    ]

    // THE LOOK LIVES HERE — the fan placement (angle per slat, breathing
    // spread, swinging root) and the beam fragment.
    shader: draw.DrawVjFxVideomesh {
        fx_axis: fn(id: float, hash: float) -> vec3 {
            return vec3(0.0, 0.0, 1.0)
        }
        fx_place: fn(id: float, hash: float, t: float) -> vec4 {
            let n = max(self.shape.y, 2.0)
            let open = 1.15 + 0.35 * sin(t * 0.33)
            let swing = 0.25 * sin(t * 0.21)
            let ang = (id / (n - 1.0) - 0.5) * open + swing
            return vec4(0.0, 0.0, id * 0.03 - n * 0.015, ang)
        }
        fx_color: fn(t: float, attr: vec4, content: vec4, cmix: float) -> vec4 {
            let lit = content.xyz * t
            let ray = self.col_a.xyz.mix(self.col_b.xyz, attr.w / max(self.shape.y, 1.0))
                * (1.0 - attr.z)
                * (0.35 + self.time_beat.w * 1.2 + clamp(self.user.z, 0.0, 4.0))
            return vec4((lit + ray) * self.fog.y, 1.0)
        }
    }
}