// ROTO BOUNCE — rotozoom whose ZOOM rides a beat-synced bounce arc: it
// snaps in tight on the beat and eases back out before the next one.
{
    name: "Roto Bounce"
    engine: "screen"
    input0: "test"

    p0: 0.5  p1: 0.5  p2: 0.5
    dials: [
        {name: "SPIN", bind: "p0", default: 0.5},
        {name: "ZOOM", bind: "p1", default: 0.5},
        {name: "BOUNCE", 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 pi = 3.14159265
            let spin = 0.16 * (0.2 + 1.6 * self.user.x)
            let ang = self.time_beat.x * spin
            let cs = cos(ang)
            let sn = sin(ang)
            let bounce_pow = 0.5 + 1.4 * self.user.z
            let bounce = pow(abs(sin(self.time_beat.z * pi)), bounce_pow)
            let zoom = (0.2 + 1.6 * self.user.y) * (0.7 + 0.6 * bounce)
            let c = uv - vec2(0.5, 0.5)
            let r = vec2(c.x * cs - c.y * sn, c.x * sn + c.y * cs) / zoom
            let w = r + vec2(0.5, 0.5)
            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)
        }
    }
}