// MIRROR QUAD — the frame folds across BOTH axes at once, four mirrored
// quadrants of one source; SHIFT recentres the fold, SCALE zooms first.
{
    name: "Mirror Quad"
    engine: "screen"
    input0: "test"

    p0: 0.5  p1: 0.5  p2: 0.5
    dials: [
        {name: "SCALE", bind: "p0", default: 0.5},
        {name: "SHIFT", 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 ang = self.time_beat.x * 0.05 * (0.2 + 1.6 * self.user.z)
            let cs = cos(ang)
            let sn = sin(ang)
            let scale = 0.2 + 1.6 * self.user.x
            let c0 = uv - vec2(0.5, 0.5)
            let c1 = vec2(c0.x * cs - c0.y * sn, c0.x * sn + c0.y * cs) / scale
            let sh = (self.user.y - 0.5) * 0.6
            let c2 = c1 + vec2(sh, sh)
            let f = vec2(abs(c2.x), abs(c2.y))
            let w = f + 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)
        }
    }
}