// BAR MAGNIFIER — a horizontal and a vertical bar-shaped lens crossing the
// centre; ORIENT sweeps from a pure H bar through a cross to a pure V bar.
{
    name: "Bar Magnifier"
    engine: "screen"
    input0: "test"

    p0: 0.5  p1: 0.5  p2: 0.5
    dials: [
        {name: "WIDTH", bind: "p0", default: 0.5},
        {name: "POWER", bind: "p1", default: 0.5},
        {name: "ORIENT", 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 halfw = 0.04 + 0.22 * self.user.x
            let mag = 1.0 + 3.0 * self.user.y * (0.6 + 0.4 * self.time_beat.w)
            let center = 0.5
            let dy = uv.y - center
            let insideh = 1.0 - smoothstep(halfw * 0.7, halfw, abs(dy))
            let zx = center + (uv.x - center) / mag
            let dx = uv.x - center
            let insidev = 1.0 - smoothstep(halfw * 0.7, halfw, abs(dx))
            let zy = center + (uv.y - center) / mag
            let orient = clamp(self.user.z, 0.0, 1.0)
            let wh = 1.0 - orient
            let wv = orient
            let w = vec2(mix(uv.x, zx, insideh * wh), mix(uv.y, zy, insidev * wv))
            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)
        }
    }
}