EnvironmentGallery

The eight bundled CC0 HDRI environments (studio, courtyard, forest, interior, city, sunrise, sunset, night) stepped through over one PBR still life. They advance on their own, or you can step with the arrow keys.

Run

swift run --package-path Examples Example-3D-Environments-EnvironmentGallery

Source

Examples/3D/Environments/EnvironmentGallery/Sketch.swift

import Ollin

/// The bundled environment library, one at a time.
///
/// Ollin bundles eight CC0 HDRI environments for image-based lighting (a studio, a
/// courtyard, a forest, an interior, a city, a sunrise, a sunset, a night), all offline and
/// instant. This gallery steps through them (every few seconds, or press the left/right
/// arrows), lighting the same three physically-based balls (a polished chrome, a brushed
/// gold, and a smooth dielectric) in each, with the environment shown behind them so you can
/// see what they're reflecting. (A dozen more (`.photoStudio`, `.day`, `.dusk`, …) download
/// on demand; `Environment.allBuiltins` lists the full curated set.)
@main
final class EnvironmentGallery: Sketch {

    var offset = 0   // arrow-key stepping, added to the time-based auto-advance

    let balls: [(material: Material, fill: Color, x: Double)] = [
        (.polishedMetal,             .white,                                            -2.5),
        (.metal(roughness: 0.32),    Color(hue: 0.09, saturation: 0.45, brightness: 0.95), 0),
        (.dielectric(roughness: 0.4), Color(hue: 0.58, saturation: 0.55, brightness: 0.9),  2.5),
    ]

    override func draw() {
        let all = Environment.bundledBuiltins
        // Time-based so it's deterministic (a given frame always shows the same one);
        // the arrow keys shift `offset`. Auto-advances every 3 seconds.
        let index = ((Int(time / 3.0) + offset) % all.count + all.count) % all.count
        let entry = all[index]

        background(.black)
        toneMap(.aces)   // a filmic highlight rolloff for the HDR environments
        cameraShowcase(.sway(amplitude: 0.35, period: .tau / 0.15), target: .zero, radius: 7.5,
                    elevation: 0.1, fieldOfView: .pi / 4.2)

        // The current environment lights the balls and shows as the backdrop, spinning
        // slowly so the reflections drift.
        environment(entry.environment.rotated(time * 0.08))

        for ball in balls {
            withState {
                translate(ball.x, 0, 0)
                fill(ball.fill)
                material(ball.material)
                drawSphere(radius: 0.95)
            }
        }

        // The environment's name and position, as a 2D overlay over the 3D scene.
        withState {
            textFont(OutlineFont.system)
            textSize(34)
            textAlign(.center)
            noStroke()
            fill(.white)
            drawText("\(entry.name)    \(index + 1)/\(all.count)",
                     at: Vector2(Double(width) / 2, Double(height) - 80))
        }
    }

    override func keyPressed() {
        if keyCode == .leftArrow  { offset -= 1 }
        if keyCode == .rightArrow { offset += 1 }
    }
}