18 lines
729 B
Swift
18 lines
729 B
Swift
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import Foundation
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import CoreGraphics
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/// Maps a measured round-trip time (ms) to a radial distance from downtown.
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/// A log curve so the busy near range (1–50ms LAN/CDN) spreads out instead of
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/// bunching at the center, while the long tail (transcontinental) saturates.
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public enum LatencyLayout {
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public static let minRadius: CGFloat = 150
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public static let maxRadius: CGFloat = 560
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public static let rttCeiling: Double = 250 // ms mapped to the outer edge
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public static func radius(forRTT rtt: Double) -> CGFloat {
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let clamped = max(0, min(rtt, rttCeiling))
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let norm = log10(1 + clamped) / log10(1 + rttCeiling)
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return minRadius + CGFloat(norm) * (maxRadius - minRadius)
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}
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}
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