56 lines
916 B
Go
56 lines
916 B
Go
package s2
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// DefaultLevel specifies the default S2 cell size.
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var DefaultLevel = 21
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// Level returns the applicable cell level based on the search range in km,
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// see https://s2geometry.io/resources/s2cell_statistics.html.
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func Level(km float64) (level int) {
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switch {
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case km >= 7842:
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return 0
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case km >= 3921:
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return 1
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case km >= 1825:
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return 2
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case km >= 1130:
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return 3
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case km >= 579:
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return 4
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case km >= 287:
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return 5
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case km >= 143:
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return 6
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case km >= 72:
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return 7
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case km >= 36:
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return 8
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case km >= 18:
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return 9
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case km >= 9:
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return 10
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case km >= 4:
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return 11
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case km >= 2:
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return 12
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case km >= 1:
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return 13
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case km >= 0.425:
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return 14
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case km >= 0.212:
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return 15
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case km >= 0.106:
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return 16
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case km >= 0.053:
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return 17
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case km >= 0.027:
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return 18
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case km >= 0.013:
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return 19
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case km >= 0.007:
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return 20
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default:
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return DefaultLevel
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}
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}
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