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Converts 16-bit 8:8 Fixed Point numbers to swift Doubles.
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| /** | |
| Converts 16-bit 8:8 Fixed Point numbers to swift Doubles. | |
| Fixed Point mathematical functions: | |
| <https://courses.cit.cornell.edu/ee476/Math/> | |
| Compare the results from these calls to the Examples from the "Fixed Point mathematical functions" paper. | |
| Double.from88FixedPoint(0, 0) | |
| Double.from88FixedPoint(1, 0) | |
| Double.from88FixedPoint(1, 128) | |
| Double.from88FixedPoint(1, 192) | |
| Double.from88FixedPoint(1, 1) | |
| Double.from88FixedPoint(255, 0) | |
| Double.from88FixedPoint(254, 128) | |
| Double.from88FixedPoint(254, 0) | |
| Double.from88FixedPoint(129, 0) | |
| Double.from88FixedPoint(255, 128) | |
| Double.from88FixedPoint(255, 192) | |
| Double.from88FixedPoint(0, 128) | |
| Double.from88FixedPoint(128, 0) | |
| Double.from88FixedPoint(127, 0) | |
| Double.from88FixedPoint(2, 64) | |
| Double.from88FixedPoint(253, 192) | |
| <https://gist.github.com/tannernelson/24030969dacc6d9b4885> | |
| */ | |
| extension Double { | |
| static func from88FixedPoint(byte1: UInt8, _ byte2: UInt8) -> Double { | |
| var double: Double = 0 | |
| var integer = Double(byte1) | |
| var fraction = Double(byte2) | |
| if integer >= 256 / 2 { | |
| integer -= 256 | |
| } | |
| double += Double(integer) | |
| double += (1 / 256) * Double(fraction) | |
| return double | |
| } | |
| } |
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