gg/mx/math.go

package mx

import (
	"math"
)

// The type is used in all Engine interactions
// where you need floating values to keep
// it interchangable in future.
// Not much promise for this though.
type Float = float64

const (
	MaxFloat Float = math.MaxFloat64
	Pi Float = math.Pi
	RadDegrees Float = 57.2958
	//PiRad = Pi * Rad
	EqualityThreshold Float = 1e-9
)

func IsNan(v Float) bool {
	return math.IsNaN(v)
}

func IsInf(f Float, sign int) bool {
	return math.IsInf(f, sign)
}

func Degree(f Float) Float {
	return (f/(2*Pi))*360
}

// Returns square of the value.
func Sqr(v Float) Float {
	return v * v
}

func Sqrt(v Float) Float {
	return math.Sqrt(v)
}

func Asin(v Float) Float {
	return math.Asin(v)
}

func Atan(v Float) Float {
	return math.Atan(v)
}

func Sgn(v Float) Float {
	if v > 0 {
		return 1
	}
	
	if v < 0 {
		return -1
	}
	
	return 0
}

func Max(v1, v2 Float) Float {
	if v1 > v2 {
		return v1
	}
	
	return v2
}

func Min(v1, v2 Float) Float {
	if v1 < v2 {
		return v1
	}
	
	return v2
}

func Abs(v Float) Float {
	if v >= 0 {
		return v
	}
	return -v
}

func RadiansToDegrees(v Float) Float {
	return v/Pi * 180
}

func DeegresToRadians(v Float) Float {
	return v
}

// Returns whether the two floats are nearly equal.
func Neq(a, b Float) bool {
	return Abs(a-b) <= EqualityThreshold
}