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CHOMPStation2/code/_helpers/maths.dm

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// Macro functions.
#define RAND_F(LOW, HIGH) (rand()*(HIGH-LOW) + LOW)
#define ceil(x) (-round(-(x)))
// min is inclusive, max is exclusive
/proc/Wrap(val, min, max)
var/d = max - min
var/t = Floor((val - min) / d)
return val - (t * d)
/proc/Default(a, b)
return a ? a : b
// Trigonometric functions.
/proc/Tan(x)
return sin(x) / cos(x)
/proc/Csc(x)
return 1 / sin(x)
/proc/Sec(x)
return 1 / cos(x)
/proc/Cot(x)
return 1 / Tan(x)
/proc/Atan2(x, y)
if(!x && !y) return 0
var/a = arccos(x / sqrt(x*x + y*y))
return y >= 0 ? a : -a
/proc/Floor(x)
return round(x)
/proc/Ceiling(x)
return -round(-x)
// Greatest Common Divisor: Euclid's algorithm.
/proc/Gcd(a, b)
while (1)
if (!b) return a
a %= b
if (!a) return b
b %= a
// Least Common Multiple. The formula is a consequence of: a*b = LCM*GCD.
/proc/Lcm(a, b)
return abs(a) * abs(b) / Gcd(a, b)
// Useful in the cases when x is a large expression, e.g. x = 3a/2 + b^2 + Function(c)
/proc/Square(x)
return x*x
/proc/Inverse(x)
return 1 / x
// Condition checks.
/proc/IsAboutEqual(a, b, delta = 0.1)
return abs(a - b) <= delta
// Returns true if val is from min to max, inclusive.
/proc/IsInRange(val, min, max)
return (val >= min) && (val <= max)
/proc/IsInteger(x)
return Floor(x) == x
/proc/IsMultiple(x, y)
return x % y == 0
/proc/IsEven(x)
return !(x & 0x1)
/proc/IsOdd(x)
return (x & 0x1)
// Performs a linear interpolation between a and b.
// Note: weight=0 returns a, weight=1 returns b, and weight=0.5 returns the mean of a and b.
/proc/Interpolate(a, b, weight = 0.5)
return a + (b - a) * weight // Equivalent to: a*(1 - weight) + b*weight
/proc/Mean(...)
var/sum = 0
for(var/val in args)
sum += val
return sum / args.len
// Returns the nth root of x.
/proc/Root(n, x)
return x ** (1 / n)
// The quadratic formula. Returns a list with the solutions, or an empty list
// if they are imaginary.
/proc/SolveQuadratic(a, b, c)
ASSERT(a)
. = list()
var/discriminant = b*b - 4*a*c
var/bottom = 2*a
// Return if the roots are imaginary.
if(discriminant < 0)
return
var/root = sqrt(discriminant)
. += (-b + root) / bottom
// If discriminant == 0, there would be two roots at the same position.
if(discriminant != 0)
. += (-b - root) / bottom
/proc/ToDegrees(radians)
// 180 / Pi ~ 57.2957795
return radians * 57.2957795
/proc/ToRadians(degrees)
// Pi / 180 ~ 0.0174532925
return degrees * 0.0174532925
// Vector algebra.
/proc/squaredNorm(x, y)
return x*x + y*y
/proc/norm(x, y)
return sqrt(squaredNorm(x, y))
/proc/IsPowerOfTwo(var/val)
return (val & (val-1)) == 0
/proc/RoundUpToPowerOfTwo(var/val)
return 2 ** -round(-log(2,val))