Math

HEMTT includes a built-in mathematical expression evaluator used in config files. This allows you to use arithmetic operations, trigonometric functions, and angle conversions directly in config values, reducing the need for manual calculations or __EVAL.

The evaluator is automatically applied when parsing config files, allowing expressions like value = 1 + 2; to be evaluated to value = 3;.

Supported Operators

Arithmetic Operators

Operator	Description	Example
`+`	Addition	`2 + 3` → `5`
`-`	Subtraction	`5 - 2` → `3`
`*`	Multiplication	`2 * 3` → `6`
`/`	Division	`6 / 2` → `3`
`^`	Exponentiation	`2 ^ 3` → `8`
`%`	Modulo	`5 % 2` → `1`

Operator Precedence

Operations follow standard mathematical precedence:

Unary minus (negation): -x
Exponentiation: ^
Multiplication, Division, Modulo: *, /, %
Addition, Subtraction: +, -

Parentheses can be used to override precedence:

1 + 2 * 3        → 7
(1 + 2) * 3      → 9

Functions

Trigonometric Functions

All trigonometric functions work with radians.

Function	Description	Example
`sin(x)`	Sine	`sin(0)` → `0`
`cos(x)`	Cosine	`cos(0)` → `1`
`tan(x)` or `tg(x)`	Tangent	`tan(0)` → `0`
`asin(x)`	Arcsine	`asin(1)` → `1.5708...` (π/2)
`acos(x)`	Arccosine	`acos(1)` → `0`
`atan(x)` or `atg(x)`	Arctangent	`atan(0)` → `0`

Angle Conversion Functions

Function	Description	Example
`rad(x)`	Convert degrees to radians	`rad(180)` → `3.14159...` (π)
`deg(x)`	Convert radians to degrees	`deg(pi)` → `180`

Constants

Constant	Value
`pi`	3.14159265…

Examples

Basic Calculations

1 + 1                    → 2
10 - 3                   → 7
4 * 5                    → 20
20 / 4                   → 5
2 ^ 10                   → 1024
17 % 5                   → 2

With Parentheses

(1 + 2) * 3              → 9
1 + (2 * 3)              → 7
((2 + 3) * 4) - 1        → 19

Negative Numbers

-5                       → -5
1 + -2                   → -1
1 - -2                   → 3
2 * -(3 + 1)             → -8

Trigonometric

sin(0)                   → 0
cos(0)                   → 1
sin(pi / 2)              → 1
cos(pi)                  → -1
tan(0)                   → 0

Angle Conversion

rad(90)                  → 1.5708... (π/2)
rad(180)                 → 3.14159... (π)
deg(pi)                  → 180
deg(pi / 2)              → 90

Complex Expressions

2 * sin(pi / 6)          → 1 (sin(30°) = 0.5)
deg(atan(1))             → 45
cos(rad(60)) + sin(rad(30))  → 1
(pi * 2) ^ 2             → 39.478...

With Constants

pi                       → 3.14159...
2 * pi                   → 6.28318... (circumference factor)
pi * 5 ^ 2               → 78.539... (area of circle with radius 5)

Arma Config Examples

Since this evaluator is used in Arma 3 config files, here are practical examples of how to use math expressions in your configurations:

Basic Config Values

class MyClass {
    // Simple arithmetic
    cost = 100 + 50;                     // Evaluates to 150
    multiplier = 2 * 3.5;                // Evaluates to 7
    
    // Damage calculations
    maxDamage = 100 / 2;                 // Evaluates to 50
    armorCoefficient = 1 / 0.8;          // Evaluates to 1.25
};

Using Constants and Functions

class MyWeapon {
    // Angles and rotations
    rotationAngle = rad(45);             // Convert 45° to radians
    deploymentAngle = deg(pi / 4);       // Convert π/4 radians to degrees
    
    // Trigonometric calculations
    offsetX = cos(rad(45)) * 2;
    offsetY = sin(rad(30)) * 5;
};

Invalid expressions will return an error:

1 +                      → Error (incomplete expression)
(1 + 1                   → Error (mismatched parentheses)
1 & 1                    → Error (invalid operator)

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