Math-Helper-Functions
Some useful Math functions not built into the Javascript Math Object. Mainly useful for Web Games.
Functions
-
map(x, istart, istop, ostart, ostop) ⇒
Number -
Map a value from a range of numbers to another range of numbers.
x is the intial value between istart and istop and return the value between ostart and ostop
-
limit(x, min, max) ⇒
Number -
Limit a value between a min/max value
-
toRad(x) ⇒
Number -
Convert the angle, provided in degrees (0-360), into radians (0-2*PI)
-
toDeg(x) ⇒
Number -
Convert the angle, provided in radians (0-2*PI), into degrees (0-360)
-
range(min, max) ⇒
Number -
Get random Float value between range of numbers
-
distance(a, b) ⇒
Number -
Distance between two points
-
lerp(current, target, time) ⇒
Number -
Lerp between current position to target position over a period of time
-
average(a, b) ⇒
Number -
Returns the average or the midpoint between two numbers
-
midpoint(v1, v2) ⇒
Object -
Get the midpoint between two points
- chance(percent)
-
Return a true or false for a random chance of a percentage
map(x, istart, istop, ostart, ostop) ⇒ Number
Map a value from a range of numbers to another range of numbers x is to istart and istop segment.
Returns: Number - The number that is in the same relation to ostart and ostop segment
| Param | Type | Description |
|---|---|---|
| x | Number |
Value we are testing |
| istart | Number |
Min value to test |
| istop | Number |
Max value to test |
| ostart | Number |
Min value to map to (based on x value) |
| ostop | Number |
Max value to map to (based on x value) |
Example
map(Math.random(), 0, 1, 10, 20); will provided a number between 10 and 20
limit(x, min, max) ⇒ Number
Limit a value between a min/max value
Returns: Number - Either x, or the nearest limit if x is out of bounds.
| Param | Type | Description |
|---|---|---|
| x | Number |
Value we need to limit |
| min | Number |
Min number to return |
| max | Number |
Max number to return |
toRad(x) ⇒ Number
Convert the angle, provided in degrees (0-360), into radians (0-2*PI)
Returns: Number - Angle in Radians
| Param | Type | Description |
|---|---|---|
| x | Number |
Angle in Degrees |
toDeg(x) ⇒ Number
Convert the angle, provided in radians (0-2*PI), into degrees (0-360)
Returns: Number - Angle in Degrees
| Param | Type | Description |
|---|---|---|
| x | Number |
Angle in Radians |
range(min, max) ⇒ Number
Get random Float value between range of numbers
Returns: Number - Return random Float value between min and max range
| Param | Type | Description |
|---|---|---|
| min | Number |
Min range value |
| max | Number |
Max range value |
distance(a, b) ⇒ Number
Distance between two points
Returns: Number - Distance between points
| Param | Type | Description |
|---|---|---|
| a | Object |
first point {x: 0, y: 0} |
| b | Object |
second point {x: 0, y: 0} |
Example
- can supply 2D or 3D point {x: 0, y: 0, z: 0}
lerp(current, target, time) ⇒ Number
Lerp between current position to target position over a period of time
Returns: Number - Value between current/target over the time
| Param | Type | Description |
|---|---|---|
| current | Number |
Current position value |
| target | Number |
Target position value |
| time | Number |
Time value |
average(a, b) ⇒ Number
Returns the average or the midpoint between two numbers
Returns: Number - - the midpoint between two numbers
| Param | Type | Description |
|---|---|---|
| a | Number |
first number |
| b | Number |
second number |
midpoint(v1, v2) ⇒ Object
Get the midpoint between two points
Returns: Object - - {x: x, y: y, z: z}
| Param | Type | Description |
|---|---|---|
| v1 | Object |
{x: 0, y: 0} |
| v2 | Object |
{x: 0, y: 0} |
Example
- Also accepts 3D point {x: 0, y: 0, z: 0}chance(percent)
Return a true or false for a random chance of a percentage
| Param | Type | Description |
|---|---|---|
| percent | Number |
float percentage 0 -> 1 |
Example
if(chance(0.2)){ console.log('20% chance true') }