19 lines
626 B
CoffeeScript
19 lines
626 B
CoffeeScript
|
# Vertice operations.
|
||
|
|
|
||
|
|
# **Vertice** is a utility class to help with vertice operations. A vertice
|
||
|
|
# is implemented as a 2-element array. Element 0 is *x* and element 1 is *y*.
|
||
|
|
|
||
|
|
# Translate a vertice from an origin point using rotation and scale.
|
||
|
|
export translate = (v, origin, rotation = 0, scale = 1) ->
|
||
|
|
|
||
|
|
difference = [v[0] - origin[0], v[1] - origin[1]]
|
||
|
|
magnitude = scale * Math.sqrt(
|
||
|
|
difference[0] * difference[0] + difference[1] * difference[1]
|
||
|
|
)
|
||
|
|
rotation += Math.atan2 difference[1], difference[0]
|
||
|
|
|
||
|
|
return [
|
||
|
|
origin[0] + Math.cos(rotation) * magnitude
|
||
|
|
origin[1] + Math.sin(rotation) * magnitude
|
||
|
|
]
|