added Circle functions [Tested].

init.moon

@@ -908,6 +908,48 @@ getAngle = (x1, y1, x2, y2, x3, y3) ->
 
 getPercentage = (percent, n) ->
   percent * n
+
+getCircleArea = (radius) ->
+  math = math
+  math.pi * (radius * radius)
+
+getCircumference = (radius) ->
+  math = math
+  2 * math.pi * radius
+
+getCircleCircleIntersection = (circle1x, circle1y, radius1, circle2x, circle2y, radius2) ->
+  length = getLength(circle1x, circle1y, circle2x, circle2y)
+  if length > radius1 + radius2 then return false
+
+  if checkFuzzy(length, 0) and checkFuzzy(radius1, radius2) then return 'equal'
+  if checkFuzzy(circle1x, circle2x) and checkFuzzy(circle1y, circle2y) then return 'collinear'
+
+  a = (radius1 * radius1 - radius2 * radius2 + length * length) / (2 * length)
+  h = math.sqrt(radius1 * radius1 - a * a)
+
+  p2x = circle1x + a * (circle2x - circle1x) / length
+  p2y = circle1y + a * (circle2y - circle1y) / length
+  p3x = p2x + h * (circle2y - circle1y) / length
+  p3y = p2y - h * (circle2x - circle1x) / length
+  p4x = p2x - h * (circle2y - circle1y) / length
+  p4y = p2y + h * (circle2x - circle1x) / length
+
+  if validateNumber(p3x) == false or validateNumber(p3y) == false or 
+    validateNumber(p4x) == false or 
+    validateNumber( p4y ) == false
+    return 'inside'
+
+  if checkFuzzy(length, radius1 + radius2) or 
+    checkFuzzy(length, math.abs(radius1 - radius2))
+    return 'tangent', p3x, p3y
+
+  return 'intersection', p3x, p3y, p4x, p4y
+
+isCircleCompletelyInsideCircle = (circle1x, circle1y, circle1radius, circle2x, circle2y, circle2radius) ->
+  if checkCirclePoint(circle1x, circle1y, circle2x, circle2y, circle2radius) == false then return false
+  Type = getCircleCircleIntersection(circle2x, circle2y, circle2radius, circle1x, circle1y, circle1radius)
+  if (Type ~= 'tangent' and Type ~= 'collinear' and Type ~= 'inside') then return false
+  return true
 
 { 
   point: {
@@ -957,6 +999,23 @@ getPercentage = (percent, n) ->
     getPercentage: getPercentage
   }
 
+  circle: {
+    getArea: getCircleArea
+    checkPoint: checkCirclePoint
+    isPointOnCircle: isPointOnCircle
+    getCircumference: getCircumference
+    getLineIntersection: getCircleLineIntersection
+    getSegmentIntersection: getCircleSegmentIntersection
+    getCircleIntersection: getCircleCircleIntersection
+    isCircleCompletelyInside: isCircleCompletelyInsideCircle
+    isPolygonCompletelyInside: isPolygonCompletelyInsideCircle
+    isSegmentCompletelyInside: isSegmentCompletelyInsideCircle
+
+    getPolygonIntersection: getPolygonCircleIntersection
+    isCircleInsidePolygon: isCircleInsidePolygon
+    isCircleCompletelyInsidePolygon: isCircleCompletelyInsidePolygon
+  }
+
 
   vec2D: -> assert require 'vec2D'
   vec2DArr: -> assert require 'vec2DArr'

mm_spec.moon

@@ -534,4 +534,50 @@ describe "math.getAngle", ->
   it " :: Gives roots given a, b, and c.", ->
     math = mm.math
     assert.fuzzyEqual math.getAngle(1, 3, 1, 1, 3, 1), 1.57079633
-    assert.fuzzyEqual math.getAngle(4, 4, 1, 1, 4, 1), 0.785398163
+    assert.fuzzyEqual math.getAngle(4, 4, 1, 1, 4, 1), 0.785398163
+
+
+describe "circle.getArea", ->
+  it " :: Gives the area of the circle.", ->
+    circle = mm.circle
+    assert.fuzzyEqual circle.getArea(1), 3.14159
+    assert.fuzzyEqual circle.getArea(2), 12.56637
+    assert.fuzzyEqual circle.getArea(5), 78.53981
+    assert.fuzzyEqual circle.getArea(10), 314.15926
+    assert.fuzzyEqual circle.getArea(20), 1256.63706
+
+
+describe "circle.getCircumference", ->
+  it " :: Gives the circumference of the circle.", ->
+    circle = mm.circle
+    assert.fuzzyEqual circle.getCircumference(1), 6.28318
+    assert.fuzzyEqual circle.getCircumference(2), 12.56637
+    assert.fuzzyEqual circle.getCircumference(5), 31.41592
+    assert.fuzzyEqual circle.getCircumference(10), 62.83185
+    assert.fuzzyEqual circle.getCircumference(20), 125.66370
+
+describe "circle.getCircleIntersection", ->
+  it " :: Returns \'Equal\' if the circles are the same.", ->
+    circle = mm.circle
+    assert.equal circle.getCircleIntersection( 0, 0, 4, 0, 0, 4 ), 'equal'
+
+  it " :: Returns \'collinear\' if circles have same x and y but not radii.", ->
+    circle = mm.circle
+    assert.equal circle.getCircleIntersection( 0, 0, 4, 0, 0, 8 ), 'collinear'
+    assert.equal circle.getCircleIntersection( 0, 0, 8, 0, 0, 4 ), 'collinear'
+
+  it " :: Returns \'inside\' if the circles are inside but not touching one another.", ->
+    circle = mm.circle
+    assert.equal circle.getCircleIntersection( 1, 1, 2, 2, 1, 4 ), 'inside'
+
+  it " :: Returns false if the point is not within the cirlce.", ->
+    circle = mm.circle
+    assert.false circle.getCircleIntersection( 4, 4, 1, 6, 6, 1 )
+
+
+describe "circle.isCircleCompletelyInside", ->
+  it " :: Returns if a circle is completely inside of another circle.", ->
+    circle = mm.circle
+    assert.true circle.isCircleCompletelyInside( 1, 1, 2, 2, 1, 4 )
+    assert.true circle.isCircleCompletelyInside( 1, 1, 3, 2, 1, 4 )
+    assert.false circle.isCircleCompletelyInside( 8, 2, .1, 2, 1, 4 )