Add documentation for Vector

lib/cyberarm_engine/vector.rb

@@ -1,25 +1,61 @@
 module CyberarmEngine
   class Vector
+    ##
+    # Creates a up vector
+    #
+    #   Vector.new(0, 1, 0)
+    #
+    # @return [CyberarmEngine::Vector]
     def self.up
       Vector.new(0, 1, 0)
     end
 
+    ##
+    # Creates a down vector
+    #
+    #   Vector.new(0, -1, 0)
+    #
+    # @return [CyberarmEngine::Vector]
     def self.down
       Vector.new(0, -1, 0)
     end
 
+    ##
+    # Creates a left vector
+    #
+    #   Vector.new(-1, 0, 0)
+    #
+    # @return [CyberarmEngine::Vector]
     def self.left
       Vector.new(-1, 0, 0)
     end
 
+    ##
+    # Creates a right vector
+    #
+    #   Vector.new(1, 0, 0)
+    #
+    # @return [CyberarmEngine::Vector]
     def self.right
       Vector.new(1, 0, 0)
     end
 
+    ##
+    # Creates a forward vector
+    #
+    #   Vector.new(0, 0, 1)
+    #
+    # @return [CyberarmEngine::Vector]
     def self.forward
       Vector.new(0, 0, 1)
     end
 
+    ##
+    # Creates a backward vector
+    #
+    #   Vector.new(0, 0, -1)
+    #
+    # @return [CyberarmEngine::Vector]
     def self.backward
       Vector.new(0, 0, -1)
     end
@@ -43,6 +79,7 @@ module CyberarmEngine
     alias w weight
     alias w= weight=
 
+    # @return [Boolean]
     def ==(other)
       if other.is_a?(Numeric)
         @x      == other &&
@@ -57,11 +94,13 @@ module CyberarmEngine
       end
     end
 
+    # Create a new vector using {x} and {y} values
+    # @return [CyberarmEngine::Vector]
     def xy
       Vector.new(@x, @y)
     end
 
-    # Performs math operation, excluding @weight
+    # Performs math operation, excluding {weight}
     private def operator(function, other)
       if other.is_a?(Numeric)
         Vector.new(
@@ -78,22 +117,26 @@ module CyberarmEngine
       end
     end
 
-    # Adds Vector and Numberic or Vector and Vector, excluding @weight
+    # Adds Vector and Numeric or Vector and Vector, excluding {weight}
+    # @return [CyberarmEngine::Vector]
     def +(other)
       operator("+", other)
     end
 
-    # Subtracts Vector and Numberic or Vector and Vector, excluding @weight
+    # Subtracts Vector and Numeric or Vector and Vector, excluding {weight}
+    # @return [CyberarmEngine::Vector]
     def -(other)
       operator("-", other)
     end
 
-    # Multiplies Vector and Numberic or Vector and Vector, excluding @weight
+    # Multiplies Vector and Numeric or Vector and Vector, excluding {weight}
+    # @return [CyberarmEngine::Vector]
     def *(other)
       operator("*", other)
     end
 
-    # Divides Vector and Numberic or Vector and Vector, excluding @weight
+    # Divides Vector and Numeric or Vector and Vector, excluding {weight}
+    # @return [CyberarmEngine::Vector]
     def /(other)
       # Duplicated to protect from DivideByZero
       if other.is_a?(Numeric)
@@ -111,6 +154,8 @@ module CyberarmEngine
       end
     end
 
+    # dot product of {Vector}
+    # @return [Integer|Float]
     def dot(other)
       product = 0
 
@@ -124,6 +169,8 @@ module CyberarmEngine
       return product
     end
 
+    # cross product of {Vector}
+    # @return [CyberarmEngine::Vector]
     def cross(other)
       a = self.to_a
       b = other.to_a
@@ -136,24 +183,40 @@ module CyberarmEngine
     end
 
     # returns degrees
+    # @return [Float]
     def angle(other)
       Math.acos( self.normalized.dot(other.normalized) ) * 180 / Math::PI
     end
 
     # returns magnitude of Vector, ignoring #weight
+    # @return [Float]
     def magnitude
       Math.sqrt((@x * @x) + (@y * @y) + (@z * @z))
     end
 
+    ##
+    # returns normalized {Vector}
+    #
+    # @example
+    #   CyberarmEngine::Vector.new(50, 21.2, 45).normalized
+    #   # => <CyberarmEngine::Vector:0x001 @x=0.7089... @y=0.3005... @z=0.6380... @weight=0>
+    #
+    # @return [CyberarmEngine::Vector]
     def normalized
       mag = magnitude
       self / Vector.new(mag, mag, mag)
     end
 
+
+    # returns a direction {Vector}
+    #
+    # z is pitch
+    #
+    # y is yaw
+    #
+    # x is roll
+    # @return [CyberarmEngine::Vector]
     def direction
-      # z is pitch
-      # y is yaw
-      # x is roll
       _x = -Math.sin(@y.degrees_to_radians) * Math.cos(@z.degrees_to_radians)
       _y = Math.sin(@z.degrees_to_radians)
       _z = Math.cos(@y.degrees_to_radians) * Math.cos(@z.degrees_to_radians)
@@ -161,41 +224,63 @@ module CyberarmEngine
       Vector.new(_x, _y, _z)
     end
 
+    # returns an inverse {Vector}
+    # @return [CyberarmEngine::Vector]
     def inverse
       Vector.new(1.0 / @x, 1.0 / @y, 1.0 / @z)
     end
 
+    # Adds up values of {x}, {y}, and {z}
+    # @return [Integer|Float]
     def sum
       @x + @y + @z
     end
 
+    ##
+    # Linear interpolation: smoothly transition between two {Vector}
+    #
+    #   CyberarmEngine::Vector.new(100, 100, 100).lerp( CyberarmEngine::Vector.new(0, 0, 0), 0.75 )
+    #   # => <CyberarmEngine::Vector:0x0001 @x=75.0, @y=75.0, @z=75.0, @weight=0>
+    #
+    # @param other [CyberarmEngine::Vector | Integer | Float] value to subtract from
+    # @param factor [Float] how complete transition to _other_ is, in range [0.0..1.0]
+    # @return [CyberarmEngine::Vector]
     def lerp(other, factor)
       (self - other) * factor.clamp(0.0, 1.0)
     end
 
     # 2D distance using X and Y
+    # @return [Float]
     def distance(other)
       Math.sqrt((@x-other.x)**2 + (@y-other.y)**2)
     end
 
     # 2D distance using X and Z
+    # @return [Float]
     def gl_distance2d(other)
       Math.sqrt((@x-other.x)**2 + (@z-other.z)**2)
     end
 
     # 3D distance using X, Y, and Z
+    # @return [Float]
     def distance3d(other)
       Math.sqrt((@x-other.x)**2 + (@y-other.y)**2 + (@z-other.z)**2)
     end
 
+    # Converts {Vector} to Array
+    # @return [Array]
     def to_a
       [@x, @y, @z, @weight]
     end
 
+    # Converts {Vector} to String
+    # @return [String]
     def to_s
       "X: #{@x}, Y: #{@y}, Z: #{@z}, Weight: #{@weight}"
     end
 
+    # Converts {Vector} to Hash
+    # @return [Hash]
     def to_h
       {x: @x, y: @y, z: @z, weight: @weight}
     end