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diff --git a/qtruby/rubylib/examples/ruboids/ruboids/Point.rb b/qtruby/rubylib/examples/ruboids/ruboids/Point.rb
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+#
+# Copyright (c) 2001 by Jim Menard <jimm@io.com>
+#
+# Released under the same license as Ruby. See
+# http://www.ruby-lang.org/en/LICENSE.txt.
+#
+
+class Point
+
+    attr_accessor :x, :y, :z
+
+    # Return a new Point that is the midpoint on the line between two
+    # points.
+    def Point.midpoint(a, b)
+	return Point.new((a.x + b.x) * 0.5, (a.y + b.y) * 0.5,
+			   (a.z + b.z) * 0.5)
+    end
+
+    def initialize(x = 0, y = 0, z = 0)
+	if x.kind_of?(Point)
+	    @x = x.x
+	    @y = x.y
+	    @z = x.z
+	else
+	    @x = x
+	    @y = y
+	    @z = z
+	end
+    end
+
+    ORIGIN = Point.new(0, 0, 0)
+
+    def ==(point)
+	return point.kind_of?(Point) &&
+	    @x == point.x && @y == point.y && @z == point.z
+    end
+
+    # Normalize this point.
+    def normalize!
+	mag = @x * @x + @y * @y + @z * @z
+	if mag != 1.0
+	    mag = 1.0 / Math.sqrt(mag)
+	    @x *= mag
+	    @y *= mag
+	    @z *= mag
+	end
+	return self
+    end
+
+    # Return a new point that is a normalized version of this point.
+    def normalize
+	return self.dup().normalize!()
+    end
+
+    # Return a new point that is the cross product of this point and another.
+    # The cross product of two unit vectors is another vector that's at
+    # right angles to the first two (for example, a surface normal).
+    def crossProduct(p)
+	return Point.new(@y * p.z - @z * p.y, @z * p.x - @x * p.z,
+			 @x * p.y - @y * p.x)
+    end
+
+    # Return the (scalar) dot product of this vector and another.
+    # The dot product of two vectors produces the cosine of the angle
+    # between them, multiplied by the lengths of those vectors. (The dot
+    # product of two normalized vectors equals cosine of the angle.)
+    def dotProduct(p)
+	return @x * p.x + @y * p.y + @z * p.z
+    end
+
+    # Return square of distance between this point and another.
+    def squareOfDistanceTo(p)
+	dx = p.x - @x
+	dy = p.y - @y
+	dz = p.z - @z
+	return dx * dx + dy * dy + dz * dz
+    end
+
+    # Return distance between this point and another.
+    def distanceTo(p)
+	dx = p.x - @x
+	dy = p.y - @y
+	dz = p.z - @z
+	return Math.sqrt(dx * dx + dy * dy + dz * dz)
+    end
+
+    def add(d)
+	@x += d
+	@y += d
+	@z += d
+	return self
+    end
+
+    def addPoint(p)
+	@x += p.x
+	@y += p.y
+	@z += p.z
+	return self
+    end
+
+
+    def subtract(d)
+	@x -= d
+	@y -= d
+	@z -= d
+	return self
+    end
+
+    def subtractPoint(p)
+	@x -= p.x
+	@y -= p.y
+	@z -= p.z
+	return self
+    end
+
+
+    def multiplyBy(d)
+	@x *= d
+	@y *= d
+	@z *= d
+	return self
+    end
+
+    def multiplyByPoint(p)
+	@x *= p.x
+	@y *= p.y
+	@z *= p.z
+	return self
+    end
+
+    def divideBy(d)
+	@x = @x / d
+	@y = @y / d
+	@z = @z / d
+	return self
+    end
+
+    def divideByPoint(p)
+	@x = @x / p.x
+	@y = @y / p.y
+	@z = @z / p.z
+	return self
+    end
+
+    def to_a
+	return [@x, @y, @z]
+    end
+
+    def to_s
+	return "Point<#{@x}, #{@y}, #{@z}>"
+    end
+
+end