CanvasPlus (derived from Cavas by Sean Dougherty)
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This is basically the same thing as the original canvas with a few new additions.
There is now the ability to draw circles and rectangles.

addPoint(String caption, float x, float y)
	creates a point at (x,y) and captions it

addLine(float x1, float y1, float x1, float y2)
	creates a line from (x1,y1) to (x2,y2)

addCross(float x, float y, float radius)
	creates a uniform cross at (x,y) that extends radius in the 4 cardinal directions

addCircle(float x, float y, float r)
	creates a circle at (x,y) with radius r

addRectangle(float xCenter, float yCenter, float xHeight, float yWidth)
	creates a rectangle created by the corner points ((xCenter +/- xHeight) , (yCenter +/- yHeight))
