Download this applet for off-line viewing (includes source code)
Drag any movable point to a different position or click on any point, line and/or circle to change it's color. Drag any other region to view the sphere from a different position.
Click anywhere on the applet to create a new movable point. You may also drag any pre-existing movable point to a new position. If the mouse is over a point, the point will be highlighted.
Click on any two distinct points, A and B. Draws the line through A and B. Note that B cannot be the polar opposite (antipode) of A.
Click on any two distinct points, A and B. Draws the line segment with endpoints A and B. For the purposes of the following descriptions, a line segment is considered to be a line while a line is not a line segment.
Click on any two distinct points, A and B. Draws the circle centered at A that goes through B.
Click on any two lines and/or circles. If the two objects you selected intersect, the points of intersection will be drawn. In the case of the intersection of a line and a circle or the intersection of two circles, this may result in two points of intersection.
Click on any point, A. Draws the polar opposite of A.
Click on any two distinct points, A and B. Draws the midpoint of A and B.