Dynamic Geometry Preview

The geometry construction has been provided with a Dynamic Preview Function. This function provides a visual check on the construction before it is actually performed. If there are several solutions to a construction (which is often the case) moving the screen cursor will select the nearest solution and the new element will be shown in white. When the correct solution is shown, a click with the left hand mouse button will carry out the construction. The new element will then be drawn in green.

In the following example we will look at the construction of a circle that must lie tangential to three existing circles.

If you look at the graphic below you can see that two tangent points have already been chosen. The final construction has two possible solutions, depending upon which side of the third circle is picked. As the screen cursor is moved nearest to one side or the other, the possible new circle will be shown in white.

When the circle selected is the correct one, a click with the left hand mouse button will carry out the construction. The circle will be drawn in green as normal.