Calculation on the flowchart may visualize the process of calculation
and make easy to understand than the calculation on a spread sheet. I wish
to call it visual calculation. Now, I've created Visio shapes for such
visual calculation. Here are shapes for decimal and logical calculculation.
And here you can find many other shapes. For example Visio Word Art, Magnifier,
User Cells Editor, and so on.
I am now creating shapes for Perspective drawing
Here are shapes for 1-point, 2-point and 3-point perspective view.
I am now studing projective geometry to understand more about perspective drawing. And I found any quadrangle can be the projection of a square, if view point
is selected properly. You can see this in pdf document, in Visio.drawing
or in Java applet.