Learn how you can draw an "imaginary box" and then replace the box with 3-D everyday objects. You can learn to do just that by watching this video. There are hundreds and hundreds of objects that you will be able to draw after learning how to draw this imaginary box and build off of it. You can draw a floor lamp, a refrigerator, a house and so much more just by using this neat artist' tip. The lines of the box help you to center your picture and make it look more realistic and the shading is what will bring your picture to life.





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Note added at 1 hora (2011-11-20 18:12:16 GMT)
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The Two Approaches to Drawing Structure
There are two main approaches to drawing structure. The first is to start with basic skeleton and add detail, visualizing the basic shapes that underly a complex surface, like a sculptor working in clay and adding pieces on. The second method involves an imaginary box, working from the outside in, imagining basic shapes that the form fits within, like a sculptor starting with a block of marble and chipping bits away.
http://drawsketch.about.com/cs/drawinglessons/a/drawstructur...

There are five basic geometric shapes, when combined, can be the basis from which any drawing can be made .
The shape is sketched and an object approximating the shape is drawn within the outline.