Solids > Projections
12345Projections

Theory

When representing a 3D-figure on a flat surface, you are making a projection of the figure on the surface. This often gives distortion. When making a "parallel" projection:

  • edges parallel to the drawing surface are depicted full-scale;

  • parallel edges are depicted parallel;

  • edges that are parallel and of the same length are depicted with the same length (a.o. this means that the center of a line segment also is in the center of the figure).

Here you see a "parallel" projection of a cube A B C D . E F G H . The edges A B , B F , F E , A E and D C , C G , G H , D H are parallel to the drawing surface and therefore full-scale. The squares A B F E and D C H G are square in the drawing as well. The edges B C , F G , A D , E H are parallel in the drawing as well. They have been shortened to make the figure really look like a cube. On a blank page you work with an angle and a scaling factor.

You will see the most important solids by clicking in the figure.

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