Interactive Models Based on Virtual Reality Technology Used in Civil Engineering Education - Teaching through Multi-User Virtual Environments - page 406

Figure 22. Perspective and drawing of a roof

Figure 23. Initial outline of the roof and gradient of roof planes and the breakdown into two quadrangles

In order to define the virtual environment for the
simulation a 3D representation of all its constitu-
ent elements was required. The modeling was
carried out using AutoCAD . The components thus
generated were rendered by the virtual reality
system EON Studio , leading to the definition of
the desired interactive animation.
The model was programmed to show the de-
tailed construction of the roof over one of the
trapezoidal bases followed by the process of in-
tersecting the two blocks. Thus solid models had
to be used in order to achieve 3D representation
(Figure 24):

• Two individualized wire-frame trapezoids

(the base of two roofs composed of four
planes);

• Two right-angled triangles representing

the established value for the slopes of each
water-plane (1:1 e 2:3);

• The unitary elevation roof lines with ho-

mogeneous elevation for each of the roof
planes, referring to one of the roof block,
forming a closed polygonal line;

• The surfaces of 4 roof water planes for

each of the block.

The programmed sequence is supported on the
didactic way of explaining this issue to students,
and reflects the real methodology by which the