**5.1 Objects geometry in the simulator**

Target devices for wheelchair simulators are virtual headsets, therefore, it is needed to keep objects geometry as simple as possible. The higher is complexity of an object, the more it is compelling for the renderer to process. Every polygon in the object will burden renderer to calculate it and display it on the final screen. Due to this fact, many applications for virtual reality use low polygon technique of modeling. **Figure 10** shows geometry of some objects used in the simulator.

### *3D Computer Graphics and Virtual Reality DOI: http://dx.doi.org/10.5772/intechopen.102744*

As **Figure 10** proves, models are build up the way just to represent its necessary shapes, to figure out meaning of the object. Disadvantage of low polygon objects is that neglected folds result in a non-realistic look. But it still keeps the shape to figure out the context. One of the advantages is, that this type of modeling practice does not require creating lots of details—LOD for every object. LOD is also an unnecessary feature in wheelchair simulators as scenes are not that wide for LOD to be applied. It is possible to decimate some polygons on a wheelchair or the car model, for example, those parts of model that are not so visible by a user. But a number of polygons will not change dramatically if it is desired to keep the look so it is an unnecessary step. Such a step would be worth considering if these objects were placed into environment multiple times. Then the polygon reduced will be the number of reduced polygons times the number of duplicated models.
