## 4 Results and Analysis
### Results of the Online Questionnaire of Public Space Design Stakeholders  
A total of 102 participants completed the questionnaire on graphic documents and digital graphic expertise (212 participants started but did not finish). The population includes different ages with different (and often combined) functions; A total of 72% are civil servants. The distribution of gender (58.8% male; 36.3% female; 4.9% no response) and age was fairly even; it was found that 19% of participants were younger than 34 years, 63%  
Figure 3: (**a**) Preliminary familiarization with designing in VR; (**b**) the use of VR controllers during designing; (**c**) the use of 3D furnishing objects and the teleportation function; (**d**) the VR bike; (**e**,**f**) detailed and animated VR environment (including soundscape). were between 25 and 54 years old, and 18% were older than 55 years. More important than other parameters was the decision to compare designers' opinions (27 out of 102) with those of non-designers. This is because the public space designers (usually the plan's drafters) have graphic training, whereas all others are citizens or stakeholders (with advisory or decision-making roles) and do not have the same professional training as designers, thus having less knowledge about graphic techniques. Figure 4a shows how designers and non-designers feel about using 2D, 3D, and 4D (3D with the addition of animation or changes over time) during the design process. About half of all participants thought that 3D techniques should be used whenever possible. Strikingly, almost half of the designers still advocated a design process in 2D (and that 3D should only be used for communication), while only a third of non-designers shared this opinion. Therefore, the desire for 3D is greater among non-designers than among designers, although a third of all participants considered 3D unnecessary because 2D was considered to provide sufficiently accurate impressions. A minority of less than 15% of all respondents  
Figure 4: (**a**) Participants’ use of 3D during the design process; (**b**) experience with VR glasses; (**c**) experience with AR glasses; (**d**) experience with a 3D CAVE. The use of 2D/3D in participation. considered 3D to be too complicated, too expensive, and too tedious. It is striking that designers were more critical than non-designers. Twenty-two percent of designers believed that 3D should only be used for large projects. A quarter of designers (and almost a third of non-designers) thought that 4D should be used. In summary, there were no essential differences between designers and non-designers; about half of both groups always wanted 3D representations. Most importantly, about a third of all participants believed that using 3D improved the design quality. Nevertheless, some of the designers were still convinced that designing in 2D was the better option. It was found that 46% of the non-designers and 41% of the designers believed that the whole design process would be in 3D within five years; designers were the most pessimistic, with 26% believing that this would not be the case for 20 years or more. Concerning XR interfaces, less than 35% of participants used VR glasses more than once and less than 15% used AR applications or 3D CAVEs (Figure 4b-d). Notably, the group of designers scored 5% lower each time. Concerning participation, appreciation for deploying 2D, 3D, VR, and AR systems were polled (Figure 5). Only an extreme minority thought that limited or no public participation was necessary. One fifth of non-designers valued participation by drawing on paper, while just over a third of designers found this to be sufficient. It is notable, however, that 10% more designers compared with non-designers found 2D plans to be sufficient in participation workshops. When using 2D co-design, there was no difference in appreciation between designers and non-designers; it was only a minority, and there was little enthusiasm for 2D.