Interaction forms in VR

interactive and similar to the real word: 1. Audio; 2. Motion (application of motion capture on 3D virtual objects); 3. Touch that allow to touch and feel virtual objects. 4. Taste/Flavor. 5. Smell.

- Extended reality

XR encompasses all the previous 360-degree video, augmented and mixed realities. XR enables real

interaction although objects and virtual environment. XR synchronizes VR and MR by bringing real-time

data to them.

Interaction forms in VR

Interactivity is crucial in the virtual reality. With continual advancement in computer, virtual

environments have the potential to provide a natural form of human-computer interaction in which user

uses his eyes, ears, and hands almost similarly to the real word. Virtual world will perfectly simulate in a

realistic view interactivities from the physical world. The main forms of interaction in virtual environments according to Mine (1995) are gaze interaction, experience (moving/navigating), selection

and manipulation or acting (scaling, transforming).

Figure 94 Interaction forms in VR ( authors interpretation based on Mine (1995))

1. Gaze interaction.

Gaze interaction mean that interaction with things happen only by looking at objects in the environment.

It includes looking around in the virtual environment whether it could be a text, an image, a 3D model or

a moving image based, exploring its content, without being able to manipulate it. The user remains still

while seeing a 360-degree picture. Because there is no reaction to user inputs, this is considered a low

degree of interactivity. In this category of experience engagement, a somewhat greater degree of gaze

interaction may be obtained using real-time sound and tactile feedbacks. The tool use d for navigation is

“360 VR video”, a rotational tool that allows the user to look around.

Advanced gaze interactions include not only passively glancing at the virtual world, but also displaying

desire to pick digital material, handle particular items, or move the cursor by gaze (Lee et al., 2014).

Gazing interaction in this case also involves movement through space and selection of objects.

2. Experience interactivity

Experience interactivity mean to move or to navigate in the virtual environment whether it could be a

text, an image, a 3D model or a moving image based, exploring its content, again without being able to

manipulate it. In virtual space, users can get around in different viewpoints of the scene. In VR, they are

not limited to have real space points of view, but are free to explore the environment through infinite

viewpoint, though having a more comprehensive understanding of space. The process of getting

navigating the environment while recording details of space and activities is tight to an architecture

approach in space relate to rules of wayfinding, viewpoints control and navigation and camera tools. The

virtual environment used for navigation can be both camera-based VR and model-based VR.

Considering both of them, Mackinlay et al. (1990) distinguish four types of viewpoint movement for

interactive virtual environment.

 Movement. Movement to explore space, such as walking through an architecture space, without

any specific goal, flying through the environment or driving by using vehicles. They can include

tools similar to architectural design programs such as: modify camera position through the use of

arrows or mouse control, rotate, zoom, pan, in order to explore and inspect objects in the virtual

environment. Usually movement is viewed from user perspective, which is video game is defined

as first person perspective (FPP).

 Targeted movement. Movement towards a target, to examine it in detail.

 Position movement. Movement to a precise position in the model/ virtual space. Hence, the

viewpoint flies directly to a target which might be a point of interest.

 Trajectory movement. Movement along a specific path as in cinematography or guided

navigation. This technique allow user to project a walking camera through a certain path,

defined or designed by the user providing better views or guided views in order to avoid

disorientation.

3. Transformational Interactivity. Actions: Selection, Manipulation and transformation

Transformational interactivity allows users not only to move and look around the environment but also

to engage with the environment, to perform tasks and to transform it (ex. selecting, moving, opening,

holding, closing, rotating and placing objects).