Table 2.

Glossary: detailed description of the technical terms used in the text

2D/3D computer animation	Computer animation describes the process of generating animated images (frames), concatenated to videos. In contrast to 3D computer animations, 2D animations are based on a 2D geometry and do not take depth perception into account. Typical examples of 2D computer animations are cartoons. The 3D animations are more complex and more realistic and based on a 3D geometry. With these it is possible to create depth perception for the observer.
Bones (animation)	Within the context of computer animation a bone is a structure inside a model mesh similar to a bone inside a human body. It is connected to the surrounded 3D model mesh. All transformations and rotations of the bone directly affect the connected polygon mesh regarding the predefined weight (→ weight painting). With these it is possible to move whole mesh groups like an arm of a human by just moving 1 bone.
Cage transform	Special editing tool in GIMP. With this, the user can select an area of an image and can push or pull the borders of this selection to deform it.
Computer vision	Computer vision covers the field of automatic processing, analyzing, and understanding camera images with help of a computer.
Frame (video)	In context of video and animation, a frame is a single image within the sequence of moving images of a video or animation.
Frame rate (fps)	Indicates the number of displayed images (→ frames) within a sequence of images of a video or animation per second.
Game engine	A game engine is a software framework for computer game development. In general, it provides tools for game design, development, and execution. During execution it renders (draws) the 3D virtual scene on screen.
Generic stimulus model	A generic stimulus model is a generalization of a fish stimulus. It can be configured regarding size, morphology, and texture to generate a unique new stimulus of the used species.
Graphical user interface (GUI)	A GUI is a screen-based control panel to interact with the computer. The information on the computer is visualized with graphical elements. The user can select these elements to control the computer. A classical GUI is, for example, controlled with the help of a computer mouse.
Human machine interface (HMI)	A HMI enables human to interact with computers. With this, a human operator can control machines, whereas the machine sends feedback back to the operator. Examples of HMI are GUI command line interfaces or web-based interfaces.
Image editing tool	With the help of image editing tools the user can manipulate digital images. For example, it enables the user to resize, recolor, crop, or retouch images. For a useful list, see Chouinard-Thuly et al. (2017).
Interactive computer animation	In contrast to classical computer animations, interactive computer animations are generated in real time and can react or respond to input signals.
Key-frame animation	A method to animate objects or models. The user defines object parameters like position or orientation at a certain time and the computer calculates and generates the frames between these “key-frames”. This method reduces the effort of the animator as he do not have to define every frame of an animation but just significant positions.
Manipulator (robotics)	Mechanical device that enables robots to interact physically with the environment.
Mesh (polygon)	A polygon mesh represents the surface of a 3D object. It consists of edges and vertices, connected to a kind of net.
Middleware	A middleware is a software that is located between the computer operation system and the application or service. It provides several tools, which simplifies the development process of applications.
Motion capture	Process of analyzing and recording the movement of objects, animals, or humans.
Node	A node is a software application within the middleware ROS (→ middleware, → ROS).
Open source (software)	The programming source code of open-source software is free available and can be modified by the user. In contrast, closed software can just be used but not reprogrammed.
Polynomial spline interpolation	Mathematical approach to approximate a mathematical function with the help of piecewise polynoms (splines) out of predefined points.
Presentation software	Presentation software is used to create graphical presentations and to present these presentations to the audience.
Rendering	Rendering is the process of converting virtual 3D models or whole 3D scenes to a 2D image. This is necessary to display the object or scene on a 2D screen. Prerendering: Since the rendering process can be very computationally intensive and consequently very time-consuming, the images are rendered time-independent and stored in a video file. The final video can be played faster so that the animation runs fluently. Real-time rendering: In contrast to prerendering, real-time rendering has the possibility to modify the animation during runtime. It is used for computer games or applications where the animation depends on input parameters. In general, real-time rendered animations are not that complex, so that it can be rendered faster.
ROS	Middleware (→ middleware) for robotic purpose. It provides several tools and features, helping developers to program and execute software for robots. In addition to its application in the field of robotics it also has a lot of benefits for all areas of application, where sensors (e.g., cameras) are included or software applications are distributed to multiple computers and a network communication is necessary.
Rotoscoping (animation)	Method to animate objects or models. It describes the process of deriving the movement of an object from a video by adjusting the virtual counterpart manually frame by frame so that the overlay of the animation is congruent with the object video.
Screen-based stimulus	A stimulus, which is shown on screen.
Semi-automated steering	Describes a steering mode, which is mostly automated but still needs user input. This mode lightens the user’s workload.
Sensor	Device, which detect or analyzes some type of input from the physical environment. The input can be, for example, light, sound, or temperature.
Texture (animation)	In animation context, texture means an image, which is mapped to the 3D object or model surface.
Toolchain (software)	A toolchain is a set of software tools to perform a specific task. Every single tool of the toolchain can be used to solve a specific problem. The output of 1 tool is normally the input of the following tool, so that the tools are functionally connected like a chain.
Tracking (video)	Video tracking is a method to locate a moving object over time (frame by frame) in a video sequence. This can be done in 2D and 3D space. In case of 3D tracking, the tracking system calculates the 3D position of the object and—if required—the 3D orientation.
UV mapping	UV mapping describes the process of mapping a texture to a surface of a 3D object. To place a 2D texture to a 3D surface, the 3D object surface gets unfolded to a 2D plan. Since x, y, and z are already used to describe the axes of the 3D object space U and V are introduced to describe the 2D coordinates on the unfolded object surface. The texture position regarding the surface plan is defined in U and V coordinates.
Video editing tool	With the help of a video editing tool the user can manipulate video sequences. For example, it enables the user to cut videos, change coloration, or add subtitles.
Video game controller	A hand-held input device to control, for example, video games.
Weight painting (animation)	Describes the process of connecting the object mesh with the object bones. Since not all parts of the mesh should move regarding a specific object bone in the same way, the designer can use the weight painting function to define the relative bone influence to the related polygon mesh.