A metavers environment is only an abstract multimedia construct and has nothing to do with the RL architecture
A scene graph is a general data structure commonly used by vector-based graphics editing applications and modern computer games. A scene graph is a collection of nodes in a graph or tree structure.
The Node (In SL a prim or agent)
A node may have many children but often only a single parent, with the effect of a parent apparent to all its child nodes; an operation applied to a group automatically propagates its effect to all of its members. In many programs, associating a geometrical transformation matrix at each group level and concatenating such matrices together is an efficient and natural way to process such operations. A common feature, for instance, is the ability to group related shapes/objects into a compound object which can then be moved, transformed, selected, etc. as easily as a single object.
All components in a metaverse environment are nodes with embedded informations as: geometric parameters, textures, scripts etc. In the metaverse infrastructure the scenegraph is divided to 2 parts:
1. server side scene graph
2. client side scene graph
the shared scenegraphs are communicate throu the internet.
Traversals are the key to the power of applying operations to scene graphs. A traversal generally consists of starting at some arbitrary node (often the root of the scene graph), applying the operation(s) (often the updating and rendering operations are applied one after the other), and recursively moving down the scene graph(tree) to the child nodes, until a leaf node is reached. At this point many scene graphs then traverse back up the tree, possibly applying a similar operation.
The server side resources
sim ccordinate system
prim and agent ID
prim and agent pivot position and orientation
event communication with the clients
The client side scenegraph and rendering resources
The culling mechanism
Occlusion Culling is a technique in 3D computer graphics to hidden objects in the scene to determine. The hidden polygons must also not be further treated and painted, which is the speed of calculations for the entire scene increases.
The clipping plane (hide all objects behind the avatar camera)
The viewcone culling (hide all objects out of the camera viewcone)
The viewdistance culling (hide all objects out of the viewdistance)
The 100% transparency (hide all objects with 100% transparency)
The pixel/object culling (hide all objects they smaller in the screen projection as 4 pixel)
The rendering quality (transparency)
The collision detection
In computational geometry, collision detection involves algorithms for checking for collision, i.e. intersection, of two given solids. Simulating what happens once a collision is detected is sometimes referred to as “collision response”, for which see physics engine and ragdoll physics. Collision detection algorithms are a basic component of 3D video games. Without them, characters could go through walls and other obstacles. (use more phantom prim)
The main components in the metaverse environment for the client orientation and interaction.
The client side graphical construct
Rendering is the process of generating an image from a model, by means of computer programs. The model is a description of three dimensional objects in a strictly defined language or data structure. It would contain geometry, viewpoint, texture, lighting, and shading information.
The orientation and interpretation in the graphical construct
The cognitive interpretation
(dont forget: behind all avatar is a bioavatar) Cognitive Science is a relatively young branch of science, whose goal is to investigate cognitive abilities. These skills are about perception, thinking, learning, motor skills and language are counted.
The abstraction and interpretation of a graphical construct:
Ikon style construct: represents the Similarity to RL objects,(imitation)
Symbol style construct: represents the abstract idea.
Recommended the use of the laws of the human visual cognition (perception)
Law of proximity
Law of the unity
Law of similarity
Law of the experience
Differentiation figure / ground
The interaction interface
The Control in the cyberspace. Cybernetics is preeminent when the system under scrutiny is involved in a closed signal loop, where action by the system in an environment causes some change in the environment and that change is manifest to the system via information/feedback that causes changes in the way the system then behaves. This “circular causal” relationship is necessary and sufficient for a cybernetic perspective.
The communication interface
Communication is commonly defined as the imparting or interchange of thoughts, opinions, or information by speech, writing, or signs…, a process by which information is exchanged between individuals through a common system of symbols, signs, or behavior.
The avatar measurements (how great is an avatar?)
a standard generated avatar is aproximately 0.7m x 3m x 2.0m