In 3D computer graphics, 3D modeling (or three-dimensional modeling ) is the process of developing a mathematical representation of every surface of an object (either non-live or live) in three dimensions through specialized software. This product is called 3D model . Someone who works with a 3D model can be called a 3D artist . It can be displayed as a two-dimensional image through a process called 3D rendering or used in computer simulations of physical phenomena. This model can also be made physically using a 3D printing device.
Models can be created automatically or manually. The manual modeling process for preparing geometric data for 3D computer graphics is similar to plastic art such as sculpting.
3D modeling software is a class of 3D graphics computer software used to produce 3D models. This individual class program is called modeling app or modeler .
Video 3D modeling
Model
The three-dimensional (3D) model represents the physical body using a collection of points in 3D space, connected by various geometric entities such as triangles, lines, curved surfaces, etc. Being a data set (points and other information), 3D models can be created by hand, algorithmically (procedural modeling), or scanned. Their surface can be more determined by texture mapping.
3D models are widely used anywhere in 3D and CAD graphics. Its use precedes the widespread use of 3D graphics on personal computers. Many computer games use 3D model images that were previously created as sprites before the computer can render them in real-time. The designer can view models in different directions and views, this can help designers see if objects are created as intended to be compared to their original vision. Viewing the design in this way can help the designer/company know the changes or improvements required for the product.
Currently, 3D models are used in various fields. The medical industry uses detailed organ models; this can be made with several pieces of 2-D images from MRI or CT scan. The film industry uses them as characters and objects for animated and real-life movies. The video game industry uses it as an asset for computers and video games. The science sector uses them as a very detailed model of chemical compounds. The architectural industry uses it to show the proposed buildings and landscapes as a substitute for traditional physical architecture models. The engineering community uses them as the design of new devices, vehicles and structures as well as a number of other uses. In recent decades the Earth science community has begun to build 3D geological models as standard practice. 3D models can also be the basis for physical devices built with 3D printers or CNC machines.
Representation
Almost all 3D models can be divided into two categories.
- Solid - This model specifies the volume of the object it represents (like a rock). Solid models are mostly used for medical techniques and simulations, and are usually built with constructive solid geometry
- Shell/boundary - this model represents the surface, e.g. limit the object, not the volume (like a very thin eggshell). Almost all visual models used in games and movies are shell models.
Solid and shell modeling can create functionally identical objects. The differences between them are largely variations in the way they are created and edited and the conventions of use in different fields and the different types of estimates between models and reality.
Shell models should vary (do not have holes or cracks in the shell) to be meaningful as real objects. A polygonal mesh (and on a lower subdivision surface) is by far the most common representation. Set level is a useful representation for deformation surfaces that undergo many topological changes such as fluid.
The transformation process of object representation, such as the sphere point of the sphere coordinate and the point on its perimeter into a spherical polygon representation, is called tessellation. This step is used in polygon-based rendering, where objects are broken down from abstract representations ("primitives") such as spheres, cones etc., for so-called snares , which are the nets of interconnected triangles.. Citrus triangles (not squares) are very popular because they have proven easy to rasterise (the surface described by each triangle is planar, so the projection is always convex);. Polygon representation is not used in all rendering techniques, and in this case the tessellation step is not included in the transition from an abstract representation to a given scene.
Maps 3D modeling
Modeling process
There are three popular ways to represent a model:
- Polygononal Modeling - Points in 3D space, called nodes , connected by line segments to form polygon mesh. Most current 3D models are built as textured polygonal models, because they are flexible and because computers can make it so fast. However, polygons are planar and can only approach curved surfaces using many polygons.
- Curve modeling - The surface is determined by the curve, which is affected by the weighted control point. The curve follows (but does not need interpolation) points. Increasing the weight for a point will draw the curve closer to that point. Curve types include non-uniform rational B-splines (NURBS), splines, patches, and geometric primitives
- Digital sculpting - Still a fairly new modeling method, 3D sculpting has become very popular in recent years. There are currently three types of digital sculpting: Displacement, the most widely used among the current applications, uses a solid model (often generated by the subdivision surface of a polygon control mesh) and stores a new location for the vertex position through the use of an image map that stores a customized location. Volumetric, loosely based on voxels, have the same ability as displacement but do not suffer from stretching polygons when there are not enough polygons in an area to achieve deformation. Dynamic tessellation is similar to voxel but divides the surface using triangulation to keep the surface smooth and allows finer detail. These methods allow for very artistic explorations because the model will have a new topology created on it once the model is formed and perhaps the detail has been sculpted. The new mesh usually has the original high-resolution mesh information transferred to the moving data or normal map data if for a gaming machine.
The modeling stage consists of forming individual objects which are then used in the scene. There are a number of modeling techniques, including:
- Constructive solid geometry
- Implicit surface
- Subdivision surface
Modeling can be done using a special program (eg, Cinema 4D, Maya, 3ds Max, Blender, LightWave, Modo) or application components (Shaper, Lofter in 3ds Max) or some scene description language (as in POV-Ray). In some cases, there is no clear distinction between these phases; in such cases modeling is only part of the scene-making process (this is the case, for example, with Caligari trueSpace and Realsoft 3D).
Complex materials such as gravels, clouds, and liquid sprays are modeled with particle systems, and are 3D coordinate masses that have dots, polygons, textures, or sprites assigned to them.
Human model
The first commercial application of the virtual human model appeared in 1998 on the Lands' End website. The virtual human model was created by My Virtual Mode Inc. company. and allows users to create models themselves and try out 3D outfits. There are several modern programs that allow the creation of virtual human models (Poser being one example).
3D Outfit
The development of fabric-simulation software such as Marvelous Designer, CLO3D and Optitex, has enabled fashion artists and designers to model dynamic 3D clothing on computers. Dynamic 3D outfits are used for virtual fashion catalogs, as well as to match 3D characters for video games, 3D animated movies, for digital doubles in movies and to create clothing for avatars in a virtual world like SecondLife.
Compared to 2D method
3D photorealistic effects are often achieved without wireframe modeling and are sometimes indistinguishable in final form. Some graphic art software includes filters that can be applied to 2D vector graphics or 2D raster graphics on transparent layers.
The advantages of 3D wireframe modeling over 2D methods exclusively include:
- Flexibility, the ability to change angles or animate images with faster change rendering;
- Ease of rendering, automatic counting and rendering of photorealistic effects rather than mental or approximate visualizations;
- accurate Photorealism, less chance of human error in placement, overload, or forgetting to include visual effects.
Disadvantages compared to 2D photorealistic rendering may include software learning curve and the difficulty of achieving certain photorealistic effects. Some photorealistic effects can be achieved with special render filters included in 3D modeling software. For the best of both worlds, some artists use a combination of 3D modeling followed by editing 2D computer-generated images from 3D models.
3D model market
Great markets for 3D models (as well as 3D-related content, such as textures, scripts, etc.) are still there - whether for individual models or large collections. Some online markets for 3D content allow individual artists to sell content they have created, including TurboSquid, CGStudio, CreativeMarket Sketchfab, and CGTrader. Often, the artist's goal is to get additional value from the assets they have previously made for the project. That way, artists can make more money from their old content, and companies can save money by purchasing ready-made models, instead of paying employees to make them from scratch. These markets typically divide sales between themselves and the artist who creates the asset, the artist gets 40% to 95% of sales according to the market. In many cases, the artist retains ownership of the 3d model; the customer simply purchases the right to use and present the model. Some artists sell their products directly in their own stores offering their products at lower prices by not using intermediaries.
Over the last few years many specialized markets in 3D printing models have emerged. Some 3D printing markets are a combination of model sharing sites, with or without e-com capabilities built. Some of these platforms also offer 3D on demand printing services, software for model creation and dynamic display of items, etc. The 3D printing file printing platform includes Shapeways, Sketchfab, Pinshape, Thingiverse, TurboSquid, CGTrader, Ukrafty Threeding, MyMiniFactory, and GrabCAD.
3D Printing
3D printing is a form of additive manufacturing technology in which a three-dimensional object is created by laying or constructing of a sequential material layer.
Printing 3D is a great way to create objects because you can create objects that you can not create in other ways without making expensive complicated prints or by creating objects created with multiple sections. 3D printed sections can be edited only by editing 3D models. That avoids having to do additional tools that can save time and money. 3D printing is great for testing ideas without having to go through an excellent production process to get the physical shape of a person/company idea
In recent years, there has been an increase in the number of companies offering personalized 3D print object models that have been scanned, designed in CAD software, and then printed as per customer requirements. As mentioned earlier, 3D models can be purchased from the online market and printed by individuals or companies using commercially available 3D printers, enabling the production of home goods such as spare parts, mathematical models, and even medical equipment.
Usage
3D modeling is used in industries such as film, animation and games, interior design and architecture. They are also used in the medical industry for interactive anatomical representation. A large number of 3D software are also used in building digital representations of models or mechanical parts before they are actually made. CAD/CAM related software is used in such areas, and with this software you can not only build parts, but also collect them, and observe their functions.
3D modeling is also used in the field of Industrial Design, where 3D products are modeled before representing them to clients. In the Media and Events industry, 3D modeling is used in Stage Design/Set.
The OWL 2 translation of the X3D vocabulary can be used to provide semantic descriptions for 3D models, suitable for indexing and retrieving 3D models with features such as geometry, dimensions, materials, textures, diffuse reflections, transmission spectra, transparency, reflectivity, opalescence, glazes, varnishes , and enamel (as opposed to an unstructured textual description or 2.5D virtual museum and exhibit using Google Street View in Google Arts & Culture, for example). The 3D model RDF representation can be used in reasoning, which enables smart 3D applications that, for example, can automatically compare two 3D models by volume.
Test 3D Solid Model
3D Solid models can be tested in various ways depending on what is needed by using simulation, mechanism design, and analysis. If the motor is properly designed and assembled (this can be done differently depending on which 3D modeling program is being used), using the user's mechanism tool should be able to know whether the motor or engine is properly assembled by how it operates. Different designs need to be tested in different ways. As an example; the pool pump will require simulation of the flow of water flowing through the pump to see how water flows through the pump. This test verifies whether a product is developed correctly or if necessary I am modified to meet its requirements.
See also
External links
Media related to 3D modeling on Wikimedia Commons
References
Source of the article : Wikipedia
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