There are different ways of creating textures for 3D objects. One of these is procedural texturing, which uses an algorithm to create a realistic representation of natural elements, e.g. wood, stone, metal and marble. The other, well-known and widely used method is UV mapping. UV mapping is the breakdown of the shape of the object into a 'net', an open, spread out flat surface ready to paint a texture onto. A design can then be drawn onto the UV map using programs such as Photoshop, then re-applied to the shape to create a texture. This adds realism to the object and is very effective in terms of aesthetics when used with lighting.
Mesh Construction:
To create a mesh of a shape there is a variety of tools available on 3D modeling programs which provide an alternative to just specifying vertices and faces. For example, box modeling can be used, which is done by two different tools: 'subdivide' or 'tesselate' can split a face by adding extra vertices and connecting them with lines, therefore making them into smaller shapes (for example, a square could be split into four using lines crossing the centre of the square horizontally and vertically, with new vertices in the centre and around the edges of the square).
The extrude tool can then be used to draw shapes out from the faces of the original vertex shapes.
Extrusion modeling can be used by creating a 2D shape that traces the outline of an image of photograph at one angle, then using a second image at a different angle to extrude the shape into 3D, made to fit the shape of both images. This method is used mostly to create heads and faces.
Another method of mesh construction is the use of common primitives, using tools such as 3D Boolean to either add the shapes together or subtract one from another and leaving the rest as the resulting shape.
3D Development Software:
Software:-
Nowadays there is a wide variety of 3D software that is accessable by almost anyone and is used by both amateur designers and companies and in industry in general. Each program is different in terms of tools, resulting render aesthetic and approaches to object creation.
The most popular programs are Carrara, 3D Studio Max and Maya.
Eovia Carrara is the most basic of the programs, using simplistic approaches to creation and rendering of objects and scenery. This means that the render result quality isn't the highest, but is fairly quick in rendering time compared to the others.
Autodesk Maya is one of the most popular of the programs, used widely in industry and in higher education. It is well-known for its high-quality renders and smooth animation, and uses a polygon-based system as well as NURBS (a type of spline) and Subdivision surfaces to model with. The program even includes a particle system, allowing natural movement to be used to create realistic scenes. The precise and professional quality of the renders means that rendering would take a lot more time than a program such as Carrara, and the file sizes would be a lot larger, which in turn takes up space a lot quicker. To combat this, professional companies have larger servers with higher processors which means renders will be done quicker, and there would be plenty of space on the hard drive for the files.
3D Studio Max (3DS Max), also by Autodesk, is slightly similar to Maya with its high-quality renders, but has additional features such as advanced shaders, particle systems, radiosity, an intuitive and customisable user interface, and even its own scripting language. It is used by film companies for special effects and CGI scenes and characters, as well as in game design. The library of primitive is extensive in comparison to Carrara, which makes modelling from primitives easier, but this wouldn't be a preferred method in this program as polygon-based modeling is the easiest to use.
File Formats:-
File formats are used with different files to indicate the encoding convention of its contents. Most files are linked to a specific program using the file format extension, which automatically opens up the file in that program when double-clicked (or, when right-clicked, can be opened with different porgrams depending on compatibility).
3D file formats will be used when saving whole projects rather than a rendered scene. This allows a user to quickly and efficiently access their work in order to make any changes. This can also include export files, which are file types of the resulting exported files (i.e. Object files)
Types of files associated with 3D graphic production are:
- .car (Carrara)
- .3ds (3DS Max)
- .ma (Maya)
- .lwo (Lightwave Object)
- .obj (Universal 'object' export file type)
- .C4d (Cinema 4D)
- .blend (Blender)
Plug-ins:
A plug-in is a set of software components that allows users to add specific capabilities to a software application. Plug-ins can allow customisation of functions of an application, or allow the use of file types or functions that had not previously been allowed in the original application.
A well-known and widely used example of a plug-in is Java. It is used quite often in accessing videos (e.g. YouTube videos) and online 3D games (e.g. Runescape). It is highly accessible and when a user doesn't have the plug-in installed, there is always an offer to link the user to the website to download the plug-in, or download it directly from the site they are currently using.
Constraints:
Polygon Count:-
When creating 3D models, polygon count is highly important when it comes to quality in final renders. The higher the amount of polygons, the smoother the models will be, and the more aesthetically appealing the final scene will be. In game development, having a balanced polygon count is vital, ensuring that gameplay is smooth and doesn't lag, but also looks good in terms of imagery and visual appeal. Once the polygon count goes too high, the game can lag, moving extremely slowly which slows down or completely halts gameplay. An example of this is the 'duplication' cheat on the game Elder Scrolls IV: Oblivion, by Bethesda Softworks. Once an object or character has been duplicated several times, the polygon count grows too high and the game begins to slow down and stop the user from playing it properly.
File Size:-
File size depends on the resolution of the final rendered scene. The higher the pixel count/resolution of the rendered image, the larger the file. Polygon count will affect the size of the 3D modeling file (such as a .car file), but the render size depends on resolution. This quickly uses up space, so users would need to have a large enough hard drive and internal memory to store all of the files.
Rendering Time:
Once again, rendering time is affected by polygon count. The higher the count in the scene, the longer the render will take, and would need a powerful processor and server to cope with the amount of rendering. This particular problem is where render farms are useful and get the work done more quickly.
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