Unit 41 Assignment One Eleanor Kimber



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3D Modeling

Unit 41
Assignment One

Eleanor Kimber
3D modeling is the process of developing a representation of any three-dimensional surface of object (either inanimate or living) in specialized software. The product is called a 3D model. It can be displayed as a two-dimensional image through a process called 3D rendering or used in a computer simulation.



Contents

Applications of 3D






Displaying 3D Polygon Shapes




Geometric Theory




Mesh Construction

3D Development Software

Constraints





http://www.techimo.com/images/img2/blender3d/modelling_lg.png

3D Models

3D models represent a 3D object using a collection of points in 3D space, connected by different geometric entities such as triangles, lines and curved surfaces.

3D models are widely used anywhere in 3D graphics. Their use predates the widespread use of 3D graphics on personal computers. Many computer games used pre-rendered images of 3D models.

Today, 3D models are used in a wide variety. The medical industry uses detailed models of organs. The movie industry uses them as characters and objects for animated and real-life motion pictures. The video game industry uses them as assets for computer and video games. The science sector uses them as highly detailed models of chemical compounds. The architecture industry uses them to demonstrate proposed buildings and landscapes through Software Architectural Models. Engineering uses them as designs of new devices, vehicles and structures as well as a host of other uses.



Applications of 3D.

3D models are split in two separate categories, Solid and Shell/boundary’s. Solid models are the most realistic and define the volume/weight of an object they are supposed to represent. They’re more difficult to develop within a software package. An example of solid modelling would be ornaments.

Product design: Product design involves the designers of a product gathering and suggesting designs that would suit the intended audience of the product, for example they may have a meeting and brainstorm to develop new or flesh out existing ideas on the subject. Eventually the designers will start to create the product, several designers may be working on the same product or there may be several designers creating different products to better decide on which is the first choice.

There are several ways a designer will create an object, the most popular being Autodesk and adobe software’s, these include Autodesk’s own CAD package and many adobe packages like Bridges and Photoshop. They may also use other programs like 3ds max, which is another software package from Autodesk. This editing software allows the user to create and develop 3d objects and make them anything they can think; this is very useful to designers. The developer would also talk to the designers about how the product is specific to a certain age range; for example a 3+ videogame would not work with massive amounts of horrific monsters stained in blood, the designers would have to develop child friendly characters.

Animation, TV, Film and Videogames: These are the main users of 3d technology, animation is the main user of 3d as modern animations like cartoons use the tools necessary to develop a piece of 3d entertainment; it is the same with videogames and some TV shows that are animated and not shot in real 3d like Eastenders. Films are different, the producer developing a cartoon film like Toy Story will use 3d development software heavily whereas someone who is developing a film that uses CGI characters as well as real people will use a mix of real filming and software, possibly using green screen as well. A prime example of a CGI film is Transformers; some sections are real film whereas other parts use CGI to mix the giant robots with the real actors http://preview.turbosquid.com/preview/2013/08/04__04_58_52/11.jpg07e63bfa-4114-46d2-a9b5-21d8341b9286large.jpghttp://preview.turbosquid.com/preview/2012/02/04__14_41_03/untitled-2%20copy.jpg2f9ef905-4c7e-4866-9b58-beb239f49842large.jpg

3D modelers allow users to create and alter models via their 3D mesh. Users can add, subtract, stretch and otherwise change the mesh to their desire. Models can be viewed from a variety of angles, usually simultaneously. Models can be rotated and the view can be zoomed in and out.



Displaying 3D Polygon Shapes

In 3D computer graphics, polygonal modeling is an approach for modeling objects by representing or approximating their surfaces using polygons. Polygonal modeling is well suited to scan line rendering and is therefore the method of choice for real-time computer graphics. Alternate methods of representing 3D objects includesubdivision surfaces, and equation-based representations used in ray tracers.

The basic object used in mesh modeling is a vertex, a point in three dimensional space. Two vertices connected by a straight line become an edge. Three vertices, connected to each other by three edges, define a triangle, which is the simplest polygon. More complex polygons can be created out of multiple triangles, or as a single object with more than 3 vertices. Four sided polygons and triangles are the most common shapes used in polygonal modeling. Each of the polygons making up an element is called a face.http://www.imanishi.com/mayablog/mayapolygon/pa1.jpg



Rendering Technologies
The two major manufacturers in the graphics card world are ATI and nVidia. These companies have developed their own rendering technologies to process graphical data. nVidia uses CUDA Cores and ATI uses ATI Stream technology. While these technologies are measured differently, their purpose is to accelerate the communication rate between the graphics card GPU and your computer's CPU. Look for a card that has higher numbers of CUDA Cores or ATI Stream capabilities. The higher the number the faster your video card will be, and this makes your program or game run smoother and faster. ATI and NVidia have also made great strides in the graphic world integrating real world physics and offering 3D capabilities.

Direct 3D and OpenGL

Direct3D and OpenGL are competing application programming interfaces (APIs) which can be used in applications to render 2D and 3D computer graphics, In general, Direct3D is designed to imitate 3D hardware interfaces. Direct3D frees the game programmer from accommodating the graphics hardware. OpenGL, on the other hand, is designed to be a 3D hardware-accelerated rendering system that may be emulated in software. These two APIs have been designed under two separate thoughts.

Direct 3D is a part of Microsoft Direct X software it is used from 32d graphics render on all windows OS and can also be used on the Xbox consoles. Direct 3D allows for a full screen viewing so that you can see everything on the screen at one time, alpha blending and texture mapping making it a excellent assiting to the Microsoft software

While OpenGL is a cross platform rendering software for oth the 3D and 2D graphics, it interacts with the GPU to produce a quicker graphic rendering overall making the process move a lot quicker then Direct3D

Graphics Cardshttp://images.bit-tech.net/news_images/2009/01/palit-launches-the-first-55nm-custom-designed-nvidia-graphics-card-palit-gtx260-sonic-216sp/palit_gtx260_sonic_216sp_01.jpg

If we look at the latest verison of grahpics card which is the GeForce GTX 780 Ti is a top-end discrete graphics card for desktop computer systems, NVIDIA built the GeForce GTX 780 Ti specifically for high-performance hardware enthusiasts and hard-core gamers. In compareison to the GeForce 8400 GS 512MB It's silent and cheaper than the GeForce GTX 780 Ti. The DVI port is HDCP enabled, making the card a strong choice for a media-centre PC. Just don't expect to do any great gaming.



So why do we need a good graphics card for 3D Modeling well they can make a big difference, as they affect what you see on screen and how fast that view updates, along with things like real-time shadow quality in rendered mode and anti-aliasing quality of lines and edges. If you work with very simple models, a better card may not feel very different than a cheaper card, but the more you are displaying on your screen at once, the better of a card you'll want. It can be the difference between a slick, smooth experience, and a jerky performance.

Rendering can take a considerable amount of time on any computer this is why if you get a better graphics card the less time it will take compared to the cheaper lower scale cards. If a model is very complex it can take many hours to render out the whole mesh or if you have created an animation it may take longer as each frame has to be processed one at a time.

Lighting and Shadows.

Light and shadow are huge parts of are general life they allow us to see our world. Creating realistic simulations of them on 3D Studio max can be quite challenging. Lighting calculates the effect of a light source of a model this can include reflections and shading. The light source can determine how the scene will render in terms of colour without any light your scene will be black.

During rasterization the colours and textures are assigned to the model that you have created as well as the lighting effects the area this shall determine how the final model will look when it is fully rasterized

By default, 3D Studio Max will use an ambient light to light the scene. The thing is the chances of this light being exactly the light you want for your scene are very small. So, the first things you could to do is add some lights working with omni lights give your scene a natural look. While when you're using something like a spot, you'll get a hotspot and a falloff zone, which you don't have in real life. Omni's make your light scatter nicely.

Applying Materials to a Shapeapply multiple=

Once you have 3D Studio max open you need to create the object you wish to add materials to then select your object, while still selected, right click the box and convert the object to an Editable Poly. After this click the Modify tab, click the Polygon icon and select a single face. Now click the Create tab to exit the sub-object level, hit the “M” key to access the Material Editor and select the first empty material. Click the Standard button next to the material’s name and assign a Multi/Sub-Object material. Then assign the material you wish you use and just like magic it appears on your object.

Geometric Theory

The basic object used in mesh modeling is a vertex, a point in three dimensional space. Two vertices connected by a straight line become an edge. Three vertices, connected to each other by three edges, define a triangle, which is the simplest polygon. More complex polygons can be created out of multiple triangles, or as a single object with more than 3 vertices. Four sided polygons and triangles are the most common shapes used in modeling. A group of polygons, connected to each other by shared vertices, is generally referred to as an element. Each of the polygons making up an element is called a face.

http://moderndynamics.files.wordpress.com/2012/09/elements-of-mesh-modelling.png http://s.cghub.com/files/image/638001-639000/638473/045_max.jpg

Wireframe and Realistic Views

A wire frame model shows three dimensional or physical object used in 3D computer graphics. It's created by specifying each edge of the physical object where two continuous smooth surfaces meet. Using a wire frame model allows visualization of the underlying design structure of a 3D model.

While realistic view model shows you what your item/object will look without all the lines it will have smooth surfaces and will like just as how you would see it in the real world.

Box Modeling is a technique developed to create complex models from simple starters creating a rough shape of a model and the refining it to how you want it to look. The model usually starts as a basic primitive shape such as a cube or a sphere and is then expanded to make into the model you desire.

Extrusion Modeling is where the mesh of the object you have created is extruded into different form extrusion can be used to collapse or expand surfaces this is most commonly used in creating simple cubic models

3D development software

Autodesk 3ds Max, formerly 3D Studio Max, is a 3D computer graphics program for making 3D animations, models, and images. It was developed and produced by Autodesk Media and Entertainment. It has modeling capabilities and can be used on the Microsoft Windows platform. It is frequently used by video game developers, many TV commercial studios and architectural visualization studios.

Autodesk Maya shortened to Maya, is 3D computer graphics software that runs on Windows, Mac OS and Linux, originally developed by Alias Systems Corporation but is now owned and developed by Autodesk, Inc. It is used to create interactive 3D applications, including video games and animated film.

LightWave 3D is a 3D computer graphics software program developed by NewTek. LightWave has won more Emmy Awards than any other 3D application on the market at the moment.

AutoCAD is a software application for 2D and 3D computer-aided design (CAD) and drafting. Developed and marketed by Autodesk, Inc. AutoCAD was first released in December 1982. The software is currently marketed in its eighteenth generation. AutoCAD is used across a range of industries, including architects, project managers and engineers.

file:autodesk maya 2013 sp2 extension x64 on win8.png

File Formats

.3ds= Is one of the oldest forms of 3D file format. 3ds is now a common way of transferring models between programs as it is compatible with a lot of graphics software.

.mb= mb is a very basic format of coding that creates a base for mesh work it is most commomly used with corel paradox.

.blend= blend is a file formate created by Blender Software and is only compatible with Blender itself but can be very easily converted into other formats

.dxf= dxf is a universal file type developed by CAD allowing a large range of applications to access auto CAD files. This file type is very adaptable and also quite assessible as almost any 3D software can open it.

Constraints

Polygon Count = A computer or a laptop it limited as to how muh it can take of the 3D Modeling programe based on how high tech the computer system is, computer systems often have to be upgraded to be able to meet the ever improving graphics as the expand over time. The reason for this is the polygon count it can be very computer intensive when it reaches a high amount so sometimes the system will crash or freeze.

Rendering Time = As I have spoke about before in this report rendering can sometimes take a very long time on a computer if a model is highly complex.

File Size = This can be a big problem to dealing with the complexity of some meshes, the often have to be optimized to provide the bare minimum file size but then this could lead to a loss of the quality.

Export Platform = When a 3D Model is created it may not be compatible with where it is desgined to be used for. For example a too complex model would have a very large data comsumption therefore it would need to be simplyfied

References

http://kieffmoon.wordpress.com/unit-66/applications-of-3d/


http://scotty1108.wordpress.com/3d/applications-of-3d/

http://en.wikipedia.org/wiki/3D_modeling

http://en.wikipedia.org/wiki/Comparison_of_OpenGL_and_Direct3D

http://www.the3dstudio.com/product_details.aspx?id_product=587320

http://maxschmer3d.blogspot.co.uk/2012/09/ritgar-rraz.html

http://www.cgrats.com/apply-multiple-materials-to-an-object.html



http://www.bit-tech.net/news/industry/2009/01/23/palit-launches-the-first-55nm-custom-designed-nvidia-graphics-card-palit-gtx260-sonic-216sp/1

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