Unit 66: 3D Modelling
Unit 67: 3D Animation
Unit 68: Enviroments
Start date: 27/09/2016
Deadline: 12/10/2016
Tutor: James Tedder
Student: Shay Wragg
Understanding Theory and application of 3D
What is 3D modelling?
3D modelling is essentially a three-dimensional blueprint. 3D models can be anything from an inanimate object to a human or an animal, it can be used to create art, models for video games or even to create architectural plans.
What is it used for?
3D modelling is used for many things, some of these things are:
- Film - Any animated character, unrealistic setting, extremely large crowds are created using 3D modelling software. if it costs an extensive amount of money to shoot or impossible to shoot directors could shoot the scene as normal and later add a backdrop or change the size of the actor using 3D modelling software. Some films are almost entirely made using 3D modelling. A good example would be iron man, Robert Downey Jr wouldn't actually wear an Iron Man suit, he would wear motion capture gear that would capture the scene and project it onto a screen as a wire frame model, then the suit would be edited on to his model.
- Animation - Animation is used in games and films, when a character is to do any movement in a game it is animated. Where as in a film it could be an explosion or an unrealistic scene that could need animating. Animation consists of many freeze frames, freeze frames are a 3D model positioned in each steps of a movement and when the animation is played the model will do the said movement. For example, to make a model walk you'd have to re position the legs and feet into having one foot in front of the other and then the other foot in front of the previous one and when it's played back the model will be walking.
- Gaming - In every visual aspect of a game 3D modelling is behind it. (As long as the game is 3D that is) whether it's the environment, the weapon you're using or the character itself every single movement and object. The character and weapon models and other objects will be drafted up in development as concepts and if it is accepted then it will be created using 3D modelling software, the model will then have all of their movements animated, whether it's walking, talking, jumping, anything at all it will require an animation. Finally the animation will be coded therefore binding it to a button or key and giving the player control over the model, for example "Move the left stick forward to walk" or "Press A to jump" the model will follow the given instructions and you finally have your playable character.
- Architecture - Traditionally when a building, house or any man made structure is built it all starts with a plan, and the beginning of a plan is a drawing. The drawing is what the architect has in mind initially, it doesn't have to be artistic it just has to tell you what it is that he or she sees. The plan will then be turned into a blueprint and finally the construction workers will follow the blueprint to build the structure. But now days architecture begins with 3D modelling, the structures are built in the software where the client can see the whole structure from any angle they like and can alter it to their liking. Without making a fatal mistake.
- Advertising and Marketing - Companies are always trying to find new products to sell or create new packaging or even find a way to present their product and preferably at a cheaper rate. 3D modellers can create the vision these companies have by simply creating it on a computer rather than spending money hiring camera crews, actors etc. For example car manufacturers, they have to create prototypes, concepts and even logo's etc. A 3D artist can create all three things using 3D modelling software. This will save companies time and money when creating new vehicles/advertising schemes.
- Geology and Science - Scientists are always looking for ways to save lives during natural disasters. They would think of ideas on how to make structures stronger or even deflect things like tornadoes. They would make a 3D model to show the public as well companies or even hold meetings with the people that can provide resources etc.
Building Collapse Study
- Law Enforcement - Police have a new way to find suspects or missing persons. When there is no way of knowing who committed a crime it is possible for the government to take a piece of DNA and analyse it to find what a person look like. For example, in 1984 a murder took place resulting in a small family falling victim, the police had no idea what the murderer looked like but they found DNA not belonging to any of the family members there for could be the killers. Since then technology has progressed and they are able to analyse the DNA and produce a computer generated image of the murder suspect.
Sources:
Geometric Theory and Mesh Construction
In 3D modelling the artist has many tools at their disposal from lines, vertices, faces, primitives etc. A shape can be changed in a number of ways and can be turned into something completely different.
For example in Maya the user can choose from a selection of common primitives such as cubes, spheres, cylinders, cones, pyramids etc. If the user chooses to start from a cube, they can change the edges, faces and vertices by dragging the to a certain position. They could also select the part of the shape they want to move and use tools like the move, rotate or scale tool to change the size and position of the part of their choosing, this is called Box Modelling.
Selection of polygons.
As you can see the user has an array of tools for box modelling, they can edit edges, vertex's (vertices), vertex faces, faces or the whole polygon in object mode.
Move, Rotate and Scale tools
Altering the original shape
There is also subdivisions tool allowing the user to edit multiple parts of one face.
The user can also choose from a selection of angles to look at their work, even multiple at once, the user can also change to wire frame mode to easily edit the outline of a model.
Extrusion Modelling is essentially creating half of a shape and duplicating it to create the other half, it saves lots of time and is normally used when modelling something with a line of symmetry e.g cars or heads. This is the easiest way to model a photograph or drawing.
3D Development Software
3D modelling requires specialised software and there are many different kinds out there. Some are subscription based meaning you will have to pay a upfront, monthly or annual fee to use it and some are free to use.
Here's some 3D programs available now:
Maya - Maya is one of the most well known 3D modelling programs on the market. It is used for modelling, art, animation, simulation and rendering. The customer must pay either:
- £170 a month
- £1,370 a year
- £2,605 2 years
- £3,700 3 years
- Free for students
3D Studio Max - 3DS Max is used to create digital graphics, models, images, animations and games. It can also be used to create simulations by linking with different programs.
Prices:
- £170 a month
- £1,370 a year
- £2,605 2 years
- £3,700 3 years
Buy 3DS Max - http://www.autodesk.co.uk/products/3ds-max/subscribe
AutoCAD - AutoCAD is a specialised drafting software specifically designed to create blueprints for buildings, bridges, computer chips. This program is used in construction, architecture, engineering and manufacturing.
Prices:
- £180 a month
- £1,434 a year
- £3,870 3 years
Cinema 4D - Cinema 4D is used for 3D modelling, animation and rendering. It is capable of modelling, animating, lighting, editing textures.
As Cinema 4D offers many packages, prices can rang anywhere from £540 to £2,700.
Buy Cinema 4D - https://www.maxonshop.co.uk/?gclid=Cj0KEQjw1K2_BRC0s6jtgJzB-aMBEiQA-WzDMZNBf-2gEWbNpLF0TWlfYEoxBboNoBO_RGzmzz2J1A8aAhTL8P8HAQ
LightWave 3D - LightWave 3D is used for rendering 2D and 3D images both animated or static, animation and 3D modelling.
Prices range anywhere from $299 - $1395 (USD)
Buy LightWave 3D - https://www.lightwave3d.com/products/
3D Modelling File Formats
There are many file formats used for 3D modelling, all support different things like animation, images both high res and low res and compressed or non compressed.
Here are the relevant and important ones.
- .3ds - used by 3DS Max
- .dae - used for collaborative design
- .dxf - (drawing exchange format) used by AutoCAD
- .fbx - used to exchange files across multiple Autodesk programs
- .lwo - used for LightWave 3D
- .obj - supports most 3D modelling software
- .ply - stores 3D data from 3D scanners
- .skp - used for google sketchup
- .x3d - open source file format
- .mb - (Maya Binary) used for Maya
Constraints
While 3D modelling there are a lot of things to take into account, a big part of this is the constraints. There are multiple constraints the artist must keep their eye on.
Some of these are:
Polygon Count - Polygon Count (Also known as "Polycount") is the number of faces your object has, it's not always the more the better and in Games Design a low polycount would be ideal for a model.
File Size - File Size is very self explanatory, your files must be kept as small as possible! For example, if you were to create an iOS game for your iPhone that's 50GB it will not run under any circumstance because it's simply too big.
This is preventable in two ways.
Some of these are:
Polygon Count - Polygon Count (Also known as "Polycount") is the number of faces your object has, it's not always the more the better and in Games Design a low polycount would be ideal for a model.
File Size - File Size is very self explanatory, your files must be kept as small as possible! For example, if you were to create an iOS game for your iPhone that's 50GB it will not run under any circumstance because it's simply too big.
This is preventable in two ways.
- Create less detailed models for iPhone games as the player won't be able to see the finer details anyway.
- Find a way to compress your files.
Rendering - In animation rendering is putting everything you have created into one, every frame is essentially pieced together to run in real time for the viewer. Every video, film or animation has been rendered. It's the final step to finishing a piece of work.
Displaying 3D Polygon Animations
API - Application programming interface are sets of tools for creating software and applications. Two of these tools are Direct3D and OpenGL
Direct3D is used to render 3D images where performance is needed such as games, it links with the graphics card allowing for acceleration of the process.
OpenGL is used to render 2D and 3D vector images, the API links with the GPU to speed up the rendering process.
Graphics Pipeline
The graphics pipeline is essentially the rendering process.
The process consists of:
- Input-Assembler Stage - Supplies data to the pipeline
- Vertex-Shader Stage - Process vertices, a vertex shader takes a single input vertex and turns it into a single output vertex. Any transformations are also processed at this stage.
- Geometry-Shader Stage - Processes entire primitives.
- Stream-Output-Stage - Streams Primitive data from the pipeline to memory on its way to the rasterizer.
- Rasterizer Stage - Clips primitives, prepares primitives for the pixel shader and determines how to invoke pixel shaders.
- Pixel-Shader Stage - receives interpolated date for a primitive and generates per-pixel data such as colour.
- Output-Merger Stage - Combines various types of output data with contents of the render target to generate the final pipeline result.
Rendering Techinques
Rendering techniques are different ways to complete the rendering process. Different techniques usually use different algorithms to obtain the final image.
I'm going to talk about two different techniques called Radiosity and Ray Tracing.
Radiosity is a rendering technique primarily used for games, It is an algorithm that accounts for paths (represented by the code LD*E which leaves a light source and are reflected diffusely some before hitting the eye.
Rendering Engines
A Rendering engine is a program that renders marked up content and formatting information.
Here are two examples.
V-Ray is a plug in used in 3D computer software such as Maya 3ds Max, Cinema 4D and more. It can also be used in several industries like film, gaming and architecture. The plug in is a rendering engine that utilises global illumination algorithms such as path tracing, irradiance maps, photon mapping and directly computed global illumination.
Arnold is a ray tracing 3D rendering software that uses Monte Carlo rendering. It uses one level of diffuse inter-reflection so that light can bounce off of a wall or other subject and indirectly illuminate a subject. In some cases it uses the Open Shading Language to define the materials and textures.
The two components are quite different, V-Ray uses global illumination where as Arnold uses Monte Carlo, V-Ray supports multiple platforms where as Arnold primarily focuses on film. Different rendering engines are used for different products and in this case are similar to game engines.
Parallel Programming (Distribution)
Parallel Programming is a way of taking a problem and essentially breaking it down and then solving them at the same time, thus solving the larger problem at hand. This process makes the rendering time quicker.
Lighting
The rendering process must compile all components including lighting; textures; shadowing; vertex and pixel shaders. The process could be quick or take an extensive amount of time, that depends on the level of detail on all of these things.
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