MAA 1134: Principles of 3d Modeling Through critical analysis, the student will apply basic design principles to the solution of visual problems using elements of 3D design. The student will conceptualize 3D coordinate systems, construct 3D models, and perform mathematical computations as they apply to geometric construction.
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Modeling:
Models are created by the artist from a series of individual points (dots.... which are called verticies). These dots exist in 0 dimensions of space. They have no length, width, or height.
When a second vertex is added, we get an edge, which has 1 dimension (length)
When we add a thrid, we can make a face, which has 2 dimensions (length and height in this case)
When more faces are added, we can create a fully realized 3d object
The Polygon from The Guerrilla CG Project on Vimeo.
As an introduction to Maya and 3d modeling, this course is designed to teach us not only the parts of the Maya interface and the Maya workflow, but also the various types of geometry utlized by 3d modelers. Each of these types of geometry are created in 3d Cartesian Space, utliizing an X, Y and Z axis for plotting points and understanding space. X represents side to side, Y represents up and down, and Z represents foward and backward. (Maya of course can also represent a 4th dimension, time, as utilized for the creation of animation). Among those types of geometry used are:
UNDERSTANDING TYPES OF GEOMETRY: click the image below
The simplest to understand and manipulate in 3d, the polygon surface consists of (at it's simplest) a face or set of faces that are joined together. Each face has a specific ammount of edges. A Triangular face (or tri) has 3 edges, a quadrilateral face (or quad) has 4 edges, a multi-sided face of 5 and above (N-gon) has 5 or more edges. For the purposes of this class, we will want to model in all quad meshes when working with polygons for some reasons that we will discuss later on.
Each edge is represented as a line between two points known as Verticies (which is the plural of Vertex, a single point). The vertex is the single simplest component of a polygon object.
A polygon object can exist and be manipulated as a whole while in Object Mode (note how the grid lines are green),
or it can be manipulated at it's sub-object level, or Component Mode. Verticies, Edges, Faces and UVs are all example of object components (note how the lines turn blue and you can see dots for the indivdual faces in the Face component mode).
MODELING WITH POLYGONS: OPTIONS---CLICK ON IMAGE-->
UVs- are an additional component that coordinates 3d space with a 2d representation of that space onto a map (known as a UV map). Very simply, there will be a UV point wherever we find a vertex (at the intersection of multiple edges/at the corners of a face).Think of UVs like the city of San Francisco represtented on a Globe. There it is an identifiable place in 3d space and that is the Vertex. If there was a sudden Volcanic erruption underneath the city and it rose up off the globe due to the volcano underneath, we would have to manipulate the vertex since it has moved in 3d space. However the UV is like a representation of San Francisco on a map such as a Mercator or Robinson map. Even though the map is different between these two types, the city itself has not moved based on the way we draw the map. UV mapping will be discussed more in Materials and Lighting. The UVs define space differently from verticies in that that vertex points are manipulated in X,Y,and Z space (think of earth in terms of the larger galaxy), and UVs are manipulated in UV or local space (east-west and north-south).
A polygon object comprised of multiple faces will often look angluar unless smoothed. We can take an octogon, such as this stop sign and smooth it to produce a smoother shape by doubling the amount of faces:
The more faces we add to a model, the smoother it will get. But also, the more faces we add, the harder the model will be to animate (since we will have many more verticies to move), and the longer our file will take to render (since there are more points to calcuate positions of) and the larger the file will be to store (since there is more data).
A Non-Uniform Rational B-Spline. This type of geometry is inherently curvy based on the fact that a series of "Control Verticies" are used to handle tangency of a single curving line (known as an isoparm). NURBS based geometry can be created and controlled in ways similar to Photoshop or Illustrator's Pen Tool. One major difference between NURBS and Polygons is that the isoparm component of a NURBS object (which is mostly simialar to a polygon edge) is not bound between two points. In fact, an Isoparm will sweep from one side of a surface all the way to another (think of lines of lattitude or longitude on a globe). It is this chracteristic of an isoparm having more than 2 verticies that allows for a curve.
Since the NURBS surface does not need to be smoothed to created rounded geometry, it is perfect for creating curvilinear forms. Yet, its drawback comes from the fact that to create complicated organic meshes, we need multiple patches of NURBS surfaces that are stitched together, much like a quilt. This proccedure is oftern quite complicated to perfect.
Subdivisional Surfaces (SubDs)-
The SubD is a compromise between the ease of use for construction of a Polygon Surface, and the ability to easily control curves from a NURBS mesh. Built as a polygon surface (using all quads--- the Catmull-Clark scheme for subdivision that Maya uses will not accurately compute triangles or n-gons, another reason to use all quads in construction), the mesh can be converted into a SubD mesh. The advantage is that we can specify areas that need to be subdivided for additional detail or curvature. Disadvantages include drastically higher file sizes.
Unlike a program like Photoshop with uses Raster Graphics, 3d modeling programs use Vector Graphics, which is what allows us to zoom in and out (or arbitrarily define size) without pixelation. When we are done modeling or animating, we will Render out our scene. This is a process in which the computer's processor converts that data that until now has been visualized using only the video card, Vram and Ram, from a vector graphics image into a raster image such as a JPG or Tiff or BMP, etc....
Primitives from The Guerrilla CG Project on Vimeo.
For more information on the Basics of the Maya Interface, please take the time and watch fellow Autodesk Certified Instructor and AI of California, San Francisco Instructor: Aaron Ross's videos on the Maya interface at his website, the Digital Arts Guild. He does a wonderful job explaining in detail each of the concepts I have described above and in class, but in video form.
The 5 YouTube videos (also available as downloads) on his site are the perfect companion to our course introduction and help resolidify your foundations before moving into our Chair Project.
Here is a link to his website with the videos for Maya Basics:
We will be modeling a chair based on images from handouts from furniture magazines:
This chair was created only from Polygon cube primatives using the techniques deliniated below:
Click on the images below for links to Video Tutorials. This series covers creating a Chair from 3d Polygon Primatives in Maya. All images and videos are copyright Andrew Klein.
Part 1 of 5, this video from Andrew Klein (www.andrewklein.net) covers the creation of polygon primitives, adding components with the initial creation attributes, and editing component to create the base for the chair.
In Part 5 of 5, this video from Andrew Klein (www.andrewklein.net) covers how to create the back of the chair and the final grouping to complete the project.
- A GOOD TUTORIAL FOR LEARNING THE MAYA INTERFACE <--CLICK HERE
- MAYA MODELING WIKI
- SIMPLE POLYGON MODELING TUTORIALS
Viewport Bar Options:
Hotkeys/shortcuts:
MAIN TOOLS:
Q Selection Tool
W Move Tool
E Rotate Tool
R Scale Tool
T Manipulator Tool
Y Repeat Last Tool
G Repeat Last Action
F Focus on ObjectVIEW CONFIGURATIONS:
1 Angular View
2 Angular Cage + Smooth (subdivided) View
3 Smoothed Preview
4 Wireframe View
5 Smooth Shaded View
6 Textured View
7 Hardware Lit View
8 Paint Effects Canvas (not recommended using)
OPERATIONAL MODIFIERS:
S Sets an Animation Key on all channels
Shift+W Sets an Animation Key on Translate Channels only
Shift+E Sets an Animation Key on Rotation Channels only
Shift+R Sets an Animation Key on Scale Channels only
P Parent an Object (Shift-P to unparent)
X Snap to Grid
C Snap to Curve
V Snap to Point
Insert Toggles being able to move the pivot point
Ctrl-G Groups objects or creates a null group if nothing is selected
Ctrl-D Duplicates an object
Ctrl-Shirt-D Duplicates an object while performing a Special operation
Ctrl-Z Undoes the last action (up to 50 times by default)
Ctrl-S Saves the scene fileCAMERA TOOLS:
Alt+LMB Tumble Tool (rotates the camera)
Alt+MMB Track Tool (moves or strafes the camera side to side)
Alt+RMB Dolly Tool (moves the camera into or out of the scene)
Alt+LMB+MMB Dolly Tool (moves the camera into or out of the scene) <---same thing
Scroll Wheel Dolly Tool (moves the camera into or out of the scene) <---same thing!!!
Spacebar Jumps to alternate viewport configurationQUICK SELECTION BASED NAVIGATION:
Ctrl+F9 Convert Selection to Verticies
Ctrl+F10 Convert Selection to Edges
Ctrl+F11 Convert Selection to Faces
Ctrl+F12 Convert Selection to UVs
Up arrow Moves up the hierarchy
Down arrow Moves down the hierarchy
Left/Right arrow Moves side to side in the hierarchy
Critical Concepts :
Centering the pivot point-allows you to change the location for the point at which you move, scale, rotate, or duplicate to the center of the obejct
Freezing the transformations-allows you to reset all the channels in the channel box back to 0 without moving the object back to the origin and rescaling it to its original shape
Reseting the transfromations-allows you, once you have frozen the transformations, to automatically move the pivot point back to the center of the grid (the origin)
Deleting History-allows Maya to forget about all previous INPUTS into the piece of geometry.The Difference between an Maya Binary file (.mb) and a Maya ASCII file (.ma):
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