HA4 Task 4 - Mesh Construction

How are 3D models constructed? Describe and explain the different modelling techniques available to a 3D designer.

Remember that you are trying to comprehensively explain the theory and applications of 3D with elucidated examples and consistently using subject terminology correctly.

Mesh Construction

This is a technique that is used in 3-D modelling where the model is created by modifying primitive shapes to create a rough draft of the final model, in most cases. A primary function of box modeling involves extruding and scaling the faces, which are the flat planes that make up a model.
Source:http://i.imgur.com/HHhzcFZ.png

This is an image that I found on Google, and it is a good example of box modelling. It features a box, which then has the faces modified, and then modified even further to look like a foot. As you can see, it is made by modifying the faces of the model to turn something as simple as a box into something more that it was before.

Now there's different modeling techniques such as Extrusion Modeling, and Spline Modeling. These play a big part in creating meshes for video games. I will now go through both sections explaining them in more information.

Extrusion Modelling 

This is a common modelling method that is also sometimes referred to as inflation modeling. In this method of modeling, you could create a 2D shape which traces the outline of a photograph or a drawing. This would be done more commonly using the line tool, because of its simplicity and because it is so easy to work with and create things with it. You then use a second image of the subject from a different angle and extrudes the 2D shape into a 3D shape by following the shape’s outline again. This method is common for creating faces and heads in modeling, and artists will generally model half of the head and duplicate the vertices, invert their location relative to a plane and connect the two pieces to ensure that the model would then be symmetrical. This method is widely used by 3D artists because of it being so practical, quick and simple.

Source:http://blendermama.com/wp-content/uploads/2009/12/strip01-extruding.jpg
Source:http://3.bp.blogspot.com/-G_RQxa8XBcw/UhwXdSU2QPI/AAAAAAAABh0/iXWMJm9yNB8/s640/Extrusion-Modeling1.jpg

Spline Modelling

A spline is generally a special function that involves polynomials in the mathematics realm. The term spline may also be more familiar to people as it links to computer science. It is adapted from the shipbuilding term that describes the tools used by draftsmen and the ship builders to easily draw accurate shapes. This makes sense, as splines are the shapes that you could create on 3d software. Constructing a spline is simple, which makes it a popular choice of modeling when it comes to designing digital models, and their curve design helps to easily manipulate it. They can be used in one dimensional or multi-dimensional applications and can be used in various functions.

Source:http://www.allen3d.com/spline_alba5.jpg
Source:http://www.mikerusby.com/images/basehead1.jpg